Doug Rohrer

Well Known Member
My RV-9A with an O-320 has always had relatively high oil pressure, 70-80 psi. Lately, I am seeing redline pressure (90 psi) on climb out and full power cruise. I have to cut back 200 rpm to drop the pressure below redline. The problem will only get worse with cooler weather. How do I reduce oil pressure? I did not build this plane. Oil is Aeroshell 20W50.
 
First, test your oil pressure gauge to confirm that it is correct.

Oil pressure is easy to adjust. Check with a local mechanic, or Lycoming overhaul manual.