Had to happen right in the middle of the season (north east). We had a ton of rain over the past ~2/3 weeks here in NJ and my guess is the drain plug clogged and there was a high water mark about 3/4 ways up the crank pulley. During a pre-check I found a very high oil mark on the dip stick, decided to pump out a little oil to get a better sense of what is going on and got nothing but fresh water for about 10qts. Pumped the entire pan so now it's dry. There is no question that the motor has to come out at this point. I've wanted to change the pan anyways and do a few other minor maint tasks but with that level of water in the crankcase is there anything else I should do while the motor is out? The engine hasn't been cranked since the water got in. It's a 540 carb /w remote oil filter and oil cooler (was also underwater) for what it's worth

I wouldn't be so quick about pulling the motor. The water most likely entered the pan through the dipstick tube. I would replace the oil/filter and run in. Any residual water should evaporate once you build up some temp.

^^^^^^ Agree! Being it was freshwater I wouldn't pull the engine. New oil and filter, run the engine up to temp, check for foaming/discoloration. If it looks like caramel milkshake, repeat until oil is clear.

Wow. That's some pretty great news! Save the maint tasks for the end of the season and save a few $$$

make sure you're watching the oil pressure when started, if its ok smear some black rtv around the tube where it goes in the pan.

I would buy some cheap oil and run the engine to temp while watching oil pressure. If the oil pressure is still good once its gotten nice and hot I would change the oil again. It will probably be slightly milky. You may have to do this a few times before the oil is clean again which at that point I would fill it with your regular oil and keep boating!

Let me ask this. What's the general consensus worst case scenario if I do the run and flush method vs. pulling the motor and replacing the pan/dip stick and whatnot. I'm all for not spending $1500+ on pulling/installing the motor and changing the pan during the season but if it means I could destroy a ~10k motor... well.

k5 are you a marine mechanic ?

I have done the above mentioned method several times on boats that have completely sunk and never had an issue...I would also pull the plugs and roll the motor over without plugs in it just to verify there's no water on top of the pistons...I know its a scary thing to have water in the motor but as long as you didn't run it with the water in the oil you should be fine...usually takes 3-4 oil changes to get all the water out from my experience but that was on motors that were completely under water

Like they said above as long as you watch the oil pressure gauge and get it up to temp it will burn all the water out...don't be alarmed if you see extra condensation and a lot of steam on the first fire...it happens lol