Author Topic: strange turbo sound??  (Read 5657 times)

Offline David Anderson

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strange turbo sound??
« on: April 05, 2019, 07:08:57 PM »
I stopped the bus from the engine bay this morning and noticed somewhat of a light grinding sound
from the turbo as it spun to  stop.  I don't know if it's normal or not.  Everything seems normal as I drive the coach. 
No change in power, no smoke from the tailpipe.  It may be nothing, but I'd like you guys to hear it and give
me an opinion.  I uploaded a 30 second video on youtube.  Listen to it wind down for about 3-5 seconds after I turn
off the coach. 

https://youtu.be/ds6GnuPxeCw

David

Offline luvrbus

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Re: strange turbo sound??
« Reply #1 on: April 05, 2019, 07:17:51 PM »
Pop the exhaust and check for shiny spots sounds like it getting to the end of life 
Life is short drink the good wine first

Offline chessie4905

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Re: strange turbo sound??
« Reply #2 on: April 05, 2019, 07:39:02 PM »
With exhaust unhooked, grasp the stem or tip of exhaust impeller ith your fingers, not with pliers and attempt to wiggle it up and down. If it moves up and down and feels loose, avoid driving it till you replace or repair it. Once they get sloppy, it's not long for impeller to start desenagrating. Since the intake side and exhaust side impellers are mounted on the same shaft, the intake impeller could make contact also or first, sending metal into engine.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline David Anderson

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Re: strange turbo sound??
« Reply #3 on: April 07, 2019, 04:24:43 PM »
I am very fortunate I happened to hear this at the back of the coach while shutting off the engine.  I got some pieces off today, can't see the impeller yet, but felt it with my fingers and it has noticeable end play.  It is all coming off and going to the shop. 

I did find a pipe that is bad.  A portion of the flange is gone.  Pictures attached.  Where can I find this elbow?
David


Offline luvrbus

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Re: strange turbo sound??
« Reply #4 on: April 07, 2019, 04:28:59 PM »
take it to a truck muffler shop and have a flange weld on or they can make the pipe
Life is short drink the good wine first

Offline David Anderson

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Re: strange turbo sound??
« Reply #5 on: April 08, 2019, 04:27:28 PM »
Oh man, oh my, It took me all day to get the turbo off.  Lots of heat. lots of penetrant, more heat, tap, tap, more heat, etc.  I broke one bolt.  Of course it is in the threaded part of the cast iron flange.  I have it drilled out almost to the threads.  Couldn't find any of my easy outs, so I'll buy some tomorrow.  I filled the hole with ATF and acetone mix which works very well as a penetrant, (a youtube suggestion)  I'll let it soak overnite.

I called M&D diesel in San Antonio
https://www.mddistributors.com/san-antonio/

They can rebuild as needed.  I will drive it up there tomorrow and press on with this.  All the turbine blades look good, but lots of end play on both sides, but not hitting any part of the housing.  I'm very fortunate to find this before it touched the housing.  I read Sean's turbo explosion in the Odyssey in the archives. 

https://www.busconversionmagazine.com/forum/index.php?topic=12676.0

There is no way I could have done this on the road without torches and other tools I don't carry.   

Any great hints at getting the bolt out would be appreciated.

David

Offline Utahclaimjumper

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Re: strange turbo sound??
« Reply #6 on: April 08, 2019, 05:04:53 PM »
You are usually better off to leave it to the pro's to laser it out with out damage to the threads.>>>Dan
Utclmjmpr  (rufcmpn)
 EX 4106 (presently SOB)
Cedar City, Ut.
 72 VW Baja towed

Offline Utahclaimjumper

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Re: strange turbo sound??
« Reply #7 on: April 08, 2019, 05:05:09 PM »

 double post
Utclmjmpr  (rufcmpn)
 EX 4106 (presently SOB)
Cedar City, Ut.
 72 VW Baja towed

Offline buswarrior

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Re: strange turbo sound??
« Reply #8 on: April 08, 2019, 05:53:39 PM »
ATF and acetone

Old school Weasel Piss.

Excellent mixture, well used and recommended by many old codgers who are dead and gone.

50:50 mixture, safety first, label your bottles!

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline luvrbus

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Re: strange turbo sound??
« Reply #9 on: April 08, 2019, 06:42:21 PM »
M and D is good outfit I install 12 of their turbos last year on some generators,soak the bolt with penetrating oil had heat it that will draw the oil into the part let cool and it should come out easy   
Life is short drink the good wine first

Offline chessie4905

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Re: strange turbo sound??
« Reply #10 on: April 08, 2019, 07:11:27 PM »
Whatever you do...do not snap off the easy out! You will have remove a broken one with a carbide bit or Burr.btdt
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline daddysgirl

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Re: strange turbo sound??
« Reply #11 on: April 09, 2019, 07:35:40 AM »
ATF and acetone

Old school Weasel Piss.

Excellent mixture, well used and recommended by many old codgers who are dead and gone.

50:50 mixture, safety first, label your bottles!

Happy coaching!
Buswarrior

Yea, what he said with one minor caveat...
Acetone is nail polish remover...DO NOT use it on painted surfaces.
Otherwise, nothing works better.
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

Offline luvrbus

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Re: strange turbo sound??
« Reply #12 on: April 09, 2019, 07:42:29 AM »
Acetone will just harm cheap enamel paint it won't hurt the new type epoxy paints  it's like  water on the paint,lol years ago I would use brake fluid for a stripper on the old paint 
Life is short drink the good wine first

Offline Dave5Cs

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Re: strange turbo sound??
« Reply #13 on: April 09, 2019, 10:17:37 AM »

Acetone is nail polish remover...DO NOT use it on painted surfaces.
Otherwise, nothing works better.

No, Nail polish remover is Acetone with lemon, lol
"Perfect Frequency"1979 MCI MC5Cs 6V-71,644MT Allison.
2001 Jeep Cherokee Sport 60th Anniversary edition.
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Offline David Anderson

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Re: strange turbo sound??
« Reply #14 on: April 09, 2019, 02:55:05 PM »
Dropped off the turbine at M&D.  I took the cast iron elbow for him to clean.  He thinks it may be too pitted to use :o.  Not sure I agree, but we will see.

I got the bolt out of the turbo mount flange.  Took 3 hours.  All rethreaded and cleaned up for the rebuilt turbine.

My big problem is the 90 degree elbow with the flange.  Nobody has a 5 1/8" OD flange to fit a 5"OD pipe end.  It would have to be butt welded to the elbow.  I don't really like that.  Fleetpride had the ell and flange, but they are the same size.  I have been looking online with the same results. 
Anyone have any better ideas?   Kind of stuck right now.

David

 

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