C2 Oil Pressure High

[Mike M.]

I changed over to 10W30 from the 15W40 diesel oil. It lowered my oil pressure a bit. About 10lbs, at idle. Its running just under 30lbs now at idle, but just under 60lbs. at 2500 to 3000 rpm. Is this pressure to high to pass the performance verification test? If the pressure is to high to pass the PV it looks like my only option is to change the spring in the oil pump. The PV manual says after full warm up normal readings are typically mid range above idle. It looks like 30 to 40lbs. would be correct or that is what they are looking for. What type of pressure are most of you getting? I talked to the melling rep. and the part number for the oil pump spring that Joe give me to lower the pressure will work in the melling pump. Any thoughts on this would be great. I'm not looking forward to dropping the pan. Thanks Mike

[Clem Z.]

Re: C2 Oil Pressure High

mike check around for some lighter oil as changing oil is easier that changing the pump spring. try some straight weight oils as that is what the engine came with back in 65. the SAE specs for your 65 350 HP engine are SAE 20 W and the oil pressure is 30-45 PSI at 1500 RPM

[Mike M.]

Re: C2 Oil Pressure High

Clem, I was thinking of trying that but I thought a 20w would be to light in the summer when temps were around 90. When I first got the car I ran straight 30w. Would the oil pressure change much from 30-45 PSI at 1500 RPM to 3500RPM? As long as I can get it in the ballpark it should pass that part of the PV test.
Thanks Mike

[Clem Z.]

Re: C2 Oil Pressure High

mike you will have to try it and see what happens. you could just use the 20W for you PV test and then switch back to 10 W-30 multi vis for you everyday driving

[Mike M.]

Re: C2 Oil Pressure High

Clem, I'll try it and see what happens. It would sure beat changing the spring.
Thanks Mike

[Mark H.]

Re: C2 Oil Pressure High

Just curious - with pressure of 35-40 psi at 1500 rpm, what pressure would you see at idle?

[Clem Z.]

Re: C2 Oil Pressure High

the oil pressure is determined by the clearance built into the engine bearings