Turbo oil pressure

[1turbo6]

is it possible to have to much oil pressure? my car since the engine rebuild runs about 25psi hot and 60psi cruising. I had my te 44 rebuilt in may due to smoking. Last night I went to track and on the first pass at about 1/8 mile the car popped (no knock) and started smoking like crazy, I shut it down and got the up pipe off and it was coated in oil and sounded awful (like turbo wheel damage), I think the pop was the oil seals blowing out. I am running a turbo saver and was told by precision that it is not possible to have too much oil pressure on a journal bearing turbo. but what caused the thing to grenade??

 

[GNVYUS 1]

I have no idea why Precision would say you can't put too much oil pressure to a journal bearing since they used to sell a -6 feedline with the Turbo Saver and it would smoke like hell.

You seem to have a tad higher pressure than most, I'm going to a -3 feedline with 1/8th npt 90 degree fittings on my Turbo Saver due to a slight smoking problem also.

Corky Bell clearly states a journal bearing turbo needs no more than 35psi, well we're all beyond that one and a -6 and -4 are bigger than needed. I've been running a -3 for years on my PTE in my Talon and it doesn't smoke like the GN does at times.

We need more data on your popping, I had a few intake backfires at the track due to the crappy Walbro being 8psi off at WOT so we need more info. I don't think the turbo could do that unless you're eating a ton of oil maybe.

 

[1turbo6]

Went to remove the maf pipe and it was already 90% off, I guess that was the pop. the compressor side wheel shows signs of rubbing and there is considerable up and down shaft play. not sure what the warranty is on precisions rebuild, but well see and this time I think I'll add one of these.


Oil Inlet Restrictor - .065" hole size 1/8" NPT (for Journal bearing and larger GT BB): atpturbo.com

 

[GNVYUS 1]

That is tiny since it's the last hole before the turbo shaft, .065 is for BB turbo's IMO. The -3 is a .125 with the -4 being around .225, I'm all for sending less oil to the turbo but that size seems too small even for me. :wink:

 

[1turbo6]

talked with precision today they feel 60 psi is not too much pressure and want to see the turbo. I removed the turbo after work and the exhaust side is totally destroyed!! the shaft actually snapped in half. I guess that was the noise I heard,has anyone ever seen this happen?? I cannot believe it broke. what in the Hell could have caused this??

 

[RUQWKNF]

I can tell you, one of two things happened. Either particles in the oil contaminated the rotating assembly, leading to castostrophic bearing shaft failure due to premature wear on the shaft and bearings, or there was a failure with an internal component. Either way, the guys at Precision will be able to determine what happened when they do their tear down inspection. Just be patient with them, as repairs can typically take a week to 3 weeks depending on how backed up they are.

The pop you heard was undoubtly the sound caused by the shaft breaking and blowing the boost pressure back through the MAF pipe. This would also explain why the MAF pipe was blown loose. Big pressure spike when it let go.

When you said earlier 60psi while cruising, was this no load steady rpm cruising? Do you know what your WOT oil pressure was?
60psi while cruising down the road is slightly high IMHO. Just curious if you know what the oil pressure was at wide open throttle?
Precision should be able to take care of you.

Patrick

 

[1turbo6]

I have been running a turbo saver since the rebuild in may,so not sure about contaminents but they said prior to the rebuild there was journal damage. I have never really noticed the oil pressure up over 60 psi, but I think I am going to change the spring in the oil pump to a lighter one. I have been noticing smoke for the last few weeks but chalked it up to the umbrella style valve stem seals the engine builder used. I guess it may have been the turbo all along. I agree about the pressure spike popping off the maf it makes good sense. I am not in a hurry to get it back as I was planning to pull it off the road for winter the end of the month.

 

[Pronto]

Maybe the prior journal damage weakened the shaft and it was just a matter of time before the shaft broke.

 

[1turbo6]

anything is possible, I have to get shipped out this week.