BCM Community
Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Sean on July 18, 2009, 04:54:37 PM
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Folks,
Once again I throw myself upon the kindness of the vast resources here on the board.
Today, pulling the westbound grade out of Albuquerque, we apparently blew the turbocharger. What I seek from this group (unless one of y'all are heading past here and want to lend a hand) is some information about what else we may have damaged, and what it is going to take to repair. The engine in question is an 8V92TA, DDEC-II, 475 horsepower.
Description of problem
We were pulling perhaps a 4% grade at 60 mph in 95+ heat on I-40 west of Albuquerque, heading west. We had just passed the Route 66 casino at exit 140, and I was not noticing any problems until mid-grade, when things slowed down as per usual on the grades. I had one eye on the road, and one on the DDEC temperature reading, which had just climbed to 204 (recently normal for us on grades in the heat). Cruise was set on 62, and as we just slowed down below 50 I was just about to cancel it, when the CB came to life with a report that "boy, that bus is smoking." Sure enough, a ton of white smoke was billowing out the back.
A quick check of the gauges revealed everything normal except turbo boost pressure, which had dropped to zero. We immediately took the shoulder, where I made a quick call to friend and DD guru Virgil Cooley of PEDCO, to get his opinion on whether we could nurse it back to Albuquerque (30 miles), or if we had to stop immediately and get towed.
His opinion was that we did probably blow the turbo, and that we faced a decision: risk further damage to the engine by running it, or risk damage to the coach with a tow (Virgil is very familiar with our hard-to-tow rig). But he felt that as long as we had plenty of oil, and oil pressure stayed above 40 psi under load, we would probably be OK for a few miles.
We were not stopped in a safe place in any event, and so after the phone call we took a vote and decided we would nurse it along to the next exit (2.5 miles), make a U-turn, and then nurse it back another 7 miles to the casino, which is where we are now. We kept the coolant temperature below 190 and the oil pressure up at 40 the whole way, but the exhaust clearly got extremely hot (it melted through the trailer wiring harness), and we burned plenty of oil the whole way.
Current Status
We are well-parked in a truck stall at the Route 66 Casino Truck Plaza. There is still plenty of oil in the crankcase, although it looks like we lost maybe a gallon. There is oil underneath both airbox drains (usually, we have little to none there), There is also a pint or two under the muffler.
We've called our tow service, Coach Net. They called around to all the shops on their list in Albuquerque, but no one is open today. They will continue and get back to us on Monday. If we make the decision to get towed, say to Stewart & Stevenson, it will not cost us a dime -- we are fully covered. However, there is always the risk that the coach will be damaged towing it that far, and pulling the axles is dicey at best on this coach -- if they damage the seals, it could take months to get replacements.
Options
- We can have the coach towed to S&S or any other shop (recommendations welcome) and have the work done entirely there. That gives plenty of options should there be other problems besides the turbo, plus access to a warehouse full of parts, and presumably 2-stroke DD qualified mechanics.
- I can pull the hatch and try to get the turbo off myself tomorrow when everything has cooled down. I can then run the turbo into ABQ for exchange, or Virgil tells me PEDCO can overnight me one on Monday, and I am guessing I can talk the folks here at the casino into receiving it for me.
- There is a Freightliner dealer just eight miles east of here, on the north frontage road. We've already nursed her 9 miles or so, I would figure I could nurse it another 8 to get it there -- I'm certain they have at least some 15W-40 here at the truck plaza. Unknown until Monday morning whether they will even take us over there, but that's the closest shop.
Questions
- What damage did I do with the exhaust getting that hot? We do have exhaust blankets from the manifolds all the way to the muffler, including around the turbo. I am assuming the head temperature was within limits from the coolant temperature being normal.
- I am assuming that all the oil in both the airbox and the muffler is from the turbo. I am not an expert on turbo failure modes -- does this sound normal (well, insofar as any failure is "normal") for oil to be flowing out of both the intake and exhaust sides of the unit?
- Since oil is clearly dumping into the airbox, will I have to take the aftercooler out and clean it?
- I have a hatch directly above the turbo. What other access will I need to remove it? For example, will the DDEC ECM need to come out? If I have to come in from that direction for anything, I'm hosed, because I will need to remove some coolant cross-over lines, and I have no way here to capture the coolant if I do that.
- Alright, I know this one is open-ended: what would you do in my shoes? I can rewire this bus from front to back without any help, but engines are just not my depth.
History
In case it is important, I should tell you that this engine has 130,000 miles on it since new (1989). It has been in-framed twice in that time, both times due to dirt ingestion. Both in-frames included eight complete cylinder kits, rebuilt blower and rebuilt turbo (Garrett). The first in-frame also included eight injectors; the second time around, we only replaced a couple that looked to be bad. The last in-frame was perhaps 40,000 miles (two years) ago.
In March of this year, we stopped by PEDCO (who did both in-frames) to have them track down a handful of oil leaks. We had also been seeing high silicon levels (but no wear metals) in the two oil samples leading up to that visit, and, wary of dirt issues from two previous episodes, asked them to check the whole air induction system. We also pulled another sample, which came back with normal silicon levels -- we never did figure out where the Si was coming from. While we were there, I mentioned that, subjectively, I felt like I had diminished power and some extra black smoke, but no issues were found on that score.
Fast forward to June. I continue to have a nagging suspicion that we are suffering a power loss and excess smoke, but all DDEC readings are normal, as is fuel burn. As we climb into the mile-high zone of the intermountain west, I am noticing this more and more, and we are also running hotter than we think we should be. So we pulled into Stewart & Stevenson in Farmington, NM for a check-up. There we discovered a loose exhaust clamp upstream of the turbo, which could certainly account for all those symptoms: black smoke, low power, and higher temperatures, even though the boost pressure "seemed" to be in the normal range. That was less than 1,000 miles ago and we got a "clean" bill of health.
After a while, even with 100,000+ miles of experience driving this very coach, I start to doubt my own judgment about these sorts of things, and thus, despite a continuing nagging feeling that we were putting out more black smoke than normal and suffering from reduced power, we chalked it all up to high-altitude operation, right up until today.
So there you have it. We're stuck here on the Laguna Nation until Monday -- at least the casino has a pair of restaurants, and the truck plaza has a c-store. In the meantime, any and all feedback, comments, and suggestions are welcome. Please post them here, where it will all make Jim Shepherd feel a little less lonesome :)
-Sean
http://OurOdyssey.BlogSpot.com
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Can't offer any help other than moral support. Good Luck.
Don't stop doubting your gut feelings... You knew something was not right and the pros put you at ease. Not intentionally, of course. But you know your equipment better than anyone.
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Sean, I PM you a phone number good luck
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Sean, you did not need to do this to make me feel better :)
I would pull the cover and see what you can see. The white smoke and heavy use of oil probably suggest that it is the turbo. However, if you have a charge air cooler, I would check to make sure the short connector hoses have not blown off.
Like you, I am not an expert. However, if you can pull either the intake hose or the exhaust pipe off, you should be able to see what has happened to the turbo. If the hot side turbine has let loose, that would not be good and you should not drive it (obvious). If it is the bearing that has let go, then you could consider driving it if it only has a little slop in it, but you would risk the turbines getting into the housing.
