White smoke from GTR -- HELP!!

[Amaru]

Hi all,

I have an R32 GTR which just had the engine rebuilt 2500kms ago. Its running HKS GT2530's which are also 2500kms old and a Power FC.

The car was running beautifully on and off boost (didnt hit above 0.2 bar boost for first 1000km's, not above 0.5 bar till 2000kms, now hitting 0.8 bar). The car is running way to rich and is being tuned in the very near future.

A problem has come up though, when coming onto boost the car gives a quick puff of white smoke, then goes brown/black as its overfuelling. I took the car back to the engine rebuilders, and he suggested its fuel vapourising in the exhaust from how rich its running, and although rare, he has seen it happen before. What are other peoples take on this?

I know constant white smoke is head gasket failure/cracked head/stuffed turbo, but this just makes a small puff as its coming onto boost and then it doesnt happen again.

Any ideas??

[benjiman74]

as the motor is fresh the oil rings would not have bed in properly yet. when coming on boost you will be evidencing the blow by if you still have your breather hooked up to the pcv valve. the dark smoke thereafter will be fuel if the mixtures are set rich. hope this helps.

[Amaru]

It has only started happening in the past few days. The mechanic mentioned he might need to run an oil catch can, which I was going to do anyway, then checked the pcv breather pipes and intake pipes, and theres next to no oil in there. I would have thought after 2500kms the oil rings would have bedded properly?

[benjiman74]

if the oil is breathing through the pcv then you wont find oil in your inlet pipes. try running the pcv breather into a coke can temporarily just to see if thats where the oil is coming from. you mentioned you wre running the motor in on low boost but were you also putiing it under high load - 3 passengers and steep hills to prevent the bores from glazing?

[Amaru]

Yeah when it was running in I followed everything I was told, putting it under load (going up a steep hill in 4th/5th gear at low rpm with two guys in it, me and my friend, and were not exactly small :Oops: ) never idle for too long, always varying rpm so never to keep it on a constant rpm and accelerating from 50km/h in 4th/5th upto 4500/5000rpm then backing off. Im pretty confident it was all run in properly.

[benjiman74]

sounds like your on the money! try the can as a first step in a process of elimination and let us know

[Amaru]

Will do, have already lined up a catch can to install tonight. Thanks for your help, will let you know how it goes