As soon as I quit smoking my bus started, lol, after the doctor released me from the cardiac unit I ran like a scared puppy to get as far away as I could, on the way to ohio I busted one of the clamps on my turbo on the hot side, I doctored up a temporary fix with a coat hanger and got it as tight as I could cause it was a weekend and no place open to get a new clamp at. I endured the lack of power and black smoke and when we got to columbus, I replaced the clamp but the black smoke continued, I'm sure it's unburned fuel so I checked my air cleaner at the suggestion of a couple of friends here and replaced it, no change, still fogging mosquitos and lack of power. Possible solutions I've heard so far is a turbo gone south, an exhaust gasket leak, a plugged catalytic converter, it all started with the clamp breaking , need idea's, the motor is a 6V92 with an allison 740. One more thing is my turbo boost is low, I haven't been able to get it over about 4 pounds since the problem started.
Quote from: cody on August 12, 2008, 09:00:21 AM
As soon as I quit smoking my bus started, lol, after the doctor released me from the cardiac unit I ran like a scared puppy to get as far away as I could, on the way to ohio I busted one of the clamps on my turbo on the hot side, I doctored up a temporary fix with a coat hanger and got it as tight as I could cause it was a weekend and no place open to get a new clamp at. I endured the lack of power and black smoke and when we got to columbus, I replaced the clamp but the black smoke continued, I'm sure it's unburned fuel so I checked my air cleaner at the suggestion of a couple of friends here and replaced it, no change, still fogging mosquitos and lack of power. Possible solutions I've heard so far is a turbo gone south, an exhaust gasket leak, a plugged catalytic converter, it all started with the clamp breaking , need idea's, the motor is a 6V92 with an allison 740.
Have ya checked the timing at the distributor? Or maybe the choke on the carburetor is stuck on! ;D BK ;D
If I have to crawl in to check the distributor I may as well put in new spark plugs too, right? lol
cody, you missed a good show. Daly and Vincent were excellent. but i guess now i know why.
glad you are at least up and around, although sorry for the black smoke issue.
obviously, i'm not the mechanic, but if the turbo came loose, why would anything else change. and now the turbo is fixed, but still 4#'s only.
remember, we're just off the i80/90 by cleveland west if you move this direction
Quote from: cody on August 12, 2008, 09:14:22 AM
If I have to crawl in to check the distributor I may as well put in new spark plugs too, right? lol
It's up to you, but if ya do just use the stock ones. Those platnum, and split fires are not worth the extra $!
;D BK ;
Seriously Cody what kinda boost are ya showing now days? Hmmm still has me puzzled. Or is that bamboozaled? Shoot I dunno! It is smoking hard or thick all the time or just on take off? Are ya sure it ain't Libby in the back blowing smoke out the window? Just curious. ;D BK ;D
The guage shows about 4 pounds boost at the most under hard load like on a hill, the smoke is black and mainly on take off from a stop or climbing a hill, on just an easy cruise on level ground the smoke is barely noticeable from my seat. The power is so lacking I can barely get up to speed from an onramp and hills that never bothered me before are a crawl up now. The clamp that broke was the one on the hotside between the exhaust part of the turbo and intake turbo, the flanges are in good shape, when it broke it sent a lot of black soot all over the back of the engine area. when I replaced the air filter the filter showed a lot of soot inside the pleats but the engine side was clean so it stopped the soot at that point. after replacing the clamp I don't see any exhaust leaks, not saying they arn't there, I jsut don't see any now.
Well I'm afraid to say it, but it does sound as if the turbo maybe ailing. Hard to diagnos over the keyboard, but the indications are there! Might check around and see if there are any old timers who are familar with 2 strokes in yer neck of the woods. It'd be advised to get a first hand knowledgable opinion before replacing expensive parts! FWIW ;D BK ;D
Quote from: Busted Knuckle on August 12, 2008, 09:46:13 AM
It'd be advised to get a first hand knowledgable opinion before replacing expensive parts! FWIW ;D BK ;D
Now on the other hand Robert thinks the turbo on 727 (the bus we boought for him to drive) is week. (he just won't admit that it ain't the powerhouse the new bus is. And wants me & my $ to make it one! LOL) He wants me to check on replacing it with a performance turbo like I did on my bus. I guess if we did that I could send ya his old one, it might get ya by, until ya get down here this fall! Or atleast we'd know Robert was right and it's bad too! LOL! ;D BK ;D
You know me always willing to help! LOL!
Would the one from 727 fit my bus? Only number I can find on mine is 'M 84 AR.75 Garrett" on the cold side, I can't find any numbers at all that are readable on the hot side, too much scale and rust to read anything on that side.
Cody I think that at this point you might want to inspect the rotating assy for accelerated wear. It's tough to inspect the turbine side blades. However, it sounds like a combination of compressor wheel damage or turbine wheel damage.
