What could cause this??

[mhopemk3]

Pulled the head this weekend due to (my thought of leaky valve stem seals). Car will puff on start anfter sitting a while and will puff when coming to a stop when normal driving. The puff is white smoke.. Anyways this is what I found. I did a compression check with these results. These were on 5 turnovers. I cranked it over about 8 times on a few and got up to 180.. I did warm the car up a little. Just let it idle a few minutes. Not norm operating temp though.

Why the oil in 6? Would leaky seals cause this?
1. 160
2. 170
3. 165
4. 165
5. 170
6. 165

 

[rumptis]

Yes...leaky valve stems seals could cause that. If they are leaking the oil will run down the valve and onto the piston.

Why did you pull the head to change the seals...this can be done with the head on the engine?

 

[sleepersupra]

ok i'm glad you wrote this but since you said that it can be done on the car that means that i'll be ok and won't have to worry about my head or block or mhg since i just finished it?

 

[mhopemk3]

Combo of reasons.. Most because I am ready to upgrade Fuel, Injectors yada yada and turn up the boost a bit. So I really wanted to change the HG as well and torque it down.. I just bought this car a little over a year ago and wasn't sure of what had or hadn't been done to it..

 

[rumptis]

ok i'm gald you wrote this but since you said that it can be done on the car that means that i'll be ok and won't have to worry about my head or block or mhg since i just finished it?

I don't see why this would be a concern...If the MHG can handle the high pressures of a boosted engine then why would some oil in the cyclinder cause problems?

 

[joefoe]

I don't see why this would be a concern...If the MHG can handle the high pressures of a boosted engine then why would some oil in the cyclinder cause problems?

It's a big problem becuase oil wil effectivly lower the oct rating of the gas. Lets say you run 91 oct but there is oil in the mix, you boost it pings like a mofo.

 

[rumptis]

I'm not promoting running it like this...or saying its ok...but its not the end of the world as we know it...it needs to be fix. But oil its self is not going to make the HG leak or cause any damage just by its self.

 

[SublimeSupra]

Well actually it could as stated above.Oil and gas mix equals less octane less effective burn.That can lead to detonation under boost which blows HGs.