Oil Pressure

[benflyn]

Is it a problem or a dilemma?
Lycoming O-320-B2A, 0 to fifty hours break in with aeroshell 80, fifty to fifty five, chevron areo AD 20W-50. Oil temp 180 or lower, oil pressure mid seventies at cruise rpm. When the oil temp is 200 or so the oil pressure is mid seventies until 1500 rpm then above that it drops to 45-50, drop the revs to 1500 or lower the pressure is back up to the mid 70’s. Sump level is at 6 quart mark
Is it an oil related issue or is the pressure regulating spring T U?

Any ideas are appreciated.

Thanks!
Benflyn

 

[Steve Pierce]

You have the wrong oil pressure cap. I bet they changed your seat out at overhaul and you are still using the old style cap. Been there and done it. Weird to pull the throttle back and the oil pressure go up. The new style has an adjusting nut and stud built into it. I can't remember if the old style is a cage or just a seat without looking at some of the cases I have at the shop.

 

[Steve Pierce]

I think the old style is the caged seat and the new style incorporates the cage in the cap that screws into the case and holds the oil pressure relief valve spring and ball.

 

[benflyn]

Bullseye!

SB-1172

Lyc. Kit # 972629

Thanks Steve for the info.

 

[benflyn]

spring part #

lyc. kit 972529, what is the part # of the spring? O-320-B2A

Thanks!