8v92 turbo question

[Blacksheep]

This week while removing the turbo from my 8v92 to fix an oil leak at the base, the mechanic accidently chipped a very very small tip off one of the turbo fins. Exact size, I'm not sure but it is really small, maybe less than 1/8 inch. He say's it won't hurt and the really old mechanic says the same thing. My mechanic was worried about it maybe being out of balance until the older mechanic gave his opinion.
I don't know that much about them so I'm asking you guys! What do you think?
Oh and the turbo is all back together and installed as of today.

The new fuel lines have been installed and tomorrow the ecm goes back in. He also found that somewhere along it's life that the power harness to the ecm was replaced because the old one was still there laying on top of the motor.  That's gone now and everything is now in split loom and attached for minimum movement. He also found my jake problem and with the help of a schematic, it too is now wired. Won't know for sure if they work until the ecm is back in!

If all goes good, it should be running by Friday. Then the new air bag, oil change, lube, and brake check!

Ace

[VanTare]

ACE if it is on the compressor wheel side make them replace it   

David

[Blacksheep]

oh yea, I forgot to mention which side it was on. To my understanding there are two sides. One from the fresh air and one from the exhaust ( I think)! The chipped fin is on the fresh air side and it is VERY VERY small! I'm just not sure if it will hurt! To me, it odesn't look like it will but I don't know how touchy those things really are!

Ace

[Jriddle]

The Turbo spins at a very fast RPM. It is hard to tell how big a very small chip is. I would have it replaced if it were mine. If the shop isn't worried then I would get that in writing. Some sort of warranty would be in order in my mind. What I would worry about is if there is hair line cracks that you can't see. I would hate to see you shell out your turbo and have to find all the parts in places that may require a top end tare down. I sometimes over look things because of my big heart, but would stand my ground on a replacement turbo if I thought they did the damage.

John

[RJ]

Ace -

Turbos can spin upwards of 100,000 rpm, so even a slight imbalance on either side of the shaft can wreak havoc with the bearing it rides in.

You'll know the bearing's gone bad because your oil consumption will go up and you'll start seeing more blue smoke in the exhaust, as they usually fail on that side.

My experience with Corvair turbos was such that usually the bearing failed first, then the exhaust turbine, and lastly the compressor fan.

Personally, I never had a compressor fan fail and spit it's blades into the intake system, but did have a turbine disintegrate - went from 180 hp to 80 hp real quick!

I agree with John, tho - get it in writing that they chipped the compressor wheel during reassembly, and any subsequent repairs required due to turbo failure they will cover.  If they won't put it in writing, maybe have your attorney give the shop owner a friendly call. . . and keep note of this thread's topic/number, so it can be used as back-up if you get into a "situation".

FWIW & HTH. . .

[Kenny]

Ace, absolutly replace it. With the turbo spinning at potentially 100,00 rpm, balance is critical. With the turbo being such small rotating mass to start with, even a small missing piece will cause an imbalance. Also how did it get broken? Was it dropped or what. It took some force to break it and there may be other damage that you dont see in the form of bent turbine blades that also cause imbalance. We design and build turbo testers and balance is one of the most critical parts of a turbo. An imbalance can cause vibrations, premature bearing failure and in some cases total destruction including flying parts into the intake manfold. There is no doubt in my mind to replace at any cost.
Kenny

[mikelutestanski]

Hello:
   Ace   If you want a professionals opinion  google evergreen turbo. He is in Ocala fl  and does work on all kinds of turbos; Its Charles Brown at evergreenturbo.com   1800 2752531.
    I believe that the other comments are correct and the turbo should be replaced. The unit spins so fast that imbalance could be a problem. 
   However the turbo guy can help you out.. You can probably ship it to him and he will beat most prices. 
   When I did the turbo on the L10 the exchange price was $ 950 dollars from Cummins and a local parts place.He rebuilt mine for $350.
    I am not pushing this guy but he has done right by me and he seems to know his stuff..   
      Regards and Happy bussin   mike

[Hartley]

Ace,

Replace the Turbo.. No question on that.

