oil pressure & temperature problem

[Antx]

Hello

I have a newly built b18 motor. There's no oil leak as I see from above or under the car and the oil level on the stick is on the maximum line.

Since the motor is just built, I put Mobil 1000_20-50 non-synthetic oil. The pressure while the motor is cold is 60 psi (or more) at 3000 rpm. While the car gets warmer, pressure starts to drop. When the car gets to the working temperature, the oil pressure drops to 30-35 psi at 3000 rpm.

As I check from the service manual, this is not normal.
Is this a problem of oil or oil pump or ?another thing

 

[mirrorimg]

Did you plastigauge the bearings? Improper tolerances could cause poor oil pressure because of excessive gap.

What is your PSI at idle, after the car is warmed up?

 

[Antx]

After warming up, PSI at idle is less than 7 or 8 smth like that.

Which bearings are those ? I have to ask that.

 

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Rod and Main bearings, they are pretty much the only "bearings" in the block. I know for a B18A1/B1, PSI should not drop below 10 at idle. Try hooking up another gauge to make sure its not a faulty gauge.

 

[Antx]

ok - I'll try another gauge..