coolant issue on 12 v 92s

Yeah, anytime you have water or non-compressable fluid in the cylinders, it is going to put all kinds of strain on the bottom end of the motor. I had a Donzi with the then new Vortec 350, which had too much advance on the camshaft or something when they first introduced it. Turns out it would injest water from the exhaust risers due to the camshaft advance. Well the motor ran liked a raped ape 2 trips, then all of a sudden it kept losing and picking up oil pressure. Take the motor apart and it spun a few crank bearings and by that time the problem was known in the industry. Longer risers helped greatly also turns out.

I would do a major and mic. all of the crankshaft journals as well as the block where the sleeves go both at the top, middle, and bottom. I have seen them get egg shaped.

I'm guessing you went into the sump for a check out or check the rods to the wet cylinders.
Large washers in the pan would come from cam gear ends or PTO hardware. Some washers are used holding the plumbing up on oil & scavenging pump pickups.
If your having cam end hardware problems, previous owners / mechanics may had already been there. Until you find something real major with the block (it was running) or don't have the room for in-frame service, why pull?

I remember dropping my two-piece pan on our 12v71s. Found all kinds of loose hardware. Mostly from years of dropping hardware during injector, rack, valve service down the oil return galley. Found an extra oil pressure relief valve also.
No gold or jewels.

If the crank is in good shape, usually, the block can stay in the boat. Pulling those long cam shafts may need some extra fore/aft room.

You can pull the crankshaft out and leave the block. If the block is in good shape than it doesn't need to be taken out of the boat. If the motor wasn't seriously overheated, the block is generally fine. Some blocks came out of DD as problem childs with egg shaped bores as well, you just need to measure them to see where they're at.

I had a couple of bad holes where my liners fit poorly in the block (12v71s) and my shop cleaned them up (block holes) while in the boat. I'm sure but not positive that 92s use similar liner technology and can be replaced and serviced like my 71s; Any issues with the block / liner fit can be corrected in frame.
Any thing is possible on a crank. Yes, raise the block and drop the crank. Need a bunch of kids with strong backs, not from the same hood, to lift it out of there.

On the other hand, unlike 12v71s (one piece block and crank), is a 12v92 just 2 X 6v92 blocks? One or 2 piece crank? or was that just for the 16Vs?

I may remember some (or learn) more DDC stuff here in a while.

I would thing crank bore alignment an decking are really the only things that a good block has to come out for.

In the end play, Sometimes IT JUST MAY be easier to rebuild in a shop. My old back would prefer it. Let somebodys else's back get abused putting that long block back into the boat.

Well then, the world is full of possibility's. Anything can come out, stay in, come out & in.
Pushing my thoughts; I'm assuming two piece cams?

I did read an article about a Penski project; 24v71s. Still day dream about that.

A friend of mine ran a motoryacht with a pair of 24v92's. It was a FUEL HOG and always problematic......