Typically once a turbo fin is chipped or damaged, It will continue to fracture
and self destruct sooner or later. The last thing you need after all the problems is
a turbo fragging out and sending particles of hardened metals into the blower and into the engine.

If you decide to leave it alone, You might as well start shopping for a new engine now and saving up the money to have it changed.

Ask any A&P Mechanic about turbine failures....

Dave..

[Van]

Ace ,I gotta agree with the Doc,we had a private plane come down in N.las vegas because of a faulty turbo.Change it now while the opportunity presents it's self.My ? is how did they chip the blade and did they retrieve the broken piece? Good luck.Van

[skipn]

 If he stuck a pry bar in the end so as to pop it loose on the
exhaust gasket..........get a new mechanic

Skip

Edited after Aces further details........
    Yep an honest oops do happen.   You may now have a turbo that
when it spins up will have a whistle.......hopefully it will be at a pitch
that only dogs and deer can hear 

[Blacksheep]

Ok I made mention to the shop owner who DID know about it and after I expressed my concern/s, he said he would look into a little deeper!
The way it got chipped was when he was removing the cover (by hand) it was stuck and when it surprisingly let go, he jerked and went back against and that is when it got chipped. It was definitely an accident! I was there and saw it happen. I don't blame the guy doing it. It could have happened to anyone! The shop said they would make it good IF anything was to happen but that is when it happens!
I will get that in writing at the pay up time for sure!

Ace

[Lin]

Ace,

If the turbo fails on the road, their warranty may be worthless or costly to use.  I would think that it is just plain good business on their part to avoid having such a liability on your engine's future.  It may be better for you to insist that it be repaired now.  If they can make a good case that it should not be entirely their expense, it still may be worth it for you to pay a fair amount toward it.  Any future failure could to cost you much more than preventing it, not to mention lost vacation, lost income, lodging, etc.

[busshawg]

I'm with Lin, replace it, even if you feel that you may need to eat some of the expense. You are in the right position to get a half decent deal on a turbo and it is warrented! The last thing you want is to be sitting on the side of the road a year from now because you've been running it with an unbalanced turbo. It will probably be fine for a while but when it does go what kind of an aguement are you going to have with your shop that to me me sounds like a decent place so far. I'll garrentee you they'll tell you it was a used turbo when it was dropped and in a good case senario won't pay for the whole thing anyway, never mind all the labour that you may have, ecspecially if you have to tare your motor down. You don't want one then coming apart at all, never mind climbing a hill. I wouldn't worry about anything in writing, with some of my experiences that's not worth a hill of beans, too many variables, replace it. My .02 worth.

Grant

[PP]

Ace,
Everyone realizes how difficult it can be to insist on fairness when you know the damage wasn't intentional, but right now, while they still have the bus at their shop, it might be a good idea to negotiate a fair arrangement and keep both parties happy, especially if you like their work. Maybe they will do the labor and share the cost of rebuilding the turbo. You get a fresh turbo at a discount and they don't have to eat the entire thing. Just my $.02 worth.
Good luck and hope it works out for you,
Will

[kyle4501]

Tough break . . . . If it were me, I'd replace the turbo.

Here is why:
If it was hit hard enough to chip the impeller, the bearing took a hard hit also. The turbo impellers must be made of high strength metal to withstand the stresses from spinning so fast. Along with the high strength comes brittleness which means even if there are no other cracks in it now, the imbalance can cause some to develop later.

You might think that 0.001 lb isn't much, but at a radius of 2 inches at 100,000 rpm it is the same as ~550 lbs.
Still think it doesn't matter? Even if the impeller doesn't fail, the extra load on the bearings isn't going improve their lifespan.

What happens if the blade disintegrates while at speed on the road? The pieces will go thru the blower & into the cylinders on their way out of the engine.

Only you can decide if that a risk you want to take.


I'd think the shop should eat the labor & cover some of the part cost because they are paid professionals & should be responsible for damages they induce. The fact that it was used when you drove it in is pertinent only in your choice to help pay for the replacement turbo. Their actions are what caused the turbo to need replacement now rather than later.



What would your customer expect of you it you stained the carpet in their house while installing flooring?