My recommendation is to look at the turbo and if it has any damage, then pull it where you are and get it into Albuquerque.
Knowing Clifford, I am sure you have gotten good advice.
If I recall, there was some discussion on one of the boards a while back about how your oil system and drain back was plumbed. After you figure out what has happened, you probably want to talk to Virgil and make sure there is not something in the oil plumbing that has caused a very premature failure.
Wish I could be more help.
Jim
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Sean;
If you post your engine serial number or email me, I might have your cartridge on my shelf.
Along with the same info that Jim posted, I would try to pull your intake boot and inspect the compressor wheel. See if there is oil in the inlet. Check your compressor wheel. If it is rubbing your housing then your bearings are worn. Without removing the exhaust piping it would be tough to inspect the turbine wheel.
Goodluck
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If you post your engine serial number or email me, I might have your cartridge on my shelf.
My engine is serial number 08VF137462.
Along with the same info that Jim posted, I would try to pull your intake boot and inspect the compressor wheel. See if there is oil in the inlet. Check your compressor wheel. If it is rubbing your housing then your bearings are worn. Without removing the exhaust piping it would be tough to inspect the turbine wheel.
I got the hatch open tonight. In the morning I will remove the intake duct and see what I can see on the impeller. I will also take the exhaust wrap off and see how hard it will be to just remove the turbo. I am assuming that once I loosen the clamps and bolts right on the turbo, I can wiggle the exhaust pipe out of the way -- is that a bad assumption? Basically, I have to do all the work from directly above through a roughly 18" by 24" hatch.
If the impeller (compressor) has been rubbing the housing, will I need to remove the blower to inspect for damage and/or debris on the aftercooler?
-Sean
http://OurOdyssey.BlogSpot.com
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Sean,
I feel for ya man! (and Louise and the kids too!)
I wish I were closer or even able to offer any assistance at all, but I am unable to do so.
I agree with popping the hatch and checking the turbo. You can do it! On your engine the turbo is right up top & easy to get to. It's not that hard to take off or even put back on, but it isn't light either! Be sure not to twist, bend, kink, or break the oil feed line! If you don't have the correct tool (whatever it might be) get someone who does to assist!
As far as towing goes if and only if there is a stretch removable goose neck trailer available would I allow "Odyssey" to be "hauled" not towed!
You have too nice of a coach to let just any yengyang hook onto it and do who knows how much damage to it (unless it were an absolute emergency!), unless they provide GUARANTEED written proof that any and all damage caused by them will be repaired to your satisfaction immediately!
It might could be landolled if there are tall overpasses all the way to where you were taking it (which out there is possible!), but as tall as "Odyssey" is I would not want to chance it! (even at that, the approach angle of a Landoll would most likely dragging front and rear!)
I'd vote to fix it where you are either yourself or with help!
BTW I do have an identical engine here in the parts bus! (I know you don't need and engine, but I got one if you need me to check anything on it! mines in a German bus too!)
Sorry again to hear of the troubles! :( BK :(
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Sean,
You and I were posting at the same time!
If you take the clamps, oil feed & return lines and the 4 mounting bolts loose the turbo should be able to be lifted straight up off the blower! If you find pieces of the turbine missing then it's back to having it ntaken in for major inspection! But I really think since you were able to drive it as far as you were that it's gonna be as simple as replacing the turbo and go!
Call me if you need to talk to someone, I'm up!
:-\ BK :-\
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... Be sure not to twist, bend, kink, or break the oil feed line! If you don't have the correct tool (whatever it might be) get someone who does to assist!
Umm, OK, I'll bite: what special tools will I need? I have a full set of SAE and metric sockets and combination wrenches; does the oil line require some weird spanner to loosen?
As far as towing goes if and only if there is a stretch removable goose neck trailer available would I allow "Odyssey" to be "hauled" not towed! ... It might could be landolled if there are tall overpasses all the way to where you were taking it (which out there is possible!), but as tall as "Odyssey" is I would not want to chance it! (even at that, the approach angle of a Landoll would most likely dragging front and rear!)
Actually, as I just told Mark Renner over on the other board, I don't think we can get the coach onto a Landoll (or any other flatbed); even the long Landoll has too steep an angle-of-approach for us, and I think we'd get hung up front and/or rear trying to load. Not worried about the height out here -- all the overpasses are 15+. But I think the loading issues would mean that the only way to get towed is to use a 10' under-reach lift and wheel cradles, then pull the axles. This last item makes me nervous -- if they damage the seals, we might be sidelined for a long time.
Thanks for the offer of help; as I get into it tomorrow I may need it.
-Sean
http://OurOdyssey.BlogSpot.com
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Umm, OK, I'll bite: what special tools will I need? I have a full set of SAE and metric sockets and combination wrenches; does the oil line require some weird spanner to loosen?
No it shouldn't take any "special tools like a spanner or such, but some times line wrenches, and swivel or wobble sockets are necessary to get thing loose in tight areas!
Actually, as I just told Mark Renner over on the other board, I don't think we can get the coach onto a Landoll (or any other flatbed); even the long Landoll has too steep an angle-of-approach for us, and I think we'd get hung up front and/or rear trying to load. Not worried about the height out here -- all the overpasses are 15+. But I think the loading issues would mean that the only way to get towed is to use a 10' under-reach lift and wheel cradles, then pull the axles. This last item makes me nervous -- if they damage the seals, we might be sidelined for a long time.
Thanks for the offer of help; as I get into it tomorrow I may need it.
-Sean
http://OurOdyssey.BlogSpot.com
My point exactly (I used to operate both heavy duty tow trucks and landolls!) , A GOOD operator could run you coach up on blocks and then load it on either a Landoll or a stretch RGN while constantly moving cribbing. And a good operator could also tow it with an undereach and cradles as you point out. But again he's gonna have to run the steers up on blocks in order to clear the low body and then be very careful not to bind it in dips and drives while not bottoming it out in the rear also!
It can be done, but I'd rather not chance it, if it were me!
I also now what ya mean about the Mercedes axle seals (Setra uses the same ZF rear end)
Anyway I'll be here in the shop pulling an engine out of a bus all day tomorrow, so if ya need me I'll be here! Two 7 zero-seven zero 5-eleven thirty nine ;D BK ;D
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So, just thinking out loud here...
If we do decide on an under-reach tow, can I leave the axles in if I disconnect the driveline at the pumpkin? I know for sure the tranny can't be spun from the tailshaft while being towed, but is there any problem with the axles, spiders, and the rest of the diff spinning around for 25 miles?
Another quick question on removing the turbo: I've been studying photos of the turbo both installed and on the bench. I think I know how to disconnect it from the intake, blower, manifold Y, and exhaust. Then it looks to be held down with two bolts, one on either side of the oil supply line.
Do I disconnect the supply line from this plate, or just undo the bolts? And where does the other end of that supply line come from -- I can't make it out. Does it come off the blower someplace? I assume I have to loosen or disconnect that end, and I think I will be working blind -- it disappears behind the ECM somewhere.
