I recently had a fun day wheeling, which ended poorly when i got stuck in a deep mud hole and sucked a bunch of water and mud into the oil pan.

So i replaced the oil pump and rear main seal whlle i was in there. Removed the spark plugs and turned her over. nothing came out of the cylinders. Reinstalled the plugs and she fired right up. Idles smooth and oil pressure right in the middle of the gauge. Took her for a test drive and all went well, except the oil pressure dropped to 0 when i put it in gear(didnt notice till i got back).

Any ideas where to start?

 

pics for attention

 

First and foremost, make sure your gauge is accurate.

You had mud in your oil pan? Or do you mean you sucked water through the intake and hydrolocked it? These are two different things and Im honestly not sure how one get mud in their oil pan. If you simply sucked water through the intake you should have removed the plugs and cranked it over to push the water out immediately. Letting it sit with water in the cylinders will only have it leak past the rings and wash out the oil. You may a bigger issue on your hands if you're truly seeing 0psi for oil pressure. Did you check bearing clearances while the pan was off?

 

Snorkel, air filter, TB and intake Mani we're all dry. Idk how it got there. I did blow the plugs out right away. Bearings looked fine and retorqued to spec. 40psi at idle. 0psi in gear. * Update. Did an oil change and added Lucas to it and the pressure seems fine. I'm still not convinced.