BCM Community
Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Brian Diehl on August 03, 2010, 07:15:15 PM
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I'm going to be taking my family on a trip to the Oregon coast in September. I need to find a good alignment shop along the way.
Here is the problem: I've had a constant pull to the right in my bus since day one. I have replaced all bushings, shocks, and the driver's side king pin. I have had a toe in alignment done as well. The tie rod ends are in excellent shape also. I've rotated tires, replaced rims, and completely replaced tires on all axles during my ownership. I have not noticed any uneven tire wear either on the fronts or tags. The problem still exists. The pull is such that if I drive on the opposite crown of the road (the fast lane) the pull evens out against the opposite crown almost exactly to the point I don't need to provide any correction. However, I'm still providing some left steering correction even on a left angled crown.
Our locally recommended alignment shop is unable to tell me why it still pulls to the right.
So, can anyone recommend a really good shop somewhere in these states I could book an appt. with to get this problem diagnosed?
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Somebody will recommend that alignment shop up in Eugene, OR. I have heard good things about them.
JohnEd might know. Clifford for sure does, and I could probably dig up the name of the place.
I have heard that they are the best....but I don't know.
FWIW
God bless,
John
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Brian, did you try Precision Frame in Elk River?
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I'm guessing you've already asked JD?
;D BK ;D
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Somebody will recommend that alignment shop up in Eugene, OR. I have heard good things about them.
That would be Kaiser, and that's where I'd go if I was going to be near Eugene.
-Sean
http://OurOdyssey.BlogSpot.com (http://OurOdyssey.BlogSpot.com)
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It is Kaiser and Dick Kaiser has a rep that extends all the way to Clifford. Dick was in semi retirement for a year cause his wife had terminal cancer. He is back at work as I understand it.
Eugene is only an hours drive from the coast you will be traveling down. Dick will run elect out to your bus if you stay over night. I am sure there are other reputable shops along your route.....Kaiser Brake and Alignment in Eugene Or is just the only one I know of. Maybe Clifford can give you alternative suggestions.
That pulling problem has turned out to be in the rear end suspension/alignment with a few folks I have heard tell the tale. I am one!
good luck,
John
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Brian,
JE touched on it. I would definitely check all the radius rod bushings in the rear. If they're worn, they will make the bus handle and steer funny.
Bob
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I second the advice to check out the back of the bus. On an MCI like mine, about the only things that are actually adjustable is the toe in, all the rest is set in the axle. Castor is most known for causing a pull, MCI puts unequal camber on the front, side to side, to accommodate the crown in the road, but you can't adjust it, really. I did have an issue with centering of the steering box that cleared up some pulling and wandering issues for me when I fixed it. Sheppard steering box, the drag link was well too long (almost an inch too long) so when driving straight the steering box was well off center. You have to pop one of the drag link ball joints off (at the steering knuckle is easiest), set the wheels dead straight, center the steering box per the manual (witness line on the pitman arm shaft at 90 degrees to the input shaft) and make the drag link length such that the ball joint slips into the steering arm on the knuckle perfectly. At least that's how I did it :D
Brian
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Sorry all, I should have been more specific. All radius rod bushings - front and back - have been replaced.
Yes, JD recommended the shop I went to.
No, I did not try Precision Frame in Elk River. I had not heard of them. What has your experience with them been?
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Brian, I have heard that switching the tires side to side at the front can help, never tried it but not hard to do... Also, I was honestly amazed at the difference when I centred the steering box.
Brian
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Brian, I have heard that switching the tires side to side at the front can help, never tried it but not hard to do... Also, I was honestly amazed at the difference when I centred the steering box.
Brian
Thanks Brian. Yes, I have done the swap multiple times. No difference.
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Brian,
I suggest you try one of the shops that are on your way. Then you can eval the effectiveness of their work. If you still have the problem you can ask Kaiser for some sort of guaranty of success before having them take their shot. Call before hand and talk to "Dick Kaiser" personally. Mention the people that have recommended him and that you got his name from us and that might get you in earlier but the quality of work wont change as that is always high.
