Is there a serial# or year that you can tell if you have the 11 psi or the 30 psi spring in the block? I'm having similar oil pressure/ temp issues as other people posted and I don't want to have to pull this ***** out again! Any info would be appreciated. Has any one changed this out in the boat before?

Kennyo,
One of our pan engineers moonlights at night building offshore engines, I asked him, he doesn't know of number that details which pressure bypass, but they remove and block on all rebuilds. This is after a new Melling M77hv is installed and re-shimmed for adequate pressure.

Chris

The part # for the 30lb bypass valve is 25161284. It is used in the 6.5L Diesel with an external oil cooler. It can be changed with the engine in the boat if you have room and like working upside down. Good luck.

I block them off. Do not trust even the higher pressure one.

Use a good quality filter with an internal bypass.