Oil Pressure Gauge

[skyliner34bradsta]

Hi there to all sau members,i am new in the scene on here in the forums but i would love to know if someone could please enlighten me on why my oil pressure gauge is so low,i will explain first... i did a service on my car last week changed spark plugs put new oil and oil filter etc etc the only thing that changed was the oil i used motul turbo light last time and it is 10w 40 and this time i used motul 8100 5w 40 and since this change i have noticed my gauge at idle drops down to near 1 bar and when i accelerate it goes up as normal why would this happen?? but on the other hand my car is going better than it has in the past lol,i have checked for oil leaks and there is nothing so this has got me stummped...

any help would be much appreciated

cheers guys

Brad

[llama_au]

Thinner oil means less oil pressure.

[skyliner34bradsta]

Thinner oil means less oil pressure.

thanx so much was just a bit worried thats all

[paulr33]

are you sure that's right? with 5w 40 or 10w 40 i would expect for a good condition motor to have 2kgcm2 at idle. ill check the nissan factory specs but 1 kgcm2 at idle sounds too low

[paulr33]

yep you are correct and im wrong, oil pressure (at least for ECR33 RB25DET) is

1.1kgcm2 at idle

3.5kgcm2 at 2000rpm

5.6kgcm2 at 6000rpm

i always assumed it was meant to be 2.0kgcm2 at idle

ive never seen near 1kgcm2 at idle on my car, its always 2kgcm2 at idle

but i do put in 5l each time and usually go for 5w40 but rb25 + 230k on the ODO

[slinky-minky]

Mine sits at about 3.5 at idle and 4 @ 2,000 rpm reaching a max of close to 5 when you put your foot down. That makes it sound as if perhaps last time it was serviced that used too thick of oil....thoughts?

[paulr33]

or not enough oil or too much

check the oil level when the engine is hot using dipstick

[blind_elk]

yep you are correct and im wrong, oil pressure (at least for ECR33 RB25DET) is

1.1kgcm2 at idle

3.5kgcm2 at 2000rpm

5.6kgcm2 at 6000rpm

i always assumed it was meant to be 2.0kgcm2 at idle

ive never seen near 1kgcm2 at idle on my car, its always 2kgcm2 at idle

but i do put in 5l each time and usually go for 5w40 but rb25 + 230k on the ODO

Those figures are based on the recommended oil from Nissan. And the 5W / 10W figures are irrelevant to this - they are cold start viscosities.

Different oils behave differently when warm, under shear. It's not unlikely that 2 supposedly identical oils (both 40s) should give different pressure readings under the same engine conditions.