Yours is the typical Kaiser folk lore......everybody else failed many times and Dick fixed it. Common story. Should he fail that would be news worthy of print as well.
Good luck
John
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No, I did not try Precision Frame in Elk River. I had not heard of them. What has your experience with them been?
They weren't able to fix my wandering issues, but they checked things nobody else did. I had them send my steering gear out for rebuild and that helped somewhat.
These guys are well known in the RV world for fixing steering issues. They even travel all over to big RV rallies to fix problems on site.
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A few years back I was told I needed new kingpins. When I finally got it together to have the job done I tried to contact the person that told me I needed the kingpins but he was out of business. I called Kaiser in Eugene, Or. and told them I needed new kinkpins so they ordered them and made me an appointment. When I got there they told me I didn't need the kingpins I just needed a proper alignment. That was a couple years ago.
Jerry
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You will never regret going to Dick Kaiser from 1996 to 2000 that where all the Prevost converters sent theirs to fix the front end problems with the indenpent front suspension seen those in there as far away as Florida it will be right when it leaves all 3 axles
good luck
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Thank you everyone for your replies. I have an appointment on the 13th with Dick @ Precision Frame and Alignment http://www.precisionframe.com/ (http://www.precisionframe.com/). They believe they can figure out what is wrong and help me get a solution. I'll update this once I learn what they have to say.
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First of all, the experience I had was very good! Dick is very knowledgeable about what he does and knows how to educate his customer and bring the customer in on the investigation stage of the alignment work. It is great to be able to be walking around speaking with him as he is setting things up and checking each axle. Here is what I learned:
1) The front axle alignment is just about perfect.
2) The drive axle is pointing to the left such that from the drive axle to the front axle the thrust angle is offset by 2"
3) The tag axle is point to the left such that from the tag axle to the front axle the thrust angle is offset by 3"
This perfectly explains why the bus is always pulling to the right.
The charge to fix the drive and tag axles is $400 should I choose to do it. Now I just need to decide if I want to have it fixed.
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The charge to fix the drive and tag axles is $400 should I choose to do it. Now I just need to decide if I want to have it fixed.
That's a great price and you will not regret it -- just do it.
You could save that $400 in tire wear alone.
We had a similar drive-axle alignment issue and I'm glad we had it fixed, even though we paid more than that at a Freightliner dealer. Coach handles much better now and tire wear has dropped significantly.
-Sean
http://OurOdyssey.BlogSpot.com (http://OurOdyssey.BlogSpot.com)
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Hi Brian,
Thanks for the update. I think a lot of us would be interested to know what work would be required to fix the problem. It seems to me that your $400 would be well spent for the sake of driveability and reduced tire wear, but it is easy for me to sit here and spend your money.
Good luck with your decision, Sam MC8
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I would not hesitate for a second. I vote with the "just do it" crowd. I just made a similar upgrade in steering performance to my bus, the different in enjoyment is astounding.
Brian
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Brian,
Welcome to Eugene. Really pleased to hear that Dick resolved your problem. I wouldn't pass up the chance to have him correct the problem. Now in the most remote possibility that Dick missed something......he will correct that also. You pretty much have a guarantee that your problem will be fixed when you leave town.
Can anyone share with us "how do you check the tag and drive alignment?" How do you adjust it?
Thanks,
John
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JohnEd, Brian went to Elk River, MN and had a different "Dick" work on the alignment (not Dick Kaiser).
I too, would like to know how they adjust the thrust angle.
I have had on my list of articles to write, an alignment process that the racers use called "stringing the car". Here you put a tight string along the bus making the string parallel to the side of the bus. You then measure in from the string to measure thrust angles on the rear axles and tow-in on the front axle. I have not had time to set up the system to verify it works on a bus and to take pictures.
Jim
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I wouldn't hesitate for a second. Do it!!!!
You won't regret it. Just do it!!!
God bless,
John
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Jim,
Thanks for getting back to me and clearing that.
