How hard is a turbo rebuild

[subway]

I picked up a what i think is a factory turbo from a 94 IDI. it is a Garret wast gated unit and feels solid as far as shaft play. trouble i see is it has some nicks in the compressor wheel. i haven't got the other side off to see how the exhaust side looks. three of the bolts broke loose one skipped when i put a wrench on it and i am afraid to push the other two much more until i can get some heat or something to it. don't know how many miles are one the thing either.

so i guess how hard is it to go through one of these guys right? i have successfully rebuilt several engines before so it cant be more complex than that. i saw one taken apart at the rally and know basically how they work but have never tinkered with one before. i really hate to put money into it and have it spin apart but i am not afraid to try it.

anyone know any good manuals that can give me breakdowns and measurements of all the stuff? i have access to micrometers, bore gages, dial indicators and good stuff like that.

thanks

 

[6 Nebraska IDIs]

Russ is invaluable when it comes to rebuilding a turbo. I called him two or three times during my turbo rebuild, and he always has an answer.
Most guys would say to run that turbo the way it is if it doesnt have shaft play. I've seen much worse in terms of compressor wheels.

 

[RLDSL]

The guy on ebay that sells rebuild kits for around $75 will balance your assembly free when you buy one of his kits. I did that and my compressor side wheel was shot and he had a new one for only around $85, , I still came out cash way ahead . THe thing works great

Here's a nutshell version of rebuilding one. A few steps missing like replacing the rings, but it's enough to give you an idea of what you're in for.

Unfortunately, there is close to zilch on the net on turbo rebuilding, luckily, it's not that hard

 

[JwS]

I got my kit from the guy mentioned above, nice guy to talk to and gave me a good deal because I didn't need it shipped (I live like 15 miles away). Everything I have heard online about shipping etc was good.
JwS

 

[typ4]

I would make sure the wheel doesnt touch with a little side pressure and give it a try, if it was out of balance the bushings would be toast. If you want it like new then order a new wheel and rebuild it. I think the last kit I sold was a major with bolts and plates, good bushings not the imported junk and it was about 65.00 plus shipping. New wheel is about 150.00

 

[subway]

maybe i will give it a shot then, does anyone know a runout spec for side play and such to give me a better warm a fuzzy feeling than "it feels tight".

i just figured not knowing the history it might be better to tackle it now while it is sitting on my bench.

i forgot to mention, not sure if this makes a big differance but we got the truck because the engine was blown. guy threw a rod through the block taking it to the dealership so i dont know if the turbo could have possibly been part of that problem.......

thanks for the links RSDL that helps

 

[Agnem]

Consider this... some folks have been known to intentionally nick their compressor wheel to get more whistle. It's a fact.

 

[typ4]

It more than likely broke a valve spring and dropped a valve, these things dont throw rods unless ran out of oil or hydrauliced due to cavitation or head gasket leaking.
I have the shaft and housing specs at work I can post thenm later tonight or search on here they have been posted before.
With the factory clearances and new parts you woild be amazed at the side play 40 to 50 thou is not uncommon, the shop I buy parts from says as long as the wheels dont touch the housing and it isnt leaking ,use it.. Oh btw ,oil takes up about 4 thou space. Squirt some in there and then check.

 

[RLDSL]

Consider this... some folks have been known to intentionally nick their compressor wheel to get more whistle. It's a fact.

You've got to be kidding
I bet that was the kid with 4 playing cards clothespinned to the rear tire of his bike all grown up

 

[FordGuy100]

Yeah, they actually do that. I've only heard of ricers doing that though . I forget what its called though.

 

[subway]

http://cgi.ebay.com/ebaymotors/Fake...318QQhashZitem220262649004QQitemZ220262649004


how about this

thanks Russ that would be great if you could, i guess it wouldent hurt to pull the motor apart just to see. its hanging from the picker with air tools next to it.

 

[6 Nebraska IDIs]

I believe its called "Clipping" the blades Justin. Guys in the import world have it done all the time. They claim it reduces spool time and boost lag, but I personally dont see it having that affect. Just adding wear to the compressor wheel before its even there if you ask me.

 

[subway]

well measured it last night and got about .0003-.0004 axial play and around .0045-.0050 radial play. i didnt add any oil to it either it was just what it had from sitting. i actaully had to move it and the radial play increased a couple thousands as i worked it like i was displacing the oil and stopped at the measurement i got. i thought the numbers looked good so i quit.

should i be concerned about a small puddle of oil on the out side of the compressor snail? there was a small amount that looked like it leaked out from the inside of the turbo. could it be from sitting in a funny position with no oil pressure on it or should i just replace the seals?
thanks

 

[Agnem]

The turbo I put on Lady Moose looked for sure like the seal on the exhaust side was no good. Hypermax told me those seals only really seal when its running, so if you have it off the truck and tip it around it may leak like the devil. I took their advice, and have not had a problem.

 

[RLDSL]

I've run across basicaly the same info Mel has on those seals in other places. Essentially , those ring seals are for holding in gas pressure, not oil so much. If you look at the design of the things inside the bearings are pretty tight and once the oil finds it's way past the bearings, there is a rather large resivior area on each side to collect the oil where it won't build up pressure against the seals at all, and the oil return path to the crankcase is all free flowing drainage.

To have excess oil finding it's way past the rings ( providing a ring isn't simply broken )is more of a symptom of bad bearings allowing too much sloshing around, otherwise, it should just spin off into the side chambers and drain out with just enough oil getting on those rings to keep them happy

I bought a couple of extra rings to play with ( after screwing one up and I noticed that even when the things are fully seated, there is quite an end gap on them, so like the Hypermax guy was saying, the turning speed must have a whole lot to do with sealing .