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Long story as short as I can phrase it.
740 turbo 140K pampered life - bought it for my son.
Driven last bitter winter with a 5W-30 and at 1500 miles I drive it and the oil light comes on, very briefly, x 2, before I pull over at autopart store and add 2 quarts. My son denies the light prior.
2 months later I'm driving it again and notice it's spewing smoke and I think I hear the Turbo ringing. In a panic I park it and begin the disassembly.
There is very light scoring in the compressor housing but the fan is good. Half of one of the journal bearings is severely worn. Dremel to grind some carbon on exhaust side. I put a kit into the turbo and reassemble.
I start it...after 30 seconds it starts to smoke...I continue to drive and once hot it no longer smokes at all. I periodically drive it this way to exercise the vehicle while trying to figure out what to do.
So in 1000 miles there's misted oil about the turbo. I'm thinking it's from the turbo blow off valve spewing oily charge when I get off the accelerator. Or is it pushing from the oil filler cap gasket given that there's positive blow by-detailed below. There's oil in the Hoses so that they drip on disassembly, even on 'cool side' of the intercooler. But there's no drip of oil at the port where the pcv enters the intake between the AirMassMeter and the turbo intake.
All the PCV apparatus including the oil separator is only 20K old. Blow by is fairly strong with a positive pressure at the filler cap. Dry Compression Test is 160,170,145,160. Wet Compression on cylinder 3 (145) raises it to 155. No Leak down done.
The tips of the plugs are all clean; There's oil on the threads of plug #2 (had highest compression, 170)
So...has anyone had a turbo blow oil after a rebuild kit?
Has anyone had a burning oil issue that goes away after the engine comes up to temperature?
Has anyone lived happily with compression numbers like these?
Has anyone had oil wet threads on a single plug that wasn't fouled?
Can high crankcase pressure alone explain the burning oil AND the oil in the intercooler hoses?
Analyzer
90 744T
97 850R
03 V70
Retired 244, 245, 965, V90
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