Stringing sounds good. I asked cause they aligned these pups before Bear Alignment Sytems happened, let alone all the lazer stuff.
Tow is measured by spinning the tire and coating it with quick dry paint. Then with the tire spinning you rub a sharp ice pick type tool against the painted portion of the tire to scribe a sharply defined line around it. Using a square leaned up against the tire and carefully placed against ech scribed line you measure the front distance between lines. Do the same for the rear of the tire and take the difference in the measurements for the tow. The weight of e vehicle must be on the tire so the jack needs to be under the king pin or other strong structure o the underside. You can measure the camber with a level and measure the amt that it must be moved to get it perpendicular and with geometry you can compute what that distance needed to correct must be. You measure at the rim and use that rim diameter and the off vert and use trig to find the angle. Caster... I got nutt'n. Sure hope you get this all worked out as it is going to be useful.
John
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Brian,
For $400, I would do it if I had confidence they knew what they were talking about and could fix it properly. I'd probably have them explain the correction procedure first.
Please let us (me) know what you decide and if you do have it fixed, how it goes. I really should get the alignment on mine looked at as I've never had it done. Mine drives
pretty well, but lately seems to require more correction. Could be the larger tires I just moved to the tag from the steer. They were cupped and worn on one side (which is
why I think I should get the alignment checked).
craig
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JohnEd, the toe-in method you mention has worked well for smaller vehicles as far as I can tell. However, the reading I have done suggest that you need to drive the bus a few feet forward to get all of the clearances "organized" the way they would be going down the road. I think that just jacking up the wheel and then dropping it down could give you some false readings.
I made a bar out of electrical tubing with a nut welded on each end. I thread in some thread-rod into each nut. I then drive the bus forward on the shop floor several feet and carefully place the rod in front of the suspension and tighten the thread-rod so that the bar is gently seated on a very specific place on the tire. Then I move to the back of the suspension and place the rod against the same place on the tire. There should be about a 1/16 to 1/8 clearance on the rod. I have aluminum wheels, so rim run-out is minimal. I have repeated the process with the tires rotated to a different location and get reasonable repeatability. I have a very old alignment set (mostly bought for the turn-tables) and it used the rod method. Worked fine for the older cars.
I have used that method on a bunch of cars and the bus. The bus handles very well and tire wear is normal.
Many "vintage" race folks use the string method to adjust toe in. My plan is to string the bus and check the toe-in by measuring off the string on each side (will take a bit of simple math to take four measurements into consideration since the wheels will not be perfectly straight) and compare it to the rod measurement.
The use of a level will indeed give you a measure of camber. At least it will tell you if it is reasonable. Caster is a value that we can't measure with simple tools. I have a fairly modern set of camber/caster gauges and turn tables for cars, but would not attempt to try to adapt them to the bus.
As home mechanics, we can fairly easily adjust toe-in. Anything else should be left to the experts.
Jim
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I have increased the tow-in till I got a stable ride on the freeway. Of course the shop had already set to the "correct" position. I agree that you need to roll the vehicle after setting it back down but that applies only to the way it was raised. If you lift from the king pin bottom point the suspension comes down "relaxed". If you lifted by the frame then when it sits down your wheel and suspension will be in a bind and you need to roll the vehicle to "relax" that binding.
When I had a low floor jack I didn't bother with rolling. If I had to use a tall jack I rolled the car or the readings were crap.
I hope you get that set of instructions done and printed for all of us. Even if there is onlyone method described and it can be followed by all then this problem will be solved. I think that effort needs to include some data on verification of the condition of bushings, bearings, Kings, etc. Stuff that you need to do BEFORE you start twisting bolts in a suspension alignment effort.
Jim, good luck with this.
