Fearing the worst.

[boro drift]

That's not possible...think about it.

Because of the baffles in the valve covers?

 

[jdub]

The rings are on the pistons, correct? At what point in a 4 stroke engine cycle does the piston produce a vacuum in the cylinder...the intake stroke, with the intake valves open. Fluid flow (including the A/F mixture) will follow the path of least resistance. The vacuum produced during the intake stroke will simply pull the A/F mix in...there is no way it is high enough to pull any sufficient quantity of oil past the valve seals (assuming the seals are good).

If you are talking about vacuum being exerted on the intake manifold, that is typically 17-25 Hg/in depending on engine speed. It doesn't change due to the rings...it's a function of cylinder volume and valve timing. The PCV system is designed for it...it's whole purpose is to pull crankcase vapor into the intake/plenum and rid the oil of combustion byproducts. Pulling liquid oil up through the valve covers is impossible...and, yes the valve cover baffles are in the way. Read this:
http://www.cygnusx1.net/supra/TechTips/vacuum_gauge_readings.aspx

Whoever told you that is making up "facts" as they go.

 

[boro drift]

Now that I think about it, I agree. Theres no way the pcv system will pull oil.

But, the leak-down test confirms the rings are good. The crank case was breathing freely,(not under vacuum, but breathing freely), so where did the oil come from? Gotta be the turbo.

 

[jdub]

Assuming a compression test confirms the leak-down results, I would be looking at that turbo too.
I figured you come to that conclusion...just took a little prompting

 

[boro drift]

I'll try and run that compression test this weekend, then I'll post back. I'll also try and get my pcv pipe fixed.

Thanks for hanging in there with me jdub, I appreciate all your wisdom! I've built several engines with great success, but this just goes to show, I don't know it all.

 

[Rennat]

i know each engine is different, but i had some oil eatting problems... did a compression, did a leak down test... couldnt figure it out, pulled the intake manifold off and found some nice puddles of oil in the runners, my valve stem seals were torn to shit.

fixed those and no more oil problem! but i would defintaley get a tube from the valve covers to the intake...

 

[boro drift]

Compression test results,

#1. 155psi

#2. 155psi

#3. 155psi

#4. 158psi

#5. 160psi

#6. 158psi


I also put my pcv system back to stock.

Now if I can get code 52 taken care of, I'll be dialed, for now.

 

[IJ.]

Do a leakdown test as well

the comp numbers are close enough.

 

[boro drift]

Do a leakdown test as well

the comp numbers are close enough.

I did that first, and the results were great. jdub wanted a compression test to verify the leakdown test results.

 

[IJ.]

LOL the Mod staff share a braincell

 

[jdub]

Seems like it sometimes!

Sure looks like your rings are seated just fine...take a good hard look at the turbo.

 

[boro drift]

Sure looks like your rings are seated just fine...

...and I'm releived! I really didn't want to pull the engine this winter for a re-ring.

So now I guess I need to start buying parts so I can tune, (turbo,fuel,engine management). jdub, what would be a good set up for 450 rwhp?