Difference between OMC and Chevy 350?

[RTFA]

I recently purchased an 87 Wellcraft 24 footer with a bad engine, Has an OMC 350 with a Cobra outdrive. Got her for a song and all she needs is a motor, outdrive was rebuilt less than six months ago. Any who, been doing some research on Ebay and such for a replacement "marine" engine. Other than the exhaust manifolds what , if any, is the difference between a regular 350 engine say out of a Chevy pickup versus a 350 marine engine?

I mean could I use a motor from say a wrecked chevy truck of about the same year with only 30,000 or so miles on it? I think you see where I am going with this?

 

[Bondo]

Re: Difference between OMC and Chevy 350?

Ayuh,.....

If you find the Right Vintage,..... Sure It'll Work......

 

[Don S]

Re: Difference between OMC and Chevy 350?

The engine will work, but you would still need to use things like the Marine starter, Marine alternator, Marine Distributor, marine fuel pump, marine carb, and if it's raw water cooled, you will need brass core plugs and marine circulation pump.

 

[Dakota47]

Re: Difference between OMC and Chevy 350?

yep,, take all the marine stuff off old motor

 

[jomamma1]

Re: Difference between OMC and Chevy 350?

If your motor has a inclosed cooling system, the only internal parts that are different and need to be swapped are the cam shaft, oil splash pan. Then just swap all your marine externals and away you go. If yours is raw water cooled than there is more to think about. JG

 

[Coors]

Re: Difference between OMC and Chevy 350?

The marine oil pan holds one more quart.

 

[RTFA]

Re: Difference between OMC and Chevy 350?

If your motor has a inclosed cooling system, the only internal parts that are different and need to be swapped are the cam shaft, oil splash pan. Then just swap all your marine externals and away you go. If yours is raw water cooled than there is more to think about. JG

Raw water cooled.... What more to think about?

 

[whywhyzed]

Re: Difference between OMC and Chevy 350?

......

 

[Mkos1980]

Re: Difference between OMC and Chevy 350?

You can probebly keep the cam. If its out of a truck its going to be pretty mild. I wouldnt be surprised if the stock flat merc cam was more agressive.

 

[zvolv]

Re: Difference between OMC and Chevy 350?

Brass freeze plugs are a good idea, especially for raw water cooled. The intake manifold has a brass liner for the coolant passages too.

Its worth researching compression ratio and cylinder head design too. I know for example in the Volvo DOHC boat engine the cylinder head has a different size and shape combustion chamber than its auto counterparts. Thats volvo though.

Dont even think about running the auto starter, distributor, or alternator unless you want to run the risk of blowing up.

 

[Peter Eikenberry]

Re: Difference between OMC and Chevy 350?

Take a course. Marine Engines 101. http://newboatbuilders.com/pages/fuel-2.html

 

[RTFA]

Re: Difference between OMC and Chevy 350?

Thanks for all the help guys, real nice folks on here.

 

[jerryjerry05]

Re: Difference between OMC and Chevy 350?

If your running it in freshwater the only thing you need to make sure is that the flywheel bolts up. Then use all the marine components:starter,alt,fuel pump. If it's salt water then a whole lot more.Jerry