OMC 3.0 Engine Swap

[goaliesmh]

I replaced an OMC 1985 3.0 Liter GM engine with a brand new engine. All parts swapped out beautifully except for the flywheel and the coupler. New engine was a two piece rear seal original engine was a one piece. I got a new flywheel from the engine supplier but was told to go to a machine shop for a coupler to fit. I went to a local machine shop but they asked for specs. I paid almost $2500.00 for the engine and associated parts and now I am screwed. Is there anyone out there that knows where I can find a coupler for a two piece rear main seal? It is a stringer 1985 OMC outdrive. HELP!!!!

 

[Bondo]

Re: OMC 3.0 Engine Swap

New engine was a two piece rear seal original engine was a one piece.

Ayuh,..... Are you Sure,..?? That sounds Backwads.....

I went to a local machine shop but they asked for specs.

Those "Spec's" would be the Bolt Pattern,+ Fitment to the Flywheel that you're using....

 

[goaliesmh]

Re: OMC 3.0 Engine Swap

So far everything I have attempted seems to be backwards. So short of changing the crankshaft I am screwed.

 

[Bondo]

Re: OMC 3.0 Engine Swap

Nope,... Not at all....

Bring the New Flywheel,+ the Coupler back to the Machine Shop,+ have them cut it down,+ redrill the holes to match the Flywheel....
Or,....
The 2 piece crankshaft bolt pattern is/ was the Standard configuration for your boat originally,...
So,...
A Standard Coupler for your boat should Bolt Right Up....

The 2 piece crankshaft bolt pattern should be on a 3, 1/4" pattern,+ the 1 piece seal crankshaft will be on 3"....

Btw,.... You Can't change the Crankshaft,... It's the Block that's Different....

 

[goaliesmh]

Re: OMC 3.0 Engine Swap

I think it is the other way around the split is smaller bolt pattern is narrower but the result is the same.I need the part machined. No one out there sells one?

 

[Bondo]

Re: OMC 3.0 Engine Swap

Ayuh,....

That's Why I said before,.... You've got it Backwards.....

The 2 piec rear main seal uses the Larger bot pattern,+ the 1 piece the Smaller......

Btw,....
OMC went out of business about the time Chevy changed the bolt pattern,..
There for,... They never used the smaller patterned coupler....