Also, if I loosen the clamps at the output side of the impeller plumbing, will I be able to work the whole thing loose, or will I need to remove the four bolts and pull the metal housing, which connects the impeller output to the blower, out with the turbo?
Thanks for all the help.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean,
Yes you can leave the axles in and remove the drive shaft (if you can get to it! It's very heavy, hard to get to and there are like 10 bolts on each flange!) I have done this before on units that had the axles frozen up and would not come out for anything! Be sure to take it all the way out and not just off one end and then tie it up! I have seen it drop down in tow ruining the trans, rear end, driveshaft and much other damage that's just not worth the chance!
As for the turbo, I'll have to take a wa lk down by the shop and refresh my own memory!
;D BK ;D
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Rather than take the flange off, can you undo the U-joint? Cap is usually held on with two bolts. When I just took mine off, the cap was pretty "stuck" in the bore. I had to get a BIG wrench to turn it in the bore (cap has flats on it) and it finally came out.
The other issue with the turbo is that the mounting nuts/bolts can be hard to get off. Your turbo has not been on long enough to have all of the heat damage to the threads, but I would still spray them with a GOOD penetrating oil. The truck shop should carry PB Blaster and I would spray the bolts at least an hour ahead of time. If any of them feel stuck after you get them to rotate a turn or two, keep going back in the tightening direction and spray some more fluid on.
I can't remember if they are bolts or studs. If they are bolts, not a big deal to break them. If they are studs, work very hard not to break them, as it will be a big deal to drill them out.
Concerning the drain tube. It is very think wall tubing and the chances are you will damage it getting it off. Not a problem. That is basically a consumable, and they will have the part at the dealer.
Update: I just went over to BNO and I see that you are getting about the same advice over there. As soon as you get one or both sides of the turbo exposed, let us know what you find. I would pull the cold side hose first (easiest) and see if the bearings are toast. Also, since your turbo is top mounted, it sounds like you do not have a drain tube to contend with.
Jim
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I am sorry about this ordeal and hope everything goes the least costs ways for you.
One of the steps that can be not over look…is the oil drain tube as well the feed tube. Make sure it is not restricted or plugged so that it can keep the seals from over heated to cause it to leaks.
And have the engine oil checks for engine’s bearing (include cam bearing) wear to cause lower oil circulation flowing to the turbo. Even the pressure gauge can fool anyone if it taps off in between bearing. This may not the case with 8V 2-stroke.
The bottom-line inspects anything that can cause the seals to cook or whatever to leaks.
BTW…about inline wrench is also called “flare-wrench”…it a 6-side wrench with an open end to allow the tubing to cleared. A good flare-wrench to avoid mushrooming the fitting.
Wish you well.
Sojourn for Christ, Gerald
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Sean, the oil supply comes from the lower right side of the engine most of the time you can remove the line from there and remove the turbo.
If I were you I would remove the blankets and check for wetness around the exhaust flanges feeding the turbo on both sides if one side is wet don't waste your time removing the turbo because it is going to be a lot deeper.
If both sides are dry then you have a turbo problem good luck
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OK I just got back from the shop where I checked both our 8V92TA DDEC units ('89 & '91 Setra's) and heres the skinny!
You only have the oil feed line coming in the top of the turbo from down around the alternator area (at least on both ours is does). But I feel confident that with plenty of penetrating oil and care you'll be able to take it loose at the turbo and set it aside.
Then you have the air intake hose coming in (big rubber hose from the air cleaner) to one side of the turbo. On the other side you have the exhaust flange with the 4 bolts. These maybe difficult to get out! I'd soak, soak and re-soak these with penetrating oil and probably re-soak them again!
Then you have a short hose going to the blower housing from the turbo (easy to undo), and last the 2 BOLTS mounting the turbo itself. (one on each side of the oil feed line.
On these engines there is not an oil return line as the oil exits the turbo housing down into the blower housing at the mounting flange.
Again I still feel it is your best bet to tackle this rather than risk damage to "Odyssey" by towing it!
Call if you need verbal or moral support! ;D BK ;D
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Sean, for what it's worth, I did the same thing two months ago halfway up the Baker grade. The bearings failed in my turbo. All I did was took the inlet and outlet sides off, removed the inlet wheel and pulled the shaft (with outlet wheel still mounted to it), stuck a bolt long into the shaft hole to clog it with a nut to keep it in place, put the intake and exhaust pipes back on and drove it 400 miles home without incident (and without a lot of power, and a lot of smoke going up grades!!
I also plugged the oil line to it. Maybe doing something like that is cheaper and more practical than a tow... I can't imagine it'd hurt your exhaust- steel pipe takes much more heat than your engine will put to it. I did ruin my EGT sensor and toasted the turbo drain and the wastegate hoses, but that was all.
My inlet wheel had a left hand thread. All it took was holding the outlet wheel with pliers and unscrewing the inlet wheel, and it all popped off. Don't know how your turbo is constructed but probably similar. Mine's a garretson. Note that I'm talking about my Crown, so your situation may vary....
Being it seems you havn't shattered anything and your engine is not full of little turbo bits, this oughta work just fine for you...
Good luck
gary
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Sean
Charlie and Detroit Diesel are now very close to where you are
They moved to the west side of the river
If there is anything I can do to help let me know
Melbo
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Sean, Here are some pictures of my 8V92TA sitting in the shop...showing the turbo and which bolts and nuts need to be removed, all you need is 1/2, 9/16, 5/8ths wrenches.....nothing special there are only 8 bolts and clamps to be removed! Good luck! First photo is the clamp from the turbo hot side 1/2 wrench or socket!
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2nd photo is the clamps and boot on the turbo discharge again 1/2 wrench or socket.
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3rd photo are the two 5/8" bolts that hold the turbo down, and the 5/8" nut for the oil line,
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the 4th and last photo is the T on the outlet lines to the turbo, there are 4 9/16" nuts, this should be everything you need to remove the turbo. Also the clamp on the cold side needs to be removed also. Good luck!
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Well Pat beat to it I went and took pics too!
If ya can't get the 4 flange nuts off the studs, then you might could remove the 2 clamps holding the T to the pipes coming up from the exhaust manifolds! As shown in this photo.
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Here is the oil feed line and one of 2 mounting bolts visible.
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Even when the nuts look bad on the exhaust flange if they are original DD nuts they come off easy it's when someone replaced nuts with ones from Ace Hardware that gives you the problems. FWIW I pay the $2.20 each for those 4 nuts for peace of mind knowing they can be removed when the time comes
good luck
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Update:
Sometimes, it's better to be lucky than good.
I had just wrestled the exhaust blankets off the turbo (showing evidence of gas leakage -- soot -- around the inside edge, as well as a spot of fresh oil), had soaked the exhaust flange studs in WD-40, and was loosening the intake duct to check the impeller, when Louise, on her way to the laundromat here, spotted a "mobile mechanic" truck in the parking lot.
We called the number, and Jim the mobile truck repair guy agreed to come over and have a look. I took it as a good sign that, when I told him it was an 8V92, he said "oh, you must be in a bus." Since he was already here, he agreed to work for just his hourly rate of $75, without the mileage charge. Pretty, good, I thought, for a Sunday morning.
Jim had two things that I did not:
- 30+ years of experience working on diesels full-time as a mechanic.
