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hey guys,

my bros tx3 turbo laser is blowing a sh!t load of smoke, after accelerting.

it idles fines, hits boost fines, and doesnt smoke untill after i let go of the accelerator. once you let go, it blows smoke like there no toomorw, fill thwe whole street up etc etc.

it was the first drive after a top end rebuild. e.g new gaskets and seals(including head gasket), shaved head etc etc

the psitons looked fine at the time too.

after the lap around the block i found there was mayo under the oil cap inicating that oil and coolant had mixed.

is the block/head screwed, or did I just stuff the rebuild??

why would it smoke after hitting boost? pcv valve? turbo seals?

thanks

steve

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well the smoke was white/grey color.

the creme shit under the cap means the oil/coolant are mixing, which usually means a blown head gasket.

thing is, the head gasket is new, and head has been shaved, so either I reassemble it wrong, or the block is stuffed.

i only hit boost a couple of times, and i didnt take it redline, plus i let it idle and warm up for a while.

ill see what happens tonight.

steve

Smoke on decelleration usually means a couple of things.

1) faulty valve stem seals. I assume you changed them so it could be they were the wrong ones.

2) Turbo seals possibly?

What was the reason for the rebuild?

If it was for a blown head gasket maybe the creamy residue is a result of that initial problem. If it showed up just after a run around the block the oil itself on the dipstick would be white too. If not should be OK in that regard.

I'm no mechanic but I would get a mech to test for hydro carbons in the radiator before ripping things apart.

the rebuild was to freshen up the engine. the guy i bought it off (friend) claims there wasnt any problems with it before hand.

the stem seals are brand new.

one thing that might cause the smoke is the pcv valve. might be stuck open.

the water/coolant mix is a differant problem.

steve

If the symptoms have happened all of a sudden my moneys on a Cracked / broken piston ring land......

its happened to me a few times now :O

On both occassions Pistons appear to be fine even when removed from the Block at first glance, but with a bit of fiddling you can remove the piece of piston between the rings themselves, generally under boost they are compressed and oil does not seep thru hence no smoke under load, however once you let off you leave a nice stream of smoke behind you! its normally caused by Detonation, lean out and can happen extremely quickly ;)

Is you intake system full of oil also?, or your catch can (if Fitted) filling with oil?.

Maybe your car since rebuild has got hot, maybe within one cylinder, blown the gasket, and cracked a piston....?

Leak down test best way to check for Piston ring land.

found th problem, it was a pcv valve stuck open!!

basicly it was pressurising the whole oil system while on boost, then once the throttle was let off it would blow all the oil in the rocker cover in the intake.

i just stuck on a oil catch can and it fixed the broplem.

the oil under the cap only apperaed once, i think the was some condenstion in the engine or something.

its all ok now

steve

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