N1 Gtr-32 Oil Pumps

[[200]]

Just a bit of info which someone maybe able to shed some light on, 92 psi @ idle, is this roght for this pump any specs etc would be much appreciated

cheers.

I have checked the pump and it is an N1 item, way to mjuch oil pressure though, maybe a releif valve problem?

[carl h]

is the gauge correct?

what kind of oil?

what kind of ambient temps?

it might be a bad gauge or it might just be cold oil, worst case senario its a bad pump.

[[200]]

8100 oil

normal operating temperature

oil pressure has been checked with 3 different guages, 2 mechanical and 1 electrical, all say 92 psi at idle, engine is in good condition otherwise

[PHATR32]

hows the oil filter? maybe its dirty and blocked?

[[200]]

oil filter has been changed several times to eliminate it causing the problem. However, releif valve should be open if there is a restriction in that area.I seem to think that it maybe jammed closed and not operating at all ! I have taken it apart to check spring etc, found 2 shims under the retaining bolt, and also took aparta brand new N1 pump and found no shims ! they are only 1mm total thickness, harldy enough to change base oil pressure at idle by 65psi !

[carl h]

even if the shimming is only ~1mm you would be suprised what it can do to spring rates...

[[200]]

I have checked the spring rate, it is a linear spring and the same spring rate as a standard gtr 32 pump, the satndard pump i was comparing had 1 shim(0.5mm) the pump on the car which i am having problems with has 2 (1.0mm) and the brand new, unused N! pump had none !

Hence i dont think that this is the problem

[Turbine]

I use a rule of thumb of 10 PSI per 1000RPM.

This 92PSI @ Idle sounds extreme.

Also when changing shim sizes, I have found on average for a pump this size (Pressure vs Volume) that as little as 0.010" can change the pressure 4PSI around the 100 mark.

Your releif valve could be just jammed shut?

[[200]]

THATS WHAT IM THINKING, REPLACE THE PUMPS AND TRY AGAIN, BUT IF THAT DOESNT FIX IT, MAN THESE ENGINES TAKE A BIT OF EFFORT TO R&R

[Amaru]

Do you or your engine builder have access to an engine dyno? Alot easier to quickly start it up on that to see what the pressure is than r&r'ing it all the time.

[[200]]

JUST A cHASSIS DYNO AT WORK. sTILL HAVENT FOUND ANYTHING OBVIOUS THAT WOULD BE CAUSING THE PROBLEM, THE BLOCK HAS A TOMEI RESTRICTOR (1.5MM) BUT THESE HAVE BEEN IN OTHER ENGINES WITH NO DRAMAS SO IM RULING THAT OUT ALSO

[PHATR32]

dude, turn your caps lock off

[[200]]

SoRrY

[T04GTR]

ok... 92 pound is pretty normal.

my 200k old 32gtr runs:

cold start up. 6 bar

rev it abit goes up to 7.6bar

when the oil is at 80 degrees:

2.5 bar at idle 4bar by 3500 6bar @ 5000

its not a 253 mate.

thats some normal shiet, dont stresss

[T04GTR]

NORMAL

[SteveL]

ok... 92 pound is pretty normal.

No that's not normal for an engine at idle and the oil at normal operating temp, as per the OP. For a stock oil pump and engine in good nick, an R32 GTR should have oil pressure of about 20psi at idle. The N1 oil pump has an increased spring rate on the relief valve to boost oil pressure, but at idle that should only give an increase of maybe 5psi at most, and certainly 92psi is way too much. Frankly I'm a little sceptical at such a high reading, esp at idle and would want to have it triple checked using a _calibrated_ gauge, but the cause is probably related to the relief valve and that needs to be checked.

[[200]]

SteveL, I would have to agree with you, as for checking the oil pressure, 3 guages have been used, all calibrated and all read as explained.92 psi at idle i believe is excessive, this is also at normal operating temperature ! Also, oil pressure doesnt change through out the rpm range as indicated by an increase in oil pump speed.I dont think that the relief vavle can hold such pressure when rpm increases, simple maths says, increase flow rate(pumps rpm) must be proportional to pressure head.Given the standard 10 psi per 1000 rpm, @ 6000 i would have approx 150 psi !, this is not the case, checked , re checked and checked again, oil pressure remains at an indicated 92 psi.

Its got me stumped

[Turbine]

200

Have you checked the pressure with analog gauges or 3 standard nissan in dash units?

If you havent tried this, then get hold of a mechanical analog gauge, say 0 - 100 psig, see what happens.

You may have an electrical fault, sending the wrong current through the gauge. Because you said that it's at 95 pretty much all the time, it's like an alternator with it's current load when charging, kind of constant.???

Just a thought.

Glenn

[r33_racer]

Im pretty sure he did say 2 mechanical gauges and 1 electrical gauge...sounds like hes in a workshop or works for a workshop so im guessing you didnt try three std gauges? And im guessing they tried the same gauges on another car to make sure it wasnt reading 92psi...seriously what are the chances of three gauges all stuffing up at the same time?

There isnt some highly unlikely piece of shit or something that is blocking the gallery to the oil pressure sender feed and causing whatever amount of flow to equal 92psi? Just thinking outside the usual square here especially since the basics have been checked.

[Beer Baron]

i have had excessive oil pressure before on an SR20 (in a GTI-R). pulled off oil filter, poked finger around in there, problem went away. dont know if that will help, but it helped me!