I understand that oil will thin when hot, but after mowing for an hour, if I idle down, the oil pressure drops below 10lbs. (have an aftermarket gauge installed)
I replaced the rod and main bearings this winter and measured them with plastigauge. The clearance with the new bearings came out to 2 thousandths (.002) which is within spec. The crank measured within spec for .010 under. (I didn't write these journal size numbers down in my manual)
The crank was turned .010 under 10 years ago.
I used assembly lube and pre-filled the oil lines prior to starting. The engine was "broke in" during the winter with fresh light oil (5w30) and in the spring changed the oil and am now running 15w40. I "think" I have done this process as well as I could.
Per the aftermarket hourmeter I have installed, I now have 7.2 hours on the new bearings. When cold at idle, I have 19lbs of oil pressure and 37lbs at working RPM's (wide open throttle).
This is the cold (70 degrees) idle oil pressure.
This is the cold (70 degrees) wide open throttle oil pressure.
I have no reason to suspect the gauge. Is this normal? Am I expecting too much? Do I need to replace my oil pressure regulator spring?