John
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"Stringing" a race car is used up to quite high levels of racing, and is certainly used by pro teams all the time. It starts with a flat surface to put the car on, adjustable platforms are used in the field and are levelled with laser systems, or with beams and machinist's levels to within .010" to .020". Each car will have a custom rig made for it that fits into the chassis with index pins for repeatability. The string is high tension test fishing line, about .020" in diameter. The line forms a perfect rectangle to a machined accuracy of a few thou. around the car, and you measure to the wheel rims if you are in a hurry, or to machined setup plates if you are trying hard. Wheel rims aren't really all that accurate, a good rim will have ten or twenty thou run-out. You measure from the edge of the string to the rim or plate using a digital caliper, and you can get accuracy down to a couple of thou if you are good. All this sets the the width of the car and the toe. Digital levels or protractors are used to set castor (on machined surfaces on the uprights, usually) and camber, and digital gauges are used to set ride height. Your setup platform also includes digital scales that allow you to measure each wheel load to the pound.
When I had my bus aligned with a two axle Hunter laser setup, they basically created the box with lasers attached to each wheel. They measured the alignment of the drive axle to the steer, measured toe, castor and camber with levels, but I did not notice them doing any measurements to measure offset of the axles in the chassis. But in general the process they used on the bus and the process I use on a race car were really very similar, just different tools to accomplish the same goals.
Brian
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Brian, I was hoping you would jump in. Most of my experience has been in the vintage car area, but I had a suspicion that it was used on other levels of racing. Done properly (as noted in your post), it should apply to any vehicle.
I want to do the process to make sure it scales up to a bus. I am concerned about getting 40 plus feet of string tight enough to make meaningful measurements. The thought of using fishing line makes good sense. The lighter weight should minimize the catenary affect over that large distance. The good part of the process is that the long side length of the bus will make a good reference.
One of the main reasons I want to string my Eagle is the fact that the bogeys can get out of alignment and I want to check that. On an Eagle, the alignment (at least reasonable adjustments) can be done with shims.
My opinion is that alignment of our buses does not have to be done down to the thousandths. A race car needs that level of accuracy.
Guess I had better get on with trying the process and documenting it ::)
Jim
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Jim, I used the 20 dollar laser from HD or Lowes to check mine pretty good little gadget for checking the boogie also
good luck
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Jim, find the center of your bus, front and rear. Buy two 2" square .100" wall aluminium tubes that are two feet longer than your bus is wide, mark the center of each tube accurately. Attach the tubes, probably to the bumper tops or something, so that you have the centers aligned. Mark four spots on the tubes as close to the sides of the bus as practical, exactly the same distance from center, drill holes carefully, and put in some self-tapping #8 screws, leave them sticking out 1/4". Drill four more holes inboard of the ones you just did and put in four more #8 screws sticking out same as the first but no need for extreme accuracy as the string will pivot on the accurate screws and be tied off on the inboard screws. Go to the fishing store and buy some fishing line, two 50 ft rolls or one 100 ft roll (I don't fish, so I have no idea about fishing line), but get the highest test you can, 100 lbs would be good, and tie a loop in one end. Run the other end around the pivot pin, and slowly tighten the lines equally on both sides, you are trying to avoid cocking the cross-tubes by having unequal tension between the lines. Now you have your box.
Go to a tool store and buy a high quality steel ruler with graduations down to 1/16" inch. That is not very fine, but it is a fact that you can easily measure to .015" with such a ruler, by integrating the spaces between the lines. You can be "dead on", half way between", or "mark-plus" or "mark-minus". Now me personally I have to get my special reading glasses that I bought at the drug store to read that, but I need them to read micrometers these days too. I finally figured out that old guys invented digital readouts... If you are a machinist like me, you may have a 12" dial calliper that would work better, reading to 1 thou, but it is amazing how accurate you can be with a ruler and string, trust me... The funny thing is that lasers aren't considered accurate enough for this in the race car world, since the beam is about 1/8" thick, so old trumps new in some things... Very high end equipment obviously has better accuracy than that.
Now you can start. rough-center the steering, and then adjust it so you get the same reading difference front to back on each side. It's difference that you are looking for, since the axle will not be centered accurately unless it's a flluke. Read to the wheel rim, it's as accurate as you really need. If you have the fronts 1/16" further in than the rears on each side, then you have 1/8" of total toe in. It is important to do this with the steering centered so Ackerman effect is negligible (Ackerman is a designed in condition that the inside wheel in a turn steers more than the outside wheel).
