1978 omc 140 3.0 engine (chevy 4cyl.)

big_daddy72

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It has thrown a main bearing and am looking for a kit to rebuild the engine. Were is a good place to find what I need. I there a place to get a kit like they sell for auto engines?
 

Kainon

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

Yes, you can get engine main and conn-rod bearings from many marine engine rebuilder, maybe even this site. try google.com and type, Marine engines, hit search.
 

zbnutcase

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

It has thrown a main bearing and am looking for a kit to rebuild the engine. Were is a good place to find what I need. I there a place to get a kit like they sell for auto engines?

Have never seen a rebuild kit for these engines; marine market so small I doubt they even exist, however, most good auto part stores can get what you need.
 

Kainon

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big_daddy72

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

Have never seen a rebuild kit for these engines; marine market so small I doubt they even exist, however, most good auto part stores can get what you need.

Do you know were to get the engine specs. The marine version is 3.0 but chevy didn't have a 3.0 liter in '78 they had a 2.5 liter (both same block) So I am assuming it has been bored among other things to make it a 3.0. If I had that info I could get the kit from an auto parts store.
 

spect8r

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

The only difference is the head that was used.
 

Bondo

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

The marine version is 3.0 but chevy didn't have a 3.0 liter in '78 they had a 2.5 liter (both same block)

Ayuh,... The 3.0l has a Longer Stroke,+ Bigger Bore...
The 2.5l used in Chevy/ GM cars is NOT the same motor, nor the Same Block....
The 2.5l,+ the 3.0l used in boats, is only a Marine/ Industrial motor...
 

fat fanny

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

I believe that Napa has a wire aray of rebuid parts for the 4cyl. try thier marine catalog. My Napa gave me a catalog try your local store and they usually are more than helpfull.
 

hpdon

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

rebuilt my 3 litre over the winter 30th over speed pro flat top pistons , bought from summit racing felpro # 17000 head gasket rod bearings are your std. gm 350 mains are same .you might have to have your crank turned or polished. good luck
 

CobiaXL

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Re: 1978 omc 140 3.0 engine (chevy 4cyl.)

I know its a lil late but Ive used rpmmachine dot com and am very pleased....
 
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