High Oil Pressure? (7 replies)
I have just started driving my recently purchased mk3 cooper S and have noticed that the oil pressure is around 100 PSI when I first start the engine and drops
I have just started driving my recently purchased mk3 cooper S and have noticed that the oil pressure is around 100 PSI when I first start the engine and drops to about 50/40 PSI when the engine is at normal temperature. Is this too high or quite normal.
I did wonder if the oil pressure release value is OK.
No, its not normal. Should be 75psi at 4000 rpm. You either have a bearing problem or the oil pump is on its way out, most probably its bearing failure...sorry....
Not what I really want to hear but appreciate your help. When you say bearing failure I assume you mean main bearing for the crankshaft. I am a little surprised as the car has only done just over 11,000 miles. What type of damage would you expect to see? Is it worth getting the oil pressure check via a different oil pressure gauge from a garage?
My mk3 also runs 100psi when cold then drops to around 50psi when warm and the engine is fine.
You should check the pressure regulating valve just near the oilpressure takeoff on the block.
It's a big bolt about 1 inch with a spring loaded bullet behind. If the former rebuilder /owner has done something wrong it could be there.
On all mini's there is a bullet shaped thing that shut's the pressure untill it reaches it's neede pressure and let seep out the extended oil into the gearbox back.
On cooper 's' this was a ball like one found in bearings about 8 mm big.
If one convert's a bullet to a ball bearing you have to shorten the spring or the pressure it will open is to high ( like what could be your problem).
It's an easy check and can be changed easy.
It would be strange to me ,lik Roli said , if the bearings or whatever in the oilway's would get tyred , the oilpressure would go up?? It would go down in my opinion.
Thanks for your response to my post. I must say that my mk3 is running really well at the moment. I just balanced the carbs this weekend and the engine is ticking over really nice.
just removed my carbs now and overhauling them where abouts are u tony