Now go to the back, and make your measurements. The drive axle should have no toe, to the accuracy that you can measure it. If it does, it is cocked in the chassis and steering the bus. If you know trigonometry, or have a handy kid who does, you can calculate the amount of cocking. At that point you can start to do other things like measure wheelbase and so on. The tag axles can probably be all over the map as far as toe and such is concerned, and this is a good way to measure that. All the time, make sure you aren't measuring dents in wheels. If brand new race wheels have 10 or 20 thou run-out, and they do, I have no idea what an old 22.5" bus wheel with half a million miles on it will have for run-out. If you find something that bothers you and you want to eliminate run out, just jack up the wheel and spin it, and find two spots opposite each other that have the same amount of run-out. Two errors the same equals no error at all...
Camber is the in or outward tilt of the wheels, on my bus it isn't adjustable so I ignore it but you can measure it by determining the level of your ground, the vertical inclination of the wheels and figuring the difference. It's notated in degrees off 90 degrees to level, negative is in at the top and positive is out at the top, so if your ground slopes down to passenger side by 3 degrees and your passenger side wheel is two degrees off dead vertical tilting out at the top, you have one degree of negative camber. I use a digital protractor to measure these things as I don't remember my trig and I usually don't have a kid handy...
Castor is the forward or backward tilt of the steering axis, usually a kingpin on our buses. The lower pivot point leads the upper pivot point so the king pin tilts backwards at the top. This really helps the bus steer straight, and gives it self-centering action when in corners. Again it is not easily adjustable on my bus (you could but you'd really have to want to) and it's built in to the axle. If you really want to measure it there are two ways, one easy, one a little harder. The easy way is to use your level or your digital protractor to find the level of your ground front to back, then take an eyeball look at the tilt and measure it with your protractor by eye. You can actually get really close this way if you practice a bit. I can set castor on a race car by standing over the front hub and looking down at it. The other way is with turn plates. Castor affects camber when the wheel is turned so if you turn the wheel exactly 20 degrees from center and measure the camber change and consult a chart or a computer program, it will tell you what the castor is. What is more important than an actual number is that they are close to being the same side to side so the bus steers straight. Factory settings on buses sometimes have different castor and camber settings side to side at the front to counteract the steering effect from the camber of the road, at least I assume that is the reason.
Hope this amuses someone, the benefit to me is I had 20 minutes inside in the cool when I should have been outside in the 90 degree heat index sun doing chores...
Brian
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Darn Brian, now there is no need for me to write the article ;D Great input.
Clifford, I like the laser idea. I had not thought about the width being an issue (per Brian). Probably not a huge issue for our needs (as opposed to race car needs). I have such a device and will play with it when I set it up.
Brian, the only issue that I want to pick away at is the need to measure the center of the bus. First of all, it would be really hard to do that (not to sure what would be a good reference - especially for those of us that don't have frames). Second, I would think that the side of the bus would be a pretty good reference.
Jim
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If you are sure the side of the bus is accurate and has zero taper, sure. All you are trying to do is construct a really really accurate rectangle. Going from center is only the easy way to do that if you happen to know where the center is. I personally don't think my bus is accurate down the sides to under a 16th of an inch, and to use this technique you need to be able to measure differences in toe to a minimum of 16th of an inch. But - try this. Get your tubes on, wrap the strings on and move them around till you have them parallel to the sides of the bus all the way along, to a 16th. On both sides. Then measure the distance between the strings front and back. If the front is the same distance apart as the back, then the sides of the bus are parallel and you have built a rectangle as opposed to a parallelogram or a rhombus or whatever you call it. If they aren't equal, you have a non-parallel sided shape that you can make into a rectangle by moving both of the strings at one end only in or out by accurately equal amounts (half of the total difference each string, obviously) to match the other end perfectly. Now - you can proceed as discussed and have at it. You realize that if you do this and happen to arrange things so the strings are parallel to the sides and happen to also be the same distance from the bus on each side, taking the next step and finding the center of the bus is kind of trivial...
