Is it really dead? (Grassroots Boatersports)...

After getting my 4.3L Mercruiser V6 boat ready for the season, I went out on the (freshwater) lake for about 5 minutes (2000-3000 rpms, one pull onto plane and then stopped) and looked under the engine cover.  I found a small lake of milkshake on top of the intake manifold, dripping down the sides of the block, and sprayed a bit up the carb and rear bulkhead. I immediately idled back to dock, where it died (conveniently) right as I pulled up to the dock.  

Without looking at it, the boatyard where I store it says "cracked block."  Is it?  Could it be the intake manifold gasket?  There's no milkshake in the water coming out of the cooling system.

It still easily cranks over, but there is heavy milkshake on top of the engine, and on the dipstick.  I'm thinking of pulling the intake manifold and heads, and taking a look.  Even if I can seal everything back up, with the milkshake throughout the block, are the bearings hosed?  Has anyone pulled a boat engine?  How the heck can I get it up out o the boat?  This is a 18' 2000 Mariah I/O (think lake runabout).

Anyone in Seattle want a mechanic special?

If the crankcase is full of water after 5 minutes they are probably correct, it's probably a cracked or corroded block.

That sucks. Other than the whole standing on the head trying to unbolt crap, it should be a pretty straight forward swap to put a engine in it. 

Check your insurance--I know my FIL makes sure to winterize his engine every time he puts the boat away at an actual shop because if the block cracks over the winter his insurance will cover it. But he's in the insurance industry and probably made very sure his policy covered that.

slightly off-topic question - but did you have the engine winterized before the winter? IDK how cold it gets where you are, but if you didn't winterize it, it's certainly possible that water left inside the block froze and cracked the block, not your mid-power run. My parents own a marina here on the Chesapeake Bay (which is generally a warmer climate than Seattle), and i can tell you for sure that all of our boats get fully winterized before the first heavy freeze, and the people who don't winterize (because they go out in the winter) all have block heaters that are plugged in all winter when the boat isn't running. 

The water was drained from the hoses, but I didn't get a chance to fog it before we got our snap cold this past winter, which I'm now kicking myself for!  

The crankcase isn't full of water, but the dipstick does show milkshake on it.  I'll pump the oil out this week and see for sure how much I get out.  Seems like something pressurized the system, which blew the oil out the top of the intake manifold area.... Sucks, as it was really idling smoothly and seemed to run ok for the 5 minutes.

Any preferred ways of getting an engine out?  I saw one really iffy hoist make with 2x4's...

You can probably rent one. 

If you didn't open the drains on the block, it broke the block, most likely just under where the heads and intake meet the block. 

TOO  BAD,  the mercruser, dealer was our go to place for hi po heads and steel cranks, Pink rods, forged pistons in the 70's. Boats had better parts than the avg. car.

Your Intake manifold is cracked.  There is a plug on the front of the manifold that needs to be pulled and drained as part of winterizing. If you didn't run it too long you -MAY- be able to save it with a new manifold and gasket but,  I would count on a new long block. Water gets into the oil and mixes up to the nice milkshake -not good- mixture.  Contact your insurance company.  It may be covered because you tried to winterize it but failed, so you did not neglect it, you just screwed up.  Good luck