- A whizzy cordless 1/2" impact wrench.
We chatted for a few moments, and he picked up basically right where I left off. The good news was that the impeller looked to be in good shape; so much so that, at first, Jim thought the turbo was fine (for just a heart-stopping moment). A few seconds later, though, he realized he could wiggle the impeller in the housing, and he predicted that the shaft was broken in two. Whew... that meant it was very likely a bad turbo and nothing else.
He had the turbo out in less than half an hour. I figured it would have taken me two hours to do the same work, between going very slowly and methodically because I've not done it before, and having to work the bolts loose in cramped quarters with just hand tools. As it was, two of the exhaust flange studs came clean out, nut and all (the nuts came off the other two as normal).
Sure enough, he was spot-on about the problem. The turbine/impeller shaft was broken in two, and the exhaust turbine was seized in the housing. This accounts for all the symptoms: high exhaust back-pressure preventing the blower from completely clearing the cylinders, unburned fuel likely continuing to burn inside the exhaust system, and oil flowing past the bearings and into both the intake and exhaust systems.
Careful inspection of the impeller (compressor wheel) showed no significant damage, and so we agreed that it was unlikely any debris was sent into the blower. He was willing to hunt around to find a turbo today, but we also agreed that I would have to pay a considerable premium to get one on a Sunday.
Later today I will get all the numbers I can find off the turbo (it's outside now, and just too bloody hot here in the sun -- I'll do it after sundown), and tomorrow morning I will start calling around. Recommendations for suppliers are welcome; also, if anybody knows exactly what turbo I need, let me know. I can load the turbo on my scooter and run it into Albuquerque for an exchange. I'll also need the exhaust flange gasket, oil return gasket, and blower adapter gasket (we could not get the turbo off the hose that leads to the blower without removing the adapter).
I'm pretty sure I can get this back in on my own, but I may well call Jim back, just to have a higher confidence that it's been done right. We were very fortunate to luck into someone with plenty of DD 2-stroke experience. In addition to his rate, the round trip mileage charge will be an additional $60. At least he is willing to come back and put in parts that I supply -- if he acquired them, there would be a 30% mark-up.
So that's the status. I'd like to thank everyone who has provided information or offered assistance so far. At this point, I think all I need is a source for a rebuilt turbo and the gaskets, preferably at something less than DD-distributor prices (I would be willing to bet Stewart & Stevenson can get me everything I need, for top-dollar prices).
In the meantime, we'll be sitting here in the air conditioning, courtesy of Dr. Kubota, and surfing the Internet.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean call Don Fairchild @ six six one-3 nine 1-45 twenty! He is a distributor and can overnight you one! I don't know his prices but he's reasonable and can tell you exactly which one you need from the #'s off the turbo tag or the engine serial # you give him.
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Sean, some Cat and Cummins engines use the same turbo model TV 8513 with a 1.39 a/r also you can buy a new Borg/Warner for less cash if you need a new one they are about 800 bucks without the hot housing depending on the store.
I am glad you didn't lose a injector tip. good luck
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Sean, the turbo number on mine is a Garret E8927027. Other info is VBM0104, 9032M24,
A/R .81.
Mine is NOT a DDEC. It is 525hp.
Changing a turbo is not very difficult. Good Luck.
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Sean;
The Garrett part number for your turbocharger is 465745-0001 >TV8513 family. Clifford posted the turbine A/R which should be 1.39, please verify. Joe posted the compressor housing A/R and number > .81A/R
The complete center section that you should be looking for "new" is a 442032-0022 I'm pretty sure that I have one.. I strongly recommend not getting a rebuilt unit but spending the extra $$$ and buying a new center section. This will get you a brand new bearing housing, backplate, compressor wheel and turbine wheel all assembled and balanced.
Make sure you inspect the turbine housing for cracks. If you have a crack that is running into the throat of the turbine housing, this will change the picture of things.
I'll post the Garrett build sheet for you shortly.
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Sean, the turbo number on mine is a Garret E8927027. Other info is VBM0104, 9032M24,
A/R .81. ...
and
The Garrett part number for your turbocharger is 465745-0001 >TV8513 family. Clifford posted the turbine A/R which should be 1.39, please verify. Joe posted the compressor housing A/R and number > .81A/R
OK, all the markings I see from the photos I have of this thing before it went in are as follows:
Turbine (exhaust) Side:
Garrett
171/89
3109 6 (on exhaust flange)
Impeller (intake compressor) side:
Garrett
A/R .81 M24
I do not see the A/R for the turbine.
Photos linked at the end of this post.
The complete center section that you should be looking for "new" is a 442032-0022 I'm pretty sure that I have one.. I strongly recommend not getting a rebuilt unit but spending the extra $$$ and buying a new center section. This will get you a brand new bearing housing, backplate, compressor wheel and turbine wheel all assembled and balanced.
OK. Three concerns: First, what does it take to replace the center section? Second, how quickly could I get one of these here in ABQ? Lastly, there clearly has been exhaust gas escaping around the turbine housing on the bearing side. Does that change your opinion about reusing the housing?
Photos:
http://odyssey.smugmug.com/gallery/131040_g58Tf#595657459_fxPCa (http://odyssey.smugmug.com/gallery/131040_g58Tf#595657459_fxPCa)
http://odyssey.smugmug.com/gallery/131040_g58Tf#595656689_eKZqh (http://odyssey.smugmug.com/gallery/131040_g58Tf#595656689_eKZqh)
(choose "Original" to see full-size)
-Sean
http://OurOdyssey.BlogSpot.com
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Sean,
An ancient Chinese CURSE is "may you live in interesting times". God only knows what some Chinaman "thinks" you did to him. :o
Good luck with this. I am greatly encouraged by the assist that the board has given you. Nothing short of wonderful. You should be on your way in a couple days max.
Would upgrading your turbo "size" give you more power? Is there any potential upgrade that you could take advantage of in this situation?
Cheers,
John
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Would upgrading your turbo "size" give you more power? Is there any potential upgrade that you could take advantage of in this situation?
Not really. Making any kind of change like that would require a new computer program (in the $thousands) and possibly different injectors. If there had been any easy way to do that, we would have done so during the in-frame.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean with the ease of FedEx anything can be shipped to you "next day"
To seperate the turbine housing AND compressor housing you need to mark/clock the two housings. The Rookie mistake for most folks is undoing the band clamps>you then struggle getting everything clocked when mounting the new components. Take a punch and mark the vertical 12 o'clock in relation to oil inlet fitting which is on top of the bearing housing. We want to call that the 12 o'clock reference.
Step two is to undo the band clamp on the turbine side of the turbocharger. You have mentioned the exhaust blow-bye. It can be caused by a loose clamp or a over tightened clamp> or lastly a erroded sealing surface >>either the bearing housing/center section or turbine housing. I would spray some penetrant to ease the removal of the housing. Grab a brass hammer and tap the housing arount the perimeter (not in one spot) Some HARDwood with a hammer will work. We want to keep the compressor on so that you don't destroy the compressor wheel > yes the turbine wheel is toast. With stubborn housings one will have to get the heat out and apply to the turbine housing. But since the housings were off a few years ago, you should get it off. Again I hold the compressor housing in one hand, and "beat" the turbine housing in a rotational motion. THIS is the hardest thing that you will have to do..
