T3/T4 rebuild, stumped

[trannybuster]

Well I got thing tore down, but honestly dont see a d#$# wrong with it...?..even the shaft play was very little..I lost the gear drive on the oil pump but really no gouging or very worn parts? The car would smoke after letting idle for long periods and was getting oil inside the IC piping which was causing high oil usage. Did a leak down test and got less than 5% across the board, I think three of them were nearly zero..?...any ideas?....no the oil return wasnt blocked btw, and my pcv appears to be good working order. Have a new kit coming for it anywho...I did see a small radius sized chip on cold side wheel, at the very outer edge OR it was from them balancing it, I did NOT do this damage( or grinding), it came from TU like this. I would guess the rubo has 10,000 miles on it, maybe less.

[turbovanman²]

So put it back together. If the turbine housing is dry, then the rings are valve seals are the issue. You can have good leakdown but bad oil rings. Look at the piston tops, if its clean at 12 and 6 oclock then its oil rings.

[trannybuster]

There is oil in the cold side ic piping, in fact where it makes a transition and two pipe sections connect via the boot it was pooled up, the inside of the intake has the wet sheen like it has had oil sprayed into it. I pulled the turbo without pulling the head, so a birds eye on the pistons would be....tough. FWIW the head was BRAND NEW when I sent it to TVALANT, it has new valves, seals etc about the same time the turbo went one, maybe little less as I did run a S60 for a few weeks and I would re-try the S60 but not an easy task with the hybrid header.
I still wont rule out the oil rings, I assumed leakdown doesnt mean oil rings arent bad, they are Wiesco pistons btw. It sure acted like bad turbo seals...it has the dynamic seal, what exactly makes them leak oil...?...would the seal 'rings' be gouged on the turbo or... ???...running down the road I can see any smoke unless I putting the boost to it or like I said idling long periods, like 5 mins or longer, hop in it and drive and it stops.

[turbovanman²]

Well oil in the piping is normal, mine always has oil in it. If the turbo was blown, then the turbine would be wet from oil under that tin cover, the turbine wheel and housing. If would be pretty obvious if it was the issue. I have read that some Wiseco rings had a heard time sealing properly from others on here so that could be the isssue. Oil rings can go back but you still have good compression and good leak down numbers. If you peak thru the spark plug holes, and move the pistons, you can get some light in there and see what the pistons look like.

[trannybuster]

Hmm..wouldnt bad oils rings suck! Probably why I have such good leakdown numbers! Will def. inspect them...thanks.

[trannybuster]

Yeah it def. looks like rings, the edge of the pistons are clean all the way around from sucking in those 8.00+ quarts of oil, and you can see the oil pooled next to the pistons. Good news is that I have a brand new set of JE's that use stock rings ready to put in! I think perhaps I will have the weisco's machined for stock rings as Ive never had an issue with the stockers.....weird becasue it acted just like bad turbo seals, like I said ti would even smoke when it sat and idled so any length of time. The turbo fins didnt have that much oil on them, the cold side was pretty dry really and the hot showed some leaking but very little.

[4 l-bodies]

FYI- I've had two freshly rebuilt turbos from a very well known Garrett authorized manufacturer/rebuilder leak a bit of oil into turbine housing. Of course in both instances it certainly wasn't the rebuilders fault (or so they claimed). After teardown and reassembly in both cases, the oil leaking/burning stopped immediately. Both times my longblock miraculously healed itself after turbo was re-installed (lol). I am hardly the only one to experience this. Probably doesn't take much out of tolerance to get dynamic piston and turbine piston to not seal correctly and cause oil control issues. I personally think they damaged piston on assembly myself and were too embarrassed or proud to admit it. Not saying this is the case with your turbo, but better check turbo carefully before just throwing it back on.
Todd

[trannybuster]

^^Oh yes without question, its getting rebuilt anyhow, Im not doing this twice. I did do some intense search/reading about turbo failures, oil usage etc....I have carbon buildup on the pistons but all along the edges say .250 from edge they are clean of carbon, the oil is being sucked in and cleaning them off. The turbo wheels didnt have that much on them.
I agree about rebuilt turbos, as I stated mine has a very small radius sized chip on the outer edge and I can say with good certanty it wasnt from my carelessness but good luck proving that one, it can be simply claimed something got sucked in struck the wheel.

[trannybuster]

The oil ring will slide into the block without even compressing it, very easily!

[trannybuster]

So some updates....my rings were shot on the Weisco's, due to poor cylinder prep, the oil rings would slide right in and the top compression ring had .030 gap! It acted just like a blown turbo, setting and idling it would start to smoke in a few minutes. The turbo looked great inside and the oil it was weeping was due to excessive blow-by, Im sure of it. Redid the hone, followed up with ultra finish hone, ground the rings(some low tension Weisco), put a new kit in turbo and so far no smoking and blowby is minimal. Will do leak down after about 1000miles. Also found why the car would just stall out then come back on..woot.

[zin]

I always like hear that the problem was found and resolved! What was the dying all about?

Mike

[trannybuster]

Stalling was from poorly crimped butt connector on main power feed (bang head)...I hope this caused the issue with the Moates..cross fingers! I try to leave feedback, someone has to find it useful.

[Vigo]

Glad to hear you found your issue.

I had one stock t3 turbo leak oil out the intake and not the exhaust. It seems everyone talks about exhaust side leaks and in your case it turned out not to be the turbo anyway, but i have seen one of my turbos leak oil on the intake side. It wasnt obvious in the compressor housing but i figured it out by taking off the intake and charge pipes and revving the engine, a fine oil mist would gradually collect on my hand if i held it in front of the outlet.

[trannybuster]

^^This was my first turbo rebuild...in no way was I going to spend 300+ on a rebuild especially since this one had MAYBE 5-8000 miles on it. Ive read that too much restriction on the intake side can cause cold side leaking, but I guess with the filter and piping off this certainly was not your case..lol... I also added a 20 micron (.0007in)filter in front of the turbo.....the one TU and FWDP sells is like 70 microns or 0.002in, the filter I added is a standard spin filter (Amsoil EA 15,000 miles). Oil cleanliness can be directly linked to engine wear...just pointing out the obvious.

[turbovanman²]

Sucks it was the rings but the clean edges proved it.