Inliners International Forums General Discussion Engines Low oil pressure

Today I noticed my oil pressure hovers under 25psi at idle. Usually for the past year it's been at 45. Anything past idle is usually about 60-65psi. The oil is clean and full. Any ideas?

By the way I have a fairly stock 194 6.

Dear Martin;

"Father Time" is catching up with your engine, guage or both. As long as It's 60# or over (warm) at driving speed(s) your okay.

Happy trails.

I haven't paid attention to my driving speed oil pressure but idle warm its around 20. Ive always heard that 10psi per 1000 RPM for idle and cruise conditions is adequate.

Does that mean it has been changed very recently? If so was the type of oil different, like it is now 10W30 and previously it had been 20W50 or straight 30w? A change in base viscosity will give a change in pressure. Just a thought. My 250 will show 35 lbs at hot idle with 10W30 and 45 lbs hot idle with 20W50. For comparison purposes this engine has not quite 21,000 miles on it.

Hi guys. Thanks for your answers so far.
Mike, the oil was changed about 3 weeks ago.
John, my engine has maybe 40k on it since it was rebuilt. Anywhere above idle it runs about 55psi cold or hot.
The only other thing I can think of are that I now use 10w30 since Jiffy Lube doesn't carry 10w40 or 20w50 anymore.

Did you change your oil filter recently? If your filter is plugged or just differant then you will have oil pressure that is off. I'm not sure which side of the filter your gauge is plumbed to, but I would change the filter before you get too worried.

Dear Martin;

There's really nothing wrong with 55 PSI.

Changing to SAE 30 would bring it up some, but if your happy with multi-grade, that's okay.

Happy trails.

The filter gets changed with every oil change and the original oil cap decal called for 10w30. The pressure is just lower than usual. I just wanted to make sure I'm not about to have an expensive problem.

To start with there is no need or benefit to having your engine run at 60 to 65 PSI oil pressure.High oil pressure is a power robber not a power maker. I wouldn't jump to the conclusion that your engine is on its way out too quickly. First I'd check it for a change in oil viscosity,I'd change the filter and if it still seems low I'd take a look at the oil filter bypass in the block.There should be a spring behind a metal disc that opens to bypass the filter. If that disc is lifting off its seat prematurely its gonna be dumping oil(and oil pressure) Sometimes merely giving that spring a little stretch will do the trick for you but something tells me that spring isnt right anyway if the normal "at speed"oil pressure is 65 but 20 at idle.I've seen oil pumps with shims placed behind the bypass disc in an effort to raise oil pressure above normal,,Have never seen much sense in doing so IF the motor was worth caring for.To my thinking all the elevated pressure was any good for was putting more strain on the rear main seal and inviting it to fail by doing so. BTW normal oil pressure from the engine manual is 25 to 40PSI so yours isnt far from right.

Do you by chance have a Fram filter on your engine?? They are notorious for low oil pressure readings.