Next you will need to undo the clamp on the compressor housing. The housing will come off with gentle tapping.
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(http://i275.photobucket.com/albums/jj302/turboflat6/GarrettTV8513.jpg)
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Sean, I post the complete parts list for your turbocharger. You can order any part for your turbo at any Garrett turbo dealer. If you can read the info off your data tag (located on your bearing housing) we can then confirm what you have. That A/R for your turbine housing will be stamped inside the turbine housing inlet. FYI the 400HP engine uses a 1.23 A/R turbine housing. Everything else is the same.
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Kevin,
Thanks for the very complete description of the fix, as well as the parts list. I have to confess, I am nervous about tackling this -- I know the tolerances are very precise, and these things spin horrendously fast with incredible forces involved. Of course, someone with the handle "zero clearance" probably thinks these heavy-duty Garretts are "sloppy" :)
Sean with the ease of FedEx anything can be shipped to you "next day"
Sure... I had been thinking about getting a whole turbo -- this sucker must weigh 40 lbs, and I'd rather not contemplate what that costs to ship next-day. But, of course, the turbine/impeller assembly must be much, much lighter -- I'm guessing maybe four or five pounds?
I will definitely consider putting a new set into my existing housing. Although I might try to find a local specialist to do that for me; again, contemplating doing this myself gives me some pause.
Thanks again for all the help.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean, with your turbine wheel destroyed, you don't have anything to worry about. You can undo the clamp and beat the housing off. The compressor housing will come off with very little issues. All in all you have a destroyed center section. These are simple turbochargers vs the newest variable vaned units that are being used right now.
If you were up in Sumner, I would have that turbo in pieces in 30 minutes.. I would recommend that you hot tank the turbine housing and blast it>>aluminum oxide. I gather from looking at your 2005 pictures that your turbine housing is in decent shape.
With this all said, you really do need to find out what caused this failure. If you can get the turbine housing off, it will show you and "us" what the turbine wheel blades look like. These turbochargers do NOT break shafts on there own> typically this type of failures is induced by something else>> FOD impact on the turbine side or oil starvation. I guess that's one of the reasons why I'm asking you to get the turbine housing off. If you have rolled over or missing blades you have "deeper issues" Clifford has eluded to this.. I want to rule out further damage. On the other board I seen your reply about the bearings and the previous turbo rebuild. The bottom line is>>a faulty part or poor tolerance will have manifested itself sooner vs 4 years and "X" miles down later.
Sean, you have my email address, email me if you need help. Give me a call if need be.
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Here you go Sean I spoke with Cole and this where Stewart and Stevenson buys some of their parts an have some rebuilds done
Central Motive Power
3740 Princeton Dr NE |
1-800-782-2525
505-884-2525
If you need a bussines name to buy from the outfit which he doesn't think so but if you do Ed and Jim will help Jim owns a business there good luck
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Sean, I bought parts for mine off the net. I can not find the slip, sorry. But the guy knows his turbos and he had the parts in stock. Sorry not much help. Tom Y
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Unlike most of the others that are giving advice, I do not have any skills or experience with this. I sense that you might not have much either. Contemplating the consequences of a small mistake would make me look for either a new turbo or, at the very least, someone skilled to rebuild yours even if you supply all the parts.
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... If you can read the info off your data tag (located on your bearing housing) we can then confirm what you have.
OK, I found the plate. Hard to read, because it looks to have been spray-painted silver along with the rest of the unit when it was rebuilt, but it turns out to be a Detroit-Allison plate (I could barely make that out on the embossing) with the following two numbers stamped into it:
23503264
SK0127 L
That A/R for your turbine housing will be stamped inside the turbine housing inlet. FYI the 400HP engine uses a 1.23 A/R turbine housing. Everything else is the same.
OK, I found the Turbine A/R embossed on the other side of the housing. It is, indeed, a 1.39. Other markings on this side are "M1" and "G."
Do those numbers on the plate map to something from Garrett?
... If you were up in Sumner, I would have that turbo in pieces in 30 minutes.. I would recommend that you hot tank the turbine housing and blast it>>aluminum oxide. I gather from looking at your 2005 pictures that your turbine housing is in decent shape.
Well, shoot -- we were just in Sumner a month ago. Too bad the thing didn't break back then, but then again, that's par for the course.
I don't have any way to hot tank or bead blast the housing -- we're parked at a casino, and I don't have any equipment of that kind. So this would definitely be a factor pushing me to find someone here who can do it for me.
With this all said, you really do need to find out what caused this failure. If you can get the turbine housing off, it will show you and "us" what the turbine wheel blades look like. These turbochargers do NOT break shafts on there own> typically this type of failures is induced by something else>> FOD impact on the turbine side or oil starvation. I guess that's one of the reasons why I'm asking you to get the turbine housing off. If you have rolled over or missing blades you have "deeper issues" Clifford has eluded to this.. I want to rule out further damage. On the other board I seen your reply about the bearings and the previous turbo rebuild. The bottom line is>>a faulty part or poor tolerance will have manifested itself sooner vs 4 years and "X" miles down later.
OK, just to be clear, I don't know what the history of this turbo is before I got it. That was back in 2005 during my first in-frame; since then it has had ~70,000 miles put on it. It's also passed a bunch of dirt -- the engine got in-framed a second time, but my recollection is that the turbo was inspected, cleaned, and re-used. Since the markings are all identical to the 2005 photos I posted, I am certain this is at least the same housing; I will have to dig up the invoice to see if the turbo got rebuilt in 2007 (40,000 miles ago).
Help me visualize, here: what kind of things could cause FOD on the turbine? Presumably, anything hitting the turbine would have to first pass through the exhaust valves -- wouldn't there then be symptoms of other problems, too?
Sean, you have my email address, email me if you need help. Give me a call if need be.
Thanks for the offer; I may need to take you up on it.
-Sean
http://OurOdyssey.BlogSpot.com
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(http://i275.photobucket.com/albums/jj302/turboflat6/Garrettinterchange.jpg)
Sean, this shows the factory Detroit cross to the Garrett part number. Garrett is the OEM for the Detroit.
Thanks for posting the part number from your tag, it confirms all the parts given up above.
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Sean,
The number for the hot side is on the other side of the hh. and stamped on the inside of the flange. I cant tell from the pick but you have probably a TV8511 with a 1.39 HH. You can change to a 1.23 HH with out any program changes. It will help your mid range and low end
If you need help with a turbo let me know, I can have it ups overnight to you.
Royaleagle; your turbo is a TV8511 the E is a R for reliabuilt. Zero the # you gave is a TV 8513 you can't change the HH on yours.
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Another update:
First off, many, many thanks to all the folks who have come forward with advice, support, information, and outright offers of assistance, and especially Kevin ("zeroclearance") who is a turbocharger expert by trade and spent hours on the phone with me today talking me through various things.
