Marine 350

[Sammy]

What is the difference between a 350 made for a boat & what we have in our trucks? Has anyone put one in a truck? Do they have all the provisions a standard 350 would have such as water pump , Pwr steering etc? I may have a deal on one it is a 4 bolt main but need to know if I'm barking up the wrong tree. Thanks.

[cooters]

marine blocks generally have thicker cylinders but otherwise i know of no other differences. The newer ones are vortec longblocks with carbs.

[special-K]

They still run alternators and the heads will be the same castings.

[JAKES 68GMC]

My dad bought a new Mercruiser 350 for his first lobsterboat back in 94-95. A guy at the dealer where he bought the motor told him the Mercruiser 350's had heavier block castings, a forged crank, and 4 bolt mains.

The boat went 35mph with the 350. It was a 22 foot boat with an outdrive on it.

[roughedup72]

You may have to add some brackets and you will have to change the exhaust manifolds but it will bolt right in.My brother just did the same thing to his 88 2500 4x4, the only thing we noticed is that it seems like the cam is different. The cams in marine engines seem to make more torque at low rpms and the hp dont seem as great as the truck and car engines do. but nonetheless it will work.

[Wootdog]

My next door neighbor has one. the big difference for those motors is that they don't have regular bolt ons. IE the starter and alternator are such that sort. To limit sparks as in being able to start a fire. My two cents.

[special-K]

You can buy a long block and just bolt your automotive stuff on.Basically,marine-duty = heavy duty.I have a marine 6.5 turbo diesel in my`92 K3500 work truck,higher nickle content wider/beefier main webs.I got injector pump/turbo,and heavy cooling marine set-up,too.It makes 300hp vs 195 stock.The medium-duty turbo is non-wastegated (marine runs steady rpms)and the injector pump is mechanical with bigger head and rotor.All it needs is 12-volt wire to I/P,no electronics.

[Sammy]

So what I see so far, possibly problems connecting assy such as starter, Alt, pwr str pump. Maybe a serptine setup would solve that issue. And the starter & flywheel? I wouldn't have thought that GM would change the design on bolt patterns, just don't see it. As far as the thicker cylinder walls maybe. This is a long block 350 no intake. Curious if a carb & intake will bolt up too. Then worried about manifolds. This motor wasn't a vortex it was an older model. Thanks for everyones input. Guess I wonder if you were to rebuild it would you take the chance for $100.

[wibilly]

he77 yea as stated before blocks are better and all internals these things were built to run 5000 rpms all day long! the cam grinds are not well suited for street use but will work

[metalmassfab]

If the marine engine was used in saltwater, stay away from it. Most all marines engines use whatever body of water the boat as its coolant. A block that has had saltwater running through it is bad news. Not much you can do with one, boil it out, bake it, freeze it, the rust will keep happening. Aluminum manifolds, radiators, etc. will feel the effects much sooner as well. My father has been a commercial fisherman (among other things) for over 30 years. We've seen countless times when someone 'scores' on a marine engine, and bad things soon follow. The higher nickel content, thick walls and such are because of the corrosive environment the engines live in. A little more nickel = a little slower to rust, a little thicker walls = they can rust a little longer before death. Electrolysis is bad news...

[special-K]

Good point.Our used inboards around here are mostly saltwater tubs.I was thinking new stuff.That`s what I got.