Turbo Failure

blacksix

Member
Joined
May 15, 2002
So I recently had my TE61 rebuilt by a reputable local turbo shop, seal was leaking. Shaft play wasn't bad. Engine ran fine although smoked at idle from the turbo seal. After they had rebuilt it they showed me where something had gone thru the wheel (put in a new one) and advised I check out the engine.

A couple of years ago I blew a headgasket between cylinders so I surmised that it was HG parts that did it. Same time I pushed out all the coolant and cooked the engine pretty good. Having a new family and a minimal budget, I changed the HG, flushed the oil a couple of times, and then ran the wheels off it some more. Ran another few thousand miles and 3 years since and never ran better or faster (11.40's), although cold compression was down. so I'm pretty sure the rings are baked. Every oil change there was dust on the magnet, but never shavings or anything. Oh, well, she still runs, I thought.

Back to the present. Checked compression - - same as before, 100 psi dry, 125-130 wet (204/214 cam.) Dropped the oil, looked same as usual. I assumed the debris had been that old HG so I bolted it all up and ran it. Winter conditions, around 40 degF, so I took it real easy. Got on it a couple of times out on the dry freeway and the turbo sounded like a cheap vacuum cleaner right off the bat. After a couple of mid-throttle 15 psi pulls I started to hear a scraping noise under any boost at all so I just babied it home.

Pulled the intake hose and the turbo is toast, probably about 20 miles on it. Shaft is all over the place and seal is leaking. Pulled the oil feed line off to check for pressure - - I ran some oil into a plastic dish and found it hazed with brass. Pulled the pan and found more brass dust there, with slightly bigger flakes on the bottom. Pulled the bearings and they look OK considering - - no real evidence of grinding debris, just worn silver and the mains are a little beat from detonation (some copper showing.) Cylinders look a little scored but about what I would expect. So 2 questions:

1) Is there any chance the turbo rebuild is at fault here? Ran fine before, wouldn't have touched it if it wasn't smoking. No odd noises, boost was smooth and solid. Is there anything that can go wrong in a turbo rebuild?

2) I was thinking of swapping out the crank bearings and running it. The engine is what it is - - rough - - I'm working on a roadrace car and really don't want to pull & rebuild the Buick motor at this time (trans is also almost due) if it will get me through weekend cruising for another couple of years. However, I don't want to scrap another $700 turbo trying it out. Is there enough brass floating around the motor/oil cooler to ruin my day again?

Should I bother to get an oil analysis done? Thoughts & opinions? Also posted in the Turbo section.
 
Update: spun a new set of bearings into her and installed a Turbo Saver filter system. Turbo builder rebuilt it again (under warranty) but advised me they thought it was overspeeding due to a rich mixture" or something, judging by the black burn marks around the bushings. Told him I didn't think so, all the plugs were perfect.

Fired it up for 2 minutes, then drained the oil and changed the filter. Road tested it (another 20 miles), spun the 2nd filter off and dumped it out to find it LOADED with brass again. WTF? Pulled the intake pipe off to check the turbo and this time it's fine, turbo saver so far seems to have done its job.

So where is all the brass dust coming from?

:(:(:(
 
Try to be in a state of mind where you can be patient with the situation and meticulously check things.

Sources of brass include main bearings (don't forget the thrust surface), rod bearings, cam sensor bushings, cam bushings (unlikely?), and I think the bushing in the turbo.

I've read that some people have had trouble with certain torque converters causing the thrust bearing to be eaten up.

Are you certain that most of the brass was out of the engine from the previous time before running it this time?

Sorry for not addressing all of your questions.
 
Having replaced the main and rod bearings, my engine builder agreed that they did not show excessive wear or signs of grinding metal. Thrust surface was OK I think but I'll double check. Turbo end play seems to be as new. Cam sensor bushings - - didn't check them when I pulled it out to prime, I guess I could.

What cam bushings? You mean the bearings?
 
If you had metal circulating through the engine you will have repeated failures. The turbo failure likely started off as thrust failure from contaminated oil also. Once the thrust failed the turbine was allowed to thrust back and forth and it gets ugly from there. The only fix is to have it torn down and everything measured and cleaned 100% and reassembled and everything documented. If all the passages werent properly cleaned then the debris will continuously free up and circulate and you will have repeated failure.
 
I had a customer who tried a local builder attempt to rebuild a TE44 and it was a disaster, 3 tries they rebuilt it over
2 months, each time we had to flush the engine. the last time it happened and we had to put my loaner stock turbo back on they gave us more money than we initially paid to cover the intake cover they destroyed and another engine flush.
We ended up with a used Turbo a bit bigger than the TE44 and he never looked back.
The turbo sounded like crap while in boost. I am fairly certain they were having issues with the Balance, or they could have installed the wrong turbine and were overspeeding the charger also.. who knows.
You'd think a turbo shop would pay attention to what wheels were on it when they got it...
 
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