I spent most of the morning on the phone trying to locate either a complete remanufactured turbo, or a new "cartridge" (entire center section, including turbine wheel, compressor wheel, shaft, bearings and bearing housing, and compressor backing plate, all factory assembled and balanced). We nailed down a Reliabilt remanufactured unit early in the day, but it was in Denver, and, at ~65lbs, I was looking at a good deal of freight to get it here overnight.
In the meantime, Kevin made some rather convincing arguments in favor of disassembling the one I have and putting a new factory cartridge in. For one, all the parts would be factory new and factory balanced, as opposed to a re-man where most of the parts are of unknown history and possibly only cursory inspection. For another, removing the turbine housing would possibly reveal more information about the cause of the failure.
While Kevin (and others) were working on tracking down a cartridge, I made arrangements with local bus nut Eddie, a contact generously provided courtesy of Clifford ("luvrbus"), to come over to his place north of town and use his parts cleaner and bead-blaster to prep our existing housings. I then set to tearing the turbine side apart.
Notwithstanding having heard from several people that getting the turbine housing off would be the biggest challenge, possibly requiring a torch and a hammer (and so I had prepared by hauling out my propane torch and 2-lb deadblow), the thing fell apart in my hands as I undid the clamp. That might explain the signs of exhaust blow-by we had seen aroung the clamp area.
The turbine wheel was extensively damaged, and, of course, we were looking for tell-tale signs of Foreign Object Debris (FOD) damage, which would indicate that bits of rings, or maybe even valves, were spitting out of the engine and caused the failure. While the wheel damage was not inconsistent with FOD, there was no matching damage in the throat of the housing, and the bent vanes on the turbine might easily have come from impacting the housing after the shaft let go. The only way to tell for sure is to pull the heads off, or put a new turbo on and start 'er up. Another turbo will actually be less money than pulling the heads, so we have our fingers crossed that it is not FOD, and we're just going to slap a turbo on.
In the process of diagnosing all this, we put up a photo album showing the old turbo just before, and just after removing the turbine housing, including turbine wheel photos, here:
http://picasaweb.google.com/louise.hornor/July202009TurboInterior#
After nailing down plans to do the cleaning and bead-blasting, and almost past the deadline for ordering the Reliabilt today, I got a follow-up call from Kevin, who had discovered that completely new, factory balanced cartridges for this model are discontinued and no longer available. I could have a Garrett OEM cartridge that was "partially remanufactured," or an aftermarket part of unknown alloy quality from Rotomaster, or a cartridge assembled by some guy in the Midwest out of new Garrett parts, all for the same price, around $800 or so delivered, with no warranty.
If I went that route, I would also still be faced with a couple hours work cleaning and media blasting the housings, and then I would have to assemble the whole thing correctly when I was done. At this point, the Reliabilt, which came with a 12-month warranty and would cost me about $991 plus tax, after core, started to look like the better option.
We ended up ordering the Reliabilt from Stewart & Stevenson, but, instead of having it sent next-day UPS for $225, we are having it sent by bus. If the Denver office got it in time, it should be at the Albuquerque office tomorrow, and shipping should be less than $80.
With any luck, I will be able to pick this up at S&S tomorrow morning, and have it back in the bus by the end of the day. Worst case, we should have it sometime Wednesday. I will carefully check oil supply and return lines for obstructions, and pre-lube the unit with STP before installing it. Kevin has given me some explicit directions for breaking the unit in, which will keep us right here for several hours after installation.
I will post another update when the repair is complete and we know whether or not it is the final solution of this problem.
And now, if you'll excuse me, I hear the siren song of the casino buffet...
-Sean
http://OurOdyssey.BlogSpot.com
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The number for the hot side is on the other side of the hh. and stamped on the inside of the flange. I cant tell from the pick but you have probably a TV8511 with a 1.39 HH. You can change to a 1.23 HH with out any program changes. It will help your mid range and low end
Don, your post came in while I was typing.
I posted the Detroit part # earlier, and, as Kevin's chart above shows, it crosses to the Garrett TV8513. That's also the number both S&S and PEDCO came up with when I provided the number from the DDA plate.
The A/R of 1.39 was, indeed, embossed on the "inside" of the turbine housing.
Thanks for your help.
-Sean
http://OurOdyssey.BlogSpot.com
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From recent experience I know how hard it is to remember to keep this forum updated when you are in the middle of dealing with a crisis. Sean, you are doing a much MUCH better job than I did under similar circumstances. Thank you from all of us who eagerly await each day's chapter in the ongoing story.
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Sean,
Looking at the photo album of the turbo disassembly it looks like an oil starvation meltdown doesn't it?
BK, Don or Kevin what does that damage to the turbine vanes look like FOD or overheating/oil starvation to you guys?
I leave it to the experts.
Sean, we're pulling for you. Hope this nightmare ends soon without too much money being spent.
I am not a gambling man but I might give one good pull of a slot machine to see if my luck was changing.
Just kidding.
Good luck,
Rick
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Sean, it was a pleasure talking to you today.. Like I told you, I had to "pay it forward" for all the good advice you have given over the years.
Hopefully you will be installing a turbo tomorrow and breaking it in..
Rick, there is a picture in the gallery that Sean has posted that show the turbine shaft inside of the bearing housing. It looks good and not discolored (blue/black) from "lack of lubrication" The turbine wheel did NOT seize. The shaft freely turns in the bore. FOD damage will typically knock off the blade tips. One or two blades really take the impact, and the next blade tips are less severe. It doesn't take much to impact a blade when it is turning 60K RPM plus. If you guys are interested I can post a few good pictures. Like I told Sean, this failure was a chicken or the egg situation. I'm leaning towards FOD from when he had the exhaust clamp fixed. A turbocharger will quickly fail when it has eroded blade tips. It runs in a "unbalance" state, which will destroy itself. When the head broke loose, it had the full energy of the exhaust turning it. Imagine your brake rotors with no pad material left>metal on metal...
For what has happened over the weekend with Sean, I think it will end well..
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Rick,
don't make me lie! I ain't no turbo expert! I just know when they work they work, n went they don't they are a pain!
Honestly it's hard to tell!
Sean,
Hey after looking at the pics I could've sent ya an identical one! It's in the bay of parts under the parts bus! Looks IDENTICAL! ;D
;D BK ;D
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Take a look at this photo it is number 4 from Sean's site. The nut appears to have lost its point at the 6 o'clock position. Also the round flat just below the nut appears to have lost a small chip. Could this be a point of origin for original failure? Or simply damage after failure?
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Take a look at this photo it is number 4 from Sean's site. The nut appears to have lost its point at the 6 o'clock position. Also the round flat just below the nut appears to have lost a small chip. Could this be a point of origin for original failure? Or simply damage after failure?
I think neither.
I believe what you are seeing is a small flat machined into the hub, probably after the cartridge was assembled, to dynamically balance the turbine. You can see the same flat in the photo I posted earlier:
http://odyssey.smugmug.com/gallery/131040_g58Tf#595657459_fxPCa
which was taken before the unit was installed back in 2005. The flat in that photo is at about the 11 o'clock position.
There is a similar machined spot on the compressor side.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean,
I went back and looked at the pictures of your bus. She's a beauty.
Rick
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... She's a beauty.
Why would I lie? But don't fall in love...
