So when I start the car cold it takes about 5 minutes for the oil pressure to drop from about 60 to about 25-30. Is that normal with the OCC??

I watched the gauge as the rpm starts at about 1200 when cold then dropping to about 750 when warm. Meanwhile the oil pressure follows up with a drop from a 60 at start up to about 25-30.

Any ideas?

 

Nothing to do at all with your OCC...

Yes that is normal.

You proably have a gauge after vehicles with "dummy lights".
Those go on with very LOW oil pressure.

Now you know what is really happening because you have a gauge.

 

Actually no lights but indicator arms on both the boost and oil pressure gauges.

 

Sorry... met to say "you proably HAVE HAD vehicles with ONLY lights".

What you are seeing now on your gauge is true for all vehicles

 

Oil viscosity or thickness changes with temperature. When the oil is cold and thickest, it creates more pressure as it is pumped around the oilways. As the car warms up, say after the oil temperature gets above 100F, the oil will begin to thin and the pressure will drop. Multigrade and multigrade sythetic oils have two numbers associated with them. This is often referred to as the 'weight' off the oil. The oil has to be thin enough for cold starting and yet thick enough for highway driving on very hot days. So the Society of Automotive Engineers (SAE) developed a system of meaurement that heats the oil and measures how long it takes to flow through a calibrated diameter hole. The two SAE numbers indicates the oil's performance at 0F and at 200F. The oil used in the MINI is SAE 5/30. So as your car engine warms up, and the oil thins and the pressure in the oil system drops.

 

That was very informative. Thank you.

 

My pressure on startup is also around 60psi.....

When warmed up it goes all the way down to 12.5.

When I get on the gas pedal it gets up to about 55.

Using 5w 30 oil as well.

 

100% correct statement.

 

I talked about the relationship between engine temp and oil pressure, there is also a direct correlation between engine speed and oil pressure as the oil pump is driven by the engine crank. The faster the engine, the faster the pump and the higher the pressure. There is also an oil pressure release valve that releases within the oil system if excessive pressure is produced and just bleeds oil back into the sump. One the engine is hot, you will see lower presures at idle, than when cold, but when running you will see mid-range values.

 

That's almost what happens to me as far as those numbers. When I blew off my valve cover gasket the oil pressure was hovering between 75 to 90 at idle

 

I would have thought that the PCV valve would have vented that pressure in the valve cover.

The oil is being pumped UP to the cam and valve cover area and it "'falls" back down.
I dont think the oil pressure and volume would be able to compress all the air in the valve cover and blow it off.

UNLESS you had other issues... like a bad PCV, or an improperly plumed OCC.

 

i'll go with improperly plumbed occ for a thousand alex .

 

I think a good bet

 

That is correcet. The OCC's hose was being pinched when installed hence the pressure of 75-90. The problem has since been corrected, thank god.

 

I have a 2006 Mini cooper ss automatic with a little over 52000 miles. My oil pressure is great when engine is cold to warm and rpm is around 1200. After it warms up it drops to around 1000, 750 and the gauge goes first to zero at a stop and when accelerated increases and drops back to zero at zero oil light also come on. Then after fully warmed up it stays on regardless of rpm or acceleration.. I just had the oil and filter changed and it seemed at first to correct the problem. Tonight I did notice it took longer but it's back to dropping to zero and the light also comes on regardless of acceleration. I just purchased the car which came with all the paperwork from the first two owners which seems it was taken care of and the receipts show care taken.