Looking for some suggestions before I go through the headache of pulling the motor. I have a 2003 Malibu Response LXI with the Monsoon 335. I have never had any oil pressure issues until about half way through this season. The oil pressure used to read around 40psi at idle and climb to maybe 60psi at 34 mph. This year the idle psi is closer to 60 and if I take the boat to 3500 rpm for more than a couple of seconds the pressure climbs to 80 and the alarm goes off. So far I have changed the oil filter, pressure switch and the pressure sensor. The readings are staying the same and the alarm goes off at 34mph. Any suggestions for what else I can look for? From searching on line it sounds like it might be the check valve in the oil pan.