:)
-Sean
http://OurOdyssey.BlogSpot.com
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Sean, the flat being referred to is a spot that is ground in the balancing process. Some re builders weld to add weight and that can contribute to the friction weld that attaches the shaft to the exhaust wheel failing! The shaft and exhaust wheel are of vastly different materials. The exhaust wheel is from hastelloy to inconel and other materials all being high heat resistant stainless alloys! By the way the nut being referred to is not a nut at all! And I am not an expert but a person that once had a shop repairing industrial turbos. My definition of a expert is a drip under pressure or someone thousands of miles away from the problem saying pushing the reset button should have fixed the problem! Hope the best for You and hope You are on the road soon. Regards ,john
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Sean,
Only a musician would catch that!! I worked with those guys in the 80's. Lost a lot of brain cells.
Come to think of it... that explains an awful lot!
Fantastic Delusion was one of my favorites of theirs.
Trust me, they were "white punks on dope"
Good luck with your motor,
Rick
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Are we referencing the Tubes?
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Yes, Niles. Sorry, it was the first thing that popped into my mind when I read Rick's post. Which says a lot about me, I guess.
Rick, I'm sorry, but I am not a musician, only a music fan. Although my first wife was a bona fide roadie (stage hand), and had many stories to tell about the business. My current wife tells me I should sing Solo Tenor -- so low no one can hear me, ten or eleven miles away.
For anyone who's lost, the reference is to "She's a Beauty" by The Tubes. About, ahem, a peep-show girl, sung from the point of view of a hawker.
Update on the turbo situation shortly.
-Sean
http://OurOdyssey.BlogSpot.com
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Saw one of their first live shows @ Sawdust Festival, Laguna Beach, circa 1974???
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OK, here's where we stand now on the turbo situation:
The executive summary is that it appears to be completely fixed, and it also appears that it was nothing more than what we originally suspected, a blown turbo.
For all you die-hards, the longer version is as follows. As I wrote here yesterday, we decided to order a Reliabilt reman from Stewart & Stevenson, and it came down from their Denver location overnight by bus. I called the Albuquerque office around 11 this morning, figuring I should have already heard something from them, and they informed me that it had just arrived.
We loaded the old turbo on the back seat of my scooter and headed the ~20 miles back to town, avoiding the freeway by staying on old Route 66. Sure enough, S&S had the turbo, and it was the correct item. Unfortunately, the gaskets never arrived. No matter, since checking the order revealed they had ordered the wrong gaskets anyway. It soon became apparent why -- it took three different parts clerks and a service manager, plus myself, combing through three different parts books, to find the numbers for the correct parts.
The issue has to do with the turbo being top mounted, with the oil drain coupled directly to the blower cover. Most of the exploded diagrams show an oil return tube, which I (and most bus installations) don't have. The seal for the oil drain is listed on some parts manifests, but it does not show on the diagrams, nor is its function listed on the manifest.
Nearly two hours later, we had tracked down part numbers for the oil drain seal and the blower adapter gasket; the exhaust flange gasket was the easy one, and they had produced one within the first few minutes. They turned out to also have the drain seal in stock. Unfortunately, the blower adapter gasket was not, nor did anyone else in town have one. At least this was the least critical of the three, and it can be replaced later if need be without having to remove the turbo.
We loaded the new turbo, the gaskets, and a gallon of 40-weight back onto the scooters and headed back to the casino, where I arranged to meet Jim the mobile truck repair guy. He was so efficient at getting the thing out, I decided to enlist his help putting it back in, too.
As it turned out, he had to wrestle with it for nearly two hours to get it back in. Everything is tight in my engine bay, and getting the exhaust flanges, the exhaust pipe, the intake elbow, and the blower adapter to all line up and cooperate was a challenge. I had to open up the access hatch through the radiator intake so we could tug on the exhaust plumbing, and Jim ended up loosening the turbine and compressor housing clamps on the new unit to tweak the clocking to get it all to fit. eventually we had it all back in place, and then started pouring 40-weight into the bearing through the oil supply hole.
Hmm... the oil does not seem to be going in. Nope -- it's just sitting there in the fitting. Even spinning the compressor wheel is not getting any oil to drain. After probably ten minutes of this, we decided the tiny orifice at the oil supply was clogged, most likely with assembly grease. We threaded an air fitting into the supply hole, and a quick blast of compressed air cleared the obstruction. After pouring a few ounces of oil into the bearing from a squeeze bottle, we re-attached the oil supply line.
From the rear switches, which allow for cranking the engine with the fuel solenoid closed, I bumped the engine around a few times in short pulses -- so many folks have warned me about a blown injector tip, that I was worried a cylinder could be full of fuel and hydraulically locked. But there was no resistance at all. So I cranked it three or four times for close to ten seconds apiece, closely spaced, to get some oil flowing up to the bearings and purge any air from the supply line. Then I set the switch on run and cranked it again, and it immediately lit off.
I noticed two things right away. The first was that I did not get a big puff of white smoke when it started -- we've been seeing such a puff of smoke on start-up for several months now, and it is one of the symptoms I have reported every time we've had anything done on the engine. We've now fired up three or four times today, with no smoke evident on any start. The second was that things sounded smoother than they have in a while, and the exhaust looked and smelled cleaner. All good signs.
After checking for leaks, shutting down, and rechecking clamp tightness, we declared victory and I paid Jim for his time -- two hours, plus travel. We then buttoned the coach up, loaded the scooters, and set out around the parking lot on a low-speed test drive. Kevin (Zeroclearance) had strongly recommended getting everything up to operating temperature (and then back down to cold again) three times before putting any real load on the turbo, and so we kept speed and acceleration down, watching the boost gauge to try to keep it under 2 psi (we hit 3 psi occasionally). I stopped occasionally to check for smoke and read the temps with an IR gun, but all was normal at every stop, other than oil spitting out of the exhaust and the muffler drains. I expect to be puking oil for the next fifty miles, until whatever's left in the exhaust and the airbox finally burns off or spits out.
After half an hour or so of "road" time (we made it as far as the historic Rio Puerco bridge), during which I noticed subjectively more power and less black smoke than we've had in quite some time (even at these very low boost levels) we parked for the night in the casino's RV lot, blissfully out of range of the incessantly idling trucks. After dinner, when all had cooled down, I popped the hatch to check all the clamps and look for leaks.
What I found was that Jim had tightened the clamps on the outlet hose with the jackscrews too close to the steel supports for the top of the turbo compartment. We've had problems in this area before (see http://ourodyssey.blogspot.com/2005/05/duct-between-turbo-and-blower-showing.html (http://ourodyssey.blogspot.com/2005/05/duct-between-turbo-and-blower-showing.html)), and so I loosened the clamps and rotated them 90° for clearance. When I did this, I noticed two things; one was that there was a ripple in the hose, because the clocking of the compressor housing had the outlet just a tad out of line with the blower adapter inlet. The second was that the hose looked torn in exactly the same spot as shown in the photo I just linked.
With both hose clamps loose, I was able to loosen the compressor housing v-band and inlet duct, then gently tap the volute around a couple degrees with a plastic deadblow, taking care of the first issue. Without removing the adapter, however, I could not remove the hose to see if the tear went all the way through. Moreover, I was afraid that I could worsen the situation by trying to remove the hose.
