Marineazing a chevy 262 block?

Aurel · Aurel's Garage

Hi all,

Since my winterization disaster on my boat (details), and since the succesful rebuild of my 3.0SC motor (details), I am toying with the idea of buying a good used chevy 4.3L V6 aka 262, and using all the marine parts that I have on my original seized motor, to rebuild a marine engine for my boat.

Does it sound feasible? I assume that the blocks are the same for marine or automotive, but this may be a wrong assumption. Does anybody know about this?

Aurel

VINMAN · 06-16-2008, 09:25 AM

The blocks are the same. Only difference is freeze-out plug material. You should have no problem.

cgarr · cgarr's Garage

Does it turn the same way? I once put a Mercruiser 6 cylinder in my car and had to change the cam and starter to turn the other direction.

dhoward · dhoward's Garage

Like Vin says, you don't want the possibility of a bad freeze plug sinking your boat.
Rotation is the other issue.
Things like starters and alternators need to be ignition-proof so as not to ignite fuel vapors in the engine space.

Aurel · Aurel's Garage

I have all the parts (starter, alternator, admission, exhaust, manifolds...from my old motor). Rotation could be a problem, but is that true? Why would marine engine rotate the other way? It seems so much simpler to change the rotation from the gearing if need be...

Aurel

Mule · 06-16-2008, 10:32 AM

Rotation is just the cam.

Shawn 357 · 06-16-2008, 11:11 AM

When I raced a car with an iron duke in it (GM 4cyl) there were a lot of different parts for the engines built for commercial or marine applications. The only reason I even bring it up is because some of the different parts were crank shafts, connecting rods, and other parts that you couldn't see from the outside. You may want to see what info you can find on the web before you start turning wrenches although most likely the long blocks are identical.

trekkor · 06-16-2008, 11:24 AM

I put a Corvette motor in my boat to replace the Volvo/GM 302 V8 that rusted/seized.

Use a fresh water cooling system. Uses anti-freeze, a heat exchanger and two water pumps.

I heard marine head gaskets are different than automotive ones to stand up to sea water.

KT

dhoward · dhoward's Garage

Some mfgrs used counter-rotating engines in twin applications. Some just turned the wrong way.

Chrysler comes to mind, but yeah, like Mule says, it's in the cam. You probably want a marine application cam anyway, to make power in the most useable spot for your application anyway.

Tim Hancock · 06-16-2008, 12:50 PM

As a teen, I bought and an old boat and the "Gray Marine" engine did turn backwards from a car engine....IIRC the Gray was an AMC 304 or something like that except for the reverse rotation.

trekkor · 06-16-2008, 12:57 PM

If it does rotate the 'wrong way', why not just use a RH or LH prop as needed?

KT

Aurel · Aurel's Garage

I may be able to reuse my original cams if they are not too rusted...

Aurel

Tim Hancock · 06-16-2008, 01:38 PM

Quote:

Originally Posted by Aurel

I may be able to reuse my original cams if they are not too rusted...

Aurel

It has been a long time, but IIRC, the distributor and it's drive gear need swapped also.

VINMAN · 06-16-2008, 03:14 PM

If its a Mercruiser or any modern late model stern drive,its 99.9% likely to be standard rotation. Nowadays the newer boats with twins use the drives to change prop rotation. Most of the time it was twin straight inboards that used counter rotating engines. Or a boat with a V-drive system.
All your existing parts can be swapped over( as long as they are still good).

Let me know if I can be any help. I'm not to far from you.