Rb25det Oil Pressure Sky High!

[scr33min']

Hi guys,

Im new to this forum, so hopefully ive posted this in the right place

I own a 1993 r33, and the other night I was on a cruise with a few mates. Didnt do anything stupid, just boosted it a couple of times. And everything was fine and dandy.

but the next morning when I started the car, some white smoke started coming out the exhaust. it was noticable from the rear view mirror. So i got out and had a look and either put it down to condensation, or a blow head gasket :S

In the afternoon i had to go down the road to pick up some things, and was worried about this white smoke. Started the car, no smoke. When i got to where i was going i got out and checked again to see the smoke and there was hardly any at all.

Got back in the car and drove home and havent seen any white smoke since. but when i started it the idle was kind of lumpy.

On the way home though i noticed the oil pressure guage and the oil pressure was going between 80-100 psi! (the guage only goes to 100)

After a while it did drop down to 50-70psi though, but took a good 10-15 mins of driving for it to do so.

Is this normal for these kind of engines?

What oil pressure should i be running at?

It never did this before and its got me confused and worried. But yet the car seems to be running perfectly fine otherwise :S

Any help is much appreciated!!

[Dobz]

What oil are you running?

[scr33min']

pretty sure is valvoline xld 20w50

[NYTSKY]

Its normal for oil pressure to be high when the motor/oil is cold.

Pressure gets lower as the oil heats up.

[scr33min']

So its fine to go past 100psi while driving cold until it warms up?

[boiracer]

dont give it too much curry till that pressure drops down, and XLD 20/50 isnt entirely ideal for a skyline (there is a whole thread about oils on here).

not sure on those pressure numbers as mine only has a standard gauge. but your smoke does sound like something to worry about....unless its just miles over full with oil, and your driveway is at a funny or steep angle. in which case that would be your answer.

(my old beetle occasionally blows a puff or 2 of oil smoke if it sits at the wrong angle in my parents front yard. but being a Boxer and running far more oil than standard its merely oil seeping past rings a little)....having said that a skyline aint no boxer....and your oil shouldnt be anywhere near the rings while stationary to cause this.

is it still getting boost and running fine?? does the lumpy idle clear up? if it is burning oil your pugs might gunk up and cause the lumpyness.

[boostn0199]

Its normsl for that pressure when cold and should settle to around 40 to 50 psi when warm.

[Moodles2]

Valvoline XLD 20w50 at $25 per bottle.. no expenses spared. I would start using a 10w40 unless there is a reason why your going cheap with such a thick oil (mask oil usage, don't expect the engine to last etc)

[Dobz]

Valvoline XLD 20w50 at $25 per bottle.. no expenses spared. I would start using a 10w40 unless there is a reason why your going cheap with such a thick oil (mask oil usage, don't expect the engine to last etc)

+1

20w50 is way too thick for your engine.

[scr33min']

I didnt put that oil in there the guy who had it before my did.

thats why i wasnt 100% sure what it is.

Do you reckon thats the cause of the high oil pressure?

I was having a read around and found that it may be caused by a blockage or someting. like a clogged oil filter?

I took some videos today of the guage when i first started it, and also what its like after a 20 min drive, where i was driving like a grandma.

If someone knows how i could do it, i can post up the vids as it probably explains it better then words

cheers for the help so far though!

[Moodles2]

Firs thing you should do when you buy a car... dump the oil, change the fitler and put a decent 10w40 in there.

100psi is 7 kg/cm2. stock gauges read up to 8kg/cm2 so 100psi isnt anything to worry about, I see about 4kg/cm2 (60psi) to 6kg/cm2 (85psi) during a cold start, although I run the correct oil.

[scr33min']

ok thats the first thing ill do tomorow then

So, best oil to use. Royal purple?

Or would a 10w40 from the local auto shop do just fine?

[Moodles2]

When Repco have 20% of Motul oils, go for Motul 4100 Turbolight 10w40 is porbably the best semi-synth or if you want a full-synthetic Motul 8100 X-cess 5w40/Motul X-Max 10w40

On a budget people have success with Gulf western Syn-X 3000 (10w40)

Royal Purple is good too though pricey

edit: if you want RP cheap, try: http://performancelub.com/

[scr33min']

I know its been a while since i last posted, but i just cant seem to pix the issue!!

Ive replaced the oil, with a nice 10w40. I also pulled the intake pipe off from the turbo and found a bit of oil in it which i thought would mean a bad pcv valve. So, i pulled the pcv valve off and gave it a clean.

You could hear the ball rattling around inside which ive heard is a good sign and i could blow through it one way and not the other.

Took it to a mate who is a mechanic and he put some stuff in the radiator which he said should "fix" the headgasket, if it was the headgasket.

Well, whatever it was the car no longer has water/steam and white smoke coming from the exhaust so thats a good sign.

Im still confused as to what would make my oil presure so high?? and the car still idles a bit bad for the first 5 mins on startup.

Im thinking it could be a bad oil pump? or pressure relief valve?

[Moodles2]

Oil in the intake can come from anywhere, turbo seals, blowby (piston rings etc).. as I said before 20w50 can be used to mask these things.

I hope he didn't put a bottle of chemiweld to fix the headgasket, that stuff is nasty.. I would only put it in a shitbox. As for smoke I would be doing a leakdown test to see if there really is a problem with the head gasket, piston rings etc.

As for idling like crap I think that's normal for cold RBs, I know mine does in the first couple of mins. In your case you might have a problem with your cooling system that is causing it to take forever for it to get up to temperature (wrong thermostat or thermostat stuck open, aftermarket oil cooler without a oil thermostat etc)

Oil pressure is linked to engine temperature, if the engine is cold pressure is high, when the engine is at operating temperature it's low.

[Galois]

Running a good oil containing plenty of detergents (a good quality oil), may help clear any blockages/build ups of crap in the engine. It may take some time though.

[scr33min']

I hope its as simple as a blockage and hopefully will go away its doing my head in

Ive taken note of the pressure level at each rpm and it seems to go way out of wack.

Another thread on here stated its suposed to be:

14psi @ idle

50psi @ 2000 rpm

80psi @ 6000 rpm

Now, im getting:

just above 20 psi @ idle

60psi @ 2000

80psi @3000

This is all when the engine is warm by the way.

Thats a hell of a difference!

Im too scared to take it over 3000 rpm in case something blows out.

Im so cinfused as to what could be causing this.

And Moodles, i dont think he put chemiweld in it, because the stuff costed like $170 compared to the $10 chemiweld

thanks for the help so far guys!

Edited October 2, 2011 by scr33min'

[Moodles2]

If the previous owner put Valvoline in, then he has probably been putting in whatever was on special at Supercheap... in high likely there could be sludge as the result of cheap oil (magnatec is known to do this) causing high oil pressure by blocking the oil galleries, oil restrictors, turbo oil line etc. Shine a torch into the oil cap opening and take a pic

[Thelen]

Something is very wrong, take to mechanic... $50 inspection, $5000 rebuild...