What I ended up doing was to tighten up all the clamps, fire up the engine, set the high idle to get enough compressor speed to bring the pre-blower boost pressure up above atmospheric (at extremely low compressor levels, the blower can clear the air as fast as the compressor provides it, yielding 0.0 boost, or just atmospheric pressure). Then I sprayed the hole with soap solution, just as one would when looking for air line leaks. No bubbles, so we think the hose is intact, and the tear we can see is just in the outer jacket. We will order a new hose and replace it as a precaution the next time we pass a Detroit shop.
As long as the engine was now already running, I closed up the hatch and we let it come all the way back up to temperature before shutting down for the night. Tomorrow, we will do one more hot/cold cycle before we leave; during that warm-up I will connect my DDR and run the injectors, just to be certain we are firing on all cylinders, to borrow a phrase. If all seems well, we will clear out of here and resume our previous route west to Phoenix.
At this writing, it seems as though we did not have any deeper problem, such as blown injector tips, or catastrophic destruction of rings or valves becoming FOD and hitting the turbine. I can't rule out FOD as a cause -- it's possible something such as a rust flake or a clot of coke got knocked off into the exhaust when S&S in Farmington repaired an exhaust clamp, for example. But I am inclined to believe that what really happened here is that the turbine wheel became slightly imbalanced many moons ago, possibly due to FOD but also possibly just due to manufacturing tolerance issues -- it was a rebuilt unit to begin with. Over time that imbalance caused irregular bearing wear, and the turbine has been wobbling in the bearing for several months. Eventually, the edge of the journal scored the shaft, creating a weak spot right where the turbine wheel attaches. It was then only a matter of time before some combination of heat, load, and speed caused the shaft to shear along the score line. The extensive damage to the turbine blades then occurred almost immediately as the now loose turbine wheel ricocheted around the housing.
I will report back here once I have actually brought the engine into the powerband and the boost levels up into the high teens, and let you know how it's running. But based on testing so far, I believe we will be back to 100% normal operation.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean, it's good news that you got the turbo mounted and the engine running. Who knows you might be now at 105% vs the less than 100% that you have been running lately. BTW, how much oil did you pour in to bring it back to normal?
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Sean, glad you had no internal problem .
I hope you never need it again but here are engine numbers to put in your files that will show the parts for the mounting like yours
model 8087-7087
serial 8VF 128885
good luck
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Kevin -- I put a gallon in, and I look to be maybe one or two quarts low still.
Clifford -- I have the model and serial number for my engine. Unfortunately, since Detroit sold the two-strokes to MTU, the computers that the distributors use to pull up the builds are now running on MTU's system, which still has lots of kinks.
We were able to call up the build list for my engine, but there are no exploded diagrams. We had to go back to the printed books. Those seem to be a bit buggy, too -- when we finally found the page with the correct blower cover, it showed the two mounting holes for the turbo, but the oil drain hole was missing from the picture. The oil drain seal was not shown on that page or on the page for the turbo itself; we finally found the part number on the turbo parts list, but it is just described as "seal" -- we only figured it out based on dimensions.
Since the blower cover page was missing the drain hole, and also showed a screen that doesn't exist, we kept doubting whether it was the right page, and so were unsure of the gasket number shown there,
I will be glad when MTU gets the kinks out.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean, that be S & S thing and not MTU I never have a problem getting both screens the one for the the turbo an the other under the air horn from WW Williams good luck
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Sean, that be S & S thing and not MTU I never have a problem getting both screens the one for the the turbo an the other under the air horn from WW Williams good luck
Clifford what does a horn have to do with the turbo?!?!?!
Jest kidd'n but there are those who haven't got a clue as to what you mean by the air horn! ;D
;D BK ;D
Oh I know better, but you guys know me I never pass a chance to be witty!
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This will be, I hope, my final update on the turbo repair.
Tonight we are at a picnic area on US-60 west of Quemado, NM, some 140 miles from where we started the day. Aside from blowing huge quantities of blue smoke at the beginning, tapering off steadily throughout the day, and the fact that the whole coach now smells like burning oil, we have had no problems or issues. I have tried to be fairly gentle on the turbo while we seat the bearings and seals, but, subjectively, we have normal power now, at least as normal as it gets at 6,000-7,000' altitude.
This morning, during my third and final warm-up/cool-down cycle, I plugged in the DDR to check on everything. Specifically, I checked injector response, which looked good on all eight cylinders, ranging from 1.07 to 1.17. I also ran the injector cut-out test on all cylinders at idle as well as 1,000 rpm, and all injectors elicited a response, with pulse width increasing by 0.2 to 0.4 for each cylinder.
For those unfamiliar, what this latter test does is to first report the amount of fuel being provided to the cylinders in the form of "pulse width" (PW), the amount of time the injectors are commanded to inject. Then it shuts off the injectors one at a time and reports the PW as each injector is off line. The idea here is that when a cylinder that was contributing real work gets turned off, the DDEC will have to increase the PW to supply more fuel to the rest of the cylinders to carry the load. If you turn off one injector, and there is no resulting change in PW, that means that that cylinder was not doing any work, which could mean a bad injector (or a number of other problems).
I am interpreting the results, being fairly consistent across all cylinders, as meaning that I still have all eight injector tips, and all the exhaust valves are intact. I'm not conversant enough with these sorts of tests to rule out any other problems (low compression, marginal injector, etc.), but I am fairly confident at this point that the turbine failure was not due to FOD originating in the engine.
While we were driving, Louise reported that the turbo sounded "rough" and that it made much more noise than the old one. That's cause for some concern, but not too much, yet -- I still have not replaced the heavy exhaust blanket over the turbine housing, nor have I secured the hatch (which involves caulking it, screwing it down, and replacing the 1/8" vinyl flooring over the top), and both of those things would attenuate the sound considerably. In fact, Louise later reported that the sound was lessened when she stood on the hatch.
I have been asked whether there might have been something I could monitor that would have provided early warning of this impending failure. To be honest, I don't know. I don't suspect I would have noticed anything unusual on an oil temperature gauge, or even exhaust pyrometers, that would have led me to check on the turbo. Even the boost readings seemed normal right up until failure, and any changes in those sorts of readings would have been so gradual over time as to be unnoticeable -- sort of like putting a frog in cold water, and then boiling it. That said, I sure do wish I had pyrometers. Separate pyrometers for each manifold would have given me the confidence ahead of time that I did not have a single-cylinder failure of some sort. Also, they might have alerted me that the exhaust was getting hot enough to melt things (turns out, the thermoplastic wires were OK -- I only melted the slit loom).
Again, I would like to thank everyone here for their help -- this board is a fantastic resource, and it is this kind of selfless outpouring of assistance that has kept me here, usually answering questions, long after my bus was completed.
-Sean
http://OurOdyssey.BlogSpot.com
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Sean,
You get back what you put in......
I think I speak for a lot of us here who have benefited from your posts over the years.
Thanks for such a complete and well written account of your trouble. While we hope no one has to go through it like you did, it will be invaluable to anyone who has a similar problem.
TOM