Some people use jack stands to tie the strings to. I thought of that, and discarded it because ideally you want the strings at center of axle height and that's kind of high for a jack stand. The other thought was that to get the strings really straight you will need to put around 50 lbs or more of tension on them, and that is going to be hard to control on free-standing stands, but dead easy with the tubes clamped to the bus. But there is no reason not to be creative. And since me writing this gives the website the right to use this and publish in any format, there is no reason not to use the ideas in your article. It's not like I dreamed this up whole one night, this has been around since Archimedes...
Brian
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Brian (Diehl),
If it were me, and I had your $ ;) I'd have ALL my buses done!
Seriously now, if he will guarantee that it will fix it! I'd have him go ahead and do it! (I'd let him know if it don't fix it, that he can pay Dick Kaiser to fix it right!)
Or on the other hand you could call Dick Kaiser and see what he thinks of it, and maybe just have him do it while your out there!
;D BK ;D
Be safe and enjoy the trip!
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Jim, As you know I am doing some major modifications to my 15 and I need to know that ever thing is straight at all times. To set the parallel lines I use four saw horses and weight them down so I can pull the string tight. That way I can set the horses behind and in front of the bus so I can measure to set the parallel lines. It takes a little time to set the strings because you want them to be straight with the bus but it can be done. Castor as Brian says is the angle of the King Pin. I use a digital level to set the king pin. Remember the wheels must be set true centered to do this. When I am all done I will take it to a shop to set it on a machine but with the way I am doing it now I can get it close. Good thread.
Thank You Wayne
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I have followed this thread with great interest. I became obsessed with the alignment of my rig.
I had two shops in Fort Worth work with it, and both times I was worse off then when I started. Short story is they want to set it up with too little toe in, and one shop tightened the steering gear box, making it impossible to keep in the road.
Long story short, I measured the thrust angle of the rear axle using a modified version of the string method used above. I did establish a centerline of the suspension, and I did pull my perpendicular strings to 10 feet longer on each side of the coach to cut down on measurement error.
I measured my thrust angle that way as 0.06 degrees to the right.
A year later, just for grins when I was at the Newell factory, I had them do an alignment. Cost me 400 bucks for them to tell me the thrust angle was ..................0.06 degrees to the right. It wasn't a total waste of money since they did adjust the tags.
The point is that if you are careful you can get VERY accurate results using string and trigonometry.
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Thanks to everyone being so willing to spend my money I have decided to have RV Frame and Alignment fix my axle alignment problem. I'm very pleased with the level of service provided so far. Dick Lorntson stayed late to allow me to get the bus up to him yesterday after the end of my normal day. He is anticipating needing today and tomorrow to get both axles aligned properly. I did not here anything from him today. Given his communication style I've witnessed to date I would say this is a good sign and that he has not run into anything bad in his efforts so far. I forgot to mention in my last post I was really surprised with the bill to diagnose the alignment problem. Dick spent an hour and forty minutes going through all 3 axles with me last Thursday looking to find out what was causing my alignment problem. He walked me through every step of the process and collaborated with me on the diagnostic and parts replacement steps I've already taken trying to narrow down the problem. No came the surprise .... the bill was $75. Remember he spent almost two hours with me. I was dumb founded. I asked him about why the bill was so small yesterday when I dropped off the bus and his answer was simple ... I charged you what I thought the value of what I provided was. Wow and Wow. Of course the proof is in the pudding. I'll update the thread again once I get the bus back with the results of his efforts.
Here is his web site in case you are interested (his wife runs the website!): http://www.precisionframe.com/ (http://www.precisionframe.com/)
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Brian,
Call me before you go pick up the bus. I might like to meet you there to listen to what he has to say about yours,
and maybe talk to him a bit about mine. If this works out, I may want to take mine in
to have it looked at.
craig