Marine 427 SO Blocks?

[quebow03]

Well I have read a few things here and there from different thread regarding marine 427s. I have my eye on one or two and would like to know what could potentially go wrong using this block (assuming it was a closed system w/o salt water exposure). I have also read about how dual powered boats have both the engines turning in opposite directions. Sorry for the ignorance, but which direction should I be looking for (as I'm standing in front of the engine)? And finally has anyone actually used one of these block and/or made the necessary corrections to the cam and crank on the reverse engine? I would much rather not waste my time taking it completely apart in the bottom of boat only to find out it really isn't going to work. What should I be expecting to pay for a 427 SO block worthy of rebuilding??? Thanks

Dan

[Loadco]

The only difference you need to be concerned about is the crank (you would not use the cam). The opposite rotation cranks have the groves that move oil away from the rear main going in the opposite direction. They need to be polished off to a smooth surface. I have used both cranks without any problems.

In most cases the marine blocks are a good choice. Most have never been bored and have plenty of deck height.
You can even have them drilled and converted into a true side oiler if you want.

Standing in front of the engine the standard rotation goes clockwise.

You can always build a stroker and not use the 427 crank.

[mickmate]

Excellent info! I would like to add that boat motors don't suck road dirt and usually that is reflected in the size and condition of the bore. Another point is that boat motors don't get used on 3 minute rides to the store so it's the ultimate in "highway" miles without heat cycling the heck out of the block. If you use the crank on a reverse rotation motor with the grooves, it spits oil out the rear seal instead of pushing it back in. If you can get the heads off and get a bender light into the block you will get a real good idea of the elements it has been exposed to. Obviously the real test is sonic (after you've dragged it out of the boat). Boats are one of the few places to find undiscovered treasure with FE's. A good deal would be about 2K for a useable block, crank, caps and matched spacers combo. Good hunting!