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914World.com _ 914World Garage _ Very high Oil Pressure when cold ...

Posted by: SirAndy Apr 11 2008, 10:51 PM

so now that my new engine harness is in and all the gauges work as they should, i see that my oil pressure is way high when the car is cold.

i have the 1 - 5 bar(?) gauge for the oil pressure with the matching sending unit. when i start up the car cold, the needle pegs out at the top, slightly above the 5.
it will stay there until the thermostat opens, which seems to be right around 200 F ...

once the TStat is open, the pressure will drop to ~2 at idle and goes up to 5 under load/throttle.

the real issue here is that on a rather cool day/night, like this morning for example, i drove for about 1 hour and the temp never got to 200 and the thermostat never opened.

how long can i run the motor with that much oil pressure? what damage could i be looking at? any suggestions? ignore it?
Andy

Posted by: SLITS Apr 11 2008, 11:47 PM

My 2.4 & 2.7 throw 10 bar on startup ... If they don't suffer from bearing pitting / surface sloughing from 150 psi, then I would hazzard a guess that it wouldn't hurt yours.

But I ain't no Porscheee expert.

Posted by: charliew Apr 12 2008, 09:10 AM

I would think the main concern would be the filter exploding or the filter gasket blowing out. You should try a thinner oil because the thicker oil moves much slower and startup wear is the most wear a motor gets. The thinnest oil you can run and keep reliable pressure when hot is the best thing you can do for the motor. Also the more the oil pump has to recirculate the oil in itself the more it aireates (bubbles) the oil. Ask Jake.
Charliew

Posted by: ConeDodger Apr 12 2008, 10:57 AM

My 3.2 does that as well... I would think it isn't a problem as long as the filter has a pressure relief system...

Posted by: r_towle Apr 12 2008, 12:02 PM

both the 944 and 928 peg the stock gauges at start up.
It may just be a porsche thing.

Rich

Posted by: thesey914 Apr 12 2008, 03:21 PM

Mine does the same. I was worried to start with but I checked the relief pistons thinking they were stuck and they were fine.
From what I've read the pistons open around 90psi (my gauge is 140 psi version)
My gauge was pegging and I've worked out my sender is wrong -it's reading 140 ohms which is the max it should read. Mechanical oil gauge proves i'm running 90psi rather than the 150 the gauge is showing.
10/50 oil in 2.4

Posted by: SirAndy Apr 14 2008, 06:52 PM

Spoke to Rich @ Jerry Woods ...

Nothing to worry about, all is good ...
Andy