big problem 454 xl

[ataylor233]

So I got a deal on a 1993 Carver 350 aft cabin the Starboard engine wasn't properly winterized , as a result there is a crack in the block. I am fully Capable of Rebuilding this engine .. the challenge would be getting it out ... and fixing or Replacing the block.... so my Question is can i used a 454 block from a Chevy truck from around that same time. replacing the Cam of course? using all the other leaving the pistons and other parts? or can this even be Welded

[Viper]

The first thing you need to find out is if that engine is a counter-rotator or not.

[ataylor233]

QR_BBPOST The first thing you need to find out is if that engine is a counter-rotator or not.

OK if it is what would the difference be?

[bud37]

QR_BBPOST or can this even be Welded

Welding an older marine block may not be the best idea IMO ( corrosion and deposits inside where you can't see.).....you would have to get it cleaned/boiled and magnafluxed to be sure of where the damage is actually confined to before proceeding to do it right....are the heads etc ok ?

[buster53]

QR_BBPOST

QR_BBPOST The first thing you need to find out is if that engine is a counter-rotator or not.

OK if it is what would the difference be?

Twin engine boats are all counter rotating engines. On older model boats, the engines were made from the factory to be counter rotating. These days, I’m pretty sure it is all done by the transmission, not the engine.
You need to know what you have before doing anything.

[plittle2005]

Your port engine is standard (CCW looking at flywheel) and the stbd is "counter-rotating" (CW from flywheel). Standard rotation has a timing chain cam drive, CR has a gear driven cam.

FWIW, Crusaders are 4-bolt main bearings (truck engine) but Mercruisers are 2-bolt.

I have the same boat, and the biggest challenge would be getting the engine out. I always thought that the easiest way would be to disassemble it in place and remove the parts thru the aft salon door. But that would mean reassembling the new engine in place. Please let us know your progress on this, it will be very interesting and informative, for all of us who haven't had to do it yet!

Phil Little
'92 3307 AC

[Viper]

QR_BBPOST

QR_BBPOST The first thing you need to find out is if that engine is a counter-rotator or not.

OK if it is what would the difference be?

Typically the cam, crank seals depending on vintage/model, distributor, pistons might be installed 180* to standard rotation, starter too but you'll be able to use your current one if it's the same block.

If you go with an automotive engine, you'll want to change a couple of things to marine grade like the frost plugs, circ pump, and use your current peripherals like the starter, alternator, etc. as they'll be ignition proof.

[buster53]

QR_BBPOST Your port engine is standard (CCW looking at flywheel) and the stbd is "counter-rotating" (CW from flywheel). Standard rotation has a timing chain cam drive, CR has a gear driven cam.


Phil Little
'92 3307 AC

You are assuming the engines are original. Just maybe they aren’t. I have a 2001, 356, that does not have original engines.

[tomschauer]

my 2 cents...
If it froze and cracked the block, I would not even consider welding. Even if you are successful welding the cast iron block, there is a good possibility you have internal water jacket cracks as well that you could not get to too weld.
Sometime in the late 80's early 90's the manufacturers smartened up and started to use all standard rotation engines and used the outdrives or the Transmissons to provide the counter rotation. So as others have mentioned, verify your rotation.
Crusader, Mercury etc, did not build these engines. They are all from GM, and then "marinized" by crusader, merc etc. so yes you can use a gm 454 block.
As far as the 2 or 4 bolt mains, either is fine for your application, unless you plan to add forced induction and crack 600 or so horsepower.
GM used 4 bolt mains in engines with cast crank shafts and two bolts with steel crankshafts. for high performance I would rather have 2 bolts and steel crank, but for a cruising boat, either is just fine.

[RobGunn]

By nature I always think cheap and easy first. I would clean up the crack with a Dremel tool then pack it with JB Weld. Its a fast cheap try. If it works then GREAT! If it doesn't work then your only out a few $ and a couple hours... Then you look at the harder more expensive options.