If you haven't ingested anything, then you have bearing wheel that is leading to wheel rub. The rotating assy is running off center and is acting like a lathe grinding your blades on the housings. Oil is breaching both the turbine and compressor side seals.
I'm not sure but it's possible, they are both 6V92's. I'll check that Garret # out in a bit. I have to run to town real quick. I'll get back to ya on it! By the way that should be a good # if ya want to google it and see what ya find it crosses to in the mean time while I'm gone. ;D BK ;D
Cody you should have a TV7511 turbo and the a/r should be 0.96 to 1.23 depending on the injectors fwiw pull the intake side and pushing in and turning check to see if it draging but it sounds to me like you have a leak
mine says the a/r is .75, no sign of any dragging or bearing problems at all, a leak is probable, just can't find it
Cody;
You have a turbo problem, You may not have the 7511 turbo depending on the year of the engine.If you don't put one on and depending on the injectors use either a .96 hot housing.or 1.08
Don
Sounds like I'm in for an enjoyable time, I'll pull the valve cover and see what size injectors I have so I'll know what a/r I'll need, I'm thinking I was told the injectors were 65's but Im not sure of it. The bus is a 1981 model10.
Cody,
Have you checked for any leaks on the "cold" side of the turbo? Even if turbo is compressing, if the pressure is leaking, you would not get much boost. Jack
Thanks Cody I thought it was 1985 model the coach engine for 1981 had a TV7101 and do as Don suggests the TV7511 will work better for you
Cody,
Can you get in there to pull the whole turbo? I think there are 2 clamps, 4 bolts and an oil line, (typical setup). Then you can probably get more information from it.
You've been given some good information here, I would go with checking out the turbo for rubbing and damage. It does sound like you got a piece of debris in there and damaged the impellars and /or the bearing and seal.
From what I remember of looking at your engine last year, removing the turbo is going to be the easiest way to do any checking.
The other thing I would be concerned about is that silly cat converter. It's possible that when you lost the clamp, enough soot was forced down the line to plug it. This would cause excessive EGT, back pressure and loe power, not letting the turbo spin up to full power and thus causing excessive fuel with not enough air.
Good Luck,
Dallas
I think we can safely rule out a plugged cat converter, I just shined a flashlight into it and there is nothing there lol, the cat converter is about 18 inches long, I can see clear into the muffler from the bumper lol.
Cody: 1 thing I found out the hard way if going to buy parts for that engine from a DD dealer know what to ask for because when they run the serial number you get parts for the engine when it came from Detroit Diesel new
Cody,
Are you still in Ohio? I am on the West Virginia border on I-70. Maybe I could help.
Josh
We're back in northern Michigan now.
Okay, I am glad you are home safe. If you are ever over her and run into trouble, email me and I will do all I can.
Quote from: JackConrad on August 12, 2008, 11:03:10 AM
Cody,
Have you checked for any leaks on the "cold" side of the turbo? Even if turbo is compressing, if the pressure is leaking, you would not get much boost. Jack
Cody Jack is very right here. As well as all the others. But if you'll recall during my recent TURBO dilemma, even after putting on a new high performance turbo it still sucked! (Literally) Partly because the air filter was plugged from excessive oil and etc. And because it was sucking/blowing the hoses off! Once corrected it runs like a scalded
greyhound um dawg! Better than it ever has since we've owned it!
Don is by far the man to answer the best performing turbo # for your application.
I had a Detroit Dealer tell me, the turbo we put on was the wrong one. (we bought a Borg Warner higher performance instead of the stock Garret) But when I questioned them about it and was fixing to call "Diesel Power" in Paducah where I bought ours, they quickly changed their mind that it was indeed an "ok" replacement for the stock one.
I'll see what it is #727 has on it as I'm leaning toward a Borg Warner replacement on it also! ;D BK ;D
These guys are about the best in the biz http://www.blaylock-turbo.com/
I'm a big fan of keep it simple.
I'm with Jack. You'd best be absolutely, positively sure that all your pipes/clamps, exhaust and fresh sides, are all sound and your turbo pressure, hot or cold, isn't pissing overboard.
You were fine before the pipes came apart...the pipes came apart, and never right since.... I'd still blame the pipes before more complicated things.
happy coaching!
buswarrior
You may have carboned up the turbo to the point that it just doesn't want to spin up anymore. Without boost, you get black smoke and no power. Need to replace the turbo. Good Luck, TomC
Ahh, maybe I'm a little late to this, but have you opened up the compressor side and hand turned the wheel. Should turn free, with a (very) small bit of axial play.
I guess the turbo could have swallowed something when the clamp broke but I'm with Buswarrior. If it was working fine before that then I'd suspect a leak until somebody convinces me otherwise.