Merc or GM? Someone is sticking it to me

[wire2]

I left the transom project for a while to assemble the alpha gen 2 drive coupling and bell housing on my '84 5.7 (OMC) engine. The outside diameter of the flywheel is 12?", the bolt circle on the coupling is 12?". I have 6 sets of tapped holes in the flywheel at 11?"

What gives?

Did GM change to a larger flywheel since '84? And move the starter farther out on the block?
Or is the Merc flywheel and starter position unique?

So far I'm considering centering the coupling on the flywheel, transfer punch and drill new holes, then trim the "wings" off flush.

 

[Don S]

Re: Merc or GM? Someone is sticking it to me

Did GM change to a larger flywheel since '84? And move the starter farther out on the block?

They sure did, they have a 14" flywheel starting in 85

 

[wire2]

Re: Merc or GM? Someone is sticking it to me

Ok, thanks, Don. I guess that means I have to go the drill/cut route.

At least the bell housing fits. Sort of.
The dowel pins are too small, I have to make bushings.

 

[Don S]

Re: Merc or GM? Someone is sticking it to me

There is no way in HeII you are going to redrill that coupler and make it fit within a couple thousands of an inch. Get the right coupler for the smaller flywheel, I'm sure they will exchange an unused coupler once you explain what happened.............. Unless you bought online at the cheapest price.

At least the bell housing fits. Sort of.
The dowel pins are too small, I have to make bushings.

What kind of a mix and match mess are you building? OMC, Mercruiser, Gen II, Gen I, Dowel Pins?????????