Where to start??? (94 Mercruiser 4.3l)

Father in-law gave us a boat that he didn't winterize about 10 years ago.
Boat has 37 hours total on it, and he left it in an unheated barn back in 2000 or so. He drained the oil the next season when he noticed it. Other than that it has always been in a heated garage. Boat is perfect other than water in the block.

Looking around a little and it seems like best case is cracked manifolds, worst is cracked block. Either way I guess I would do bearings, polish crank and maybe rings.

I've built a couple engines with great success, but never marine. I know the marine stuff has to go back on the new block, but what else is there? Could this just be a blown HG, and I flush the block n call it good?

I don't know if I'd be comfortable with replacing HG n running, but is it a possibility? What about aligning the engine to the outdrive? Is that complicated?

All help I appreciate, just got the boat home and know ZIP about it, I'm going out there now to check her out.

Thanks all

Re: Where to start??? (94 Mercruiser 4.3l)

Find out if, and where it is cracked first of all. Start there.

Re: Where to start??? (94 Mercruiser 4.3l)

Do you know that is is cracked at all?

Re: Where to start??? (94 Mercruiser 4.3l)

thumpar said:

Do you know that is is cracked at all?

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I don't, All I know is there is water in the oil. He changed it and it still has water in the oil.

Re: Where to start??? (94 Mercruiser 4.3l)

Time to bite the bullet and get another engine and manifolds.At least the boat was free.

Re: Where to start??? (94 Mercruiser 4.3l)

Inspect the hull closely to make sure it is worthy of a new engine investment. Nobody parks a boat in a barn for no reason. You could probably get a working boat of that vintage for the cost of getting that one seaworthy.

Re: Where to start??? (94 Mercruiser 4.3l)

The 4.3l GM engine is plentiful, and cheap. You should have no problem finding an automotive engine you can convert.

Here is my engine replacement thread: http://forums.iboats.com/showthread.php?t=520824

I took a motor out of a Chevy pickup myself, but Astro vans are probably the most common donor.

Re: Where to start??? (94 Mercruiser 4.3l)

spdracr39 said:

Inspect the hull closely to make sure it is worthy of a new engine investment. Nobody parks a boat in a barn for no reason. You could probably get a working boat of that vintage for the cost of getting that one seaworthy.

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Boat is perfect, story is legit. Parked in a barn one winter after divorce. Been in attached garage before and after that season. Not a scratch on the hull.

Re: Where to start??? (94 Mercruiser 4.3l)

Thank you for the thread I'll check it out. What about the whole engine vin code deal? Do I need to worry about it in a boat or is that just for auto?

What do I need to know about the outdrive? Can I just unbolt engine and pull, or do I need to support all that too?

Re: Where to start??? (94 Mercruiser 4.3l)

The engine serial number will identify the engine properly for you for parts searches, but isn't useful for too much else. If you end up replacing the engine, you'll want to get a replacement that is close year wise. Your engine will be a 92-95 balance shaft motor.

As far as the outdrive, drain it, pull it, and replace the impeller. There are plenty of threads you can search for on there on how to do all these things (Adults only thread at the top of the forum as a start). With only 37 hours on it, there shoudln't be anything else that is going to need too much work. You need to pull the outdrive to pull the engine anyway.

Pulling the engine is really simple. 2 bolts on the back, and 2 bolts for the motor mounts. Disconnect anything that runs from the boat to the motor, and lift. As I mentioned, you'll have to pull the outdrive first.