MC2 what will replace it

[Tinmanoz]

Greetings
we had a 65 GM I/L 6, (sn # 1830279) and the stern drive needs to be replaced (sn# 1929008).
We got a remanufactured 250 GM I/L 6 that slid in perfect but the outdrive rebuild is undoable and we need to replace. SE 104 was close but they can not make it for us , the ratio didn’t work? pinion has 24 teeth ring gear has 22. Can anyone help us find an outdrive that will fit the new engine? Any help is greatly appreciated.

 

[Bondo]

Ayuh,..... Welcome Aboard,..... You'd have to update the transom assembly to update the drive,.....

 

[Tinmanoz]

Thanks Bondo, any brand easer to change the transom assembly with this MC drive, to minimize transom damage?

 

[achris]

I'm not sure why you're trying to keep a 56 year old power package going given the NLA status of most of the parts. The easier way would have been to swap the whole lot out for a late model V6, and it'll have been a lot less expense too...

However, if you still want to keep the inline 6, the way I'd do it is this...
1. Find a donor boat with a late model (1991 and later) 3 litre engine (preferably improperly winterized and cracked) and Alpha One gen II drive.
2. Use the starter motor, flywheel, engine coupler and flywheel housing from the 3 litre on the online 6.
3. Pull the old transom assembly out of the boat and put the gen II assembly in. This will involve a SMALL opening up of the hole in the transom.

This will involve a lot of work and a lot of 'test it and see' trialing to get it to work properly, but as so many of the parts for the current set up are completely unavailable, it may be your only option...

Chris....

 

[achris]

Thanks Bondo, any brand easer to change the transom assembly with this MC drive, to minimize transom damage?

Going to any other brands would involve a lot more 'transom damage' than staying with a MerCruiser package... The change in transom cutout from early MC1 to anything later doesn't involve much transom damage.. a slight opening up of the keyway cutout, and the relocation of one pair of stud holes.

Chris....

 

[Tinmanoz]

Thanks Chris
I may change my plan, seen an SE alpha 1 G2 transom housing for $1,800 & complete SE 116 outdrive for $1,700

 

[achris]

Thanks Chris
I may change my plan, seen an SE alpha 1 G2 transom housing for $1,800 & complete SE 116 outdrive for $1,700View attachment 347547
View attachment 347548

Nice, but you are aware that the old inline 6 won't just drop straight onto that inner transom plate. You'll still need to find a 3 litre engine of 1984 or later to rob for parts to make it work....

Chris...

 

[Tinmanoz]

Thanks again Chris
got a line on 91or 92 4 cylinder Alpha 1 gen 2 donor boat

 

[matt167]

There is a way to put an MC-1 on that early transom plate, but it doesn't work correctly.. My dad has it on his '66 Islander and it involves chaining the drive in place for reverse. It floats and fishes so he is happy, but it isn't for everyone

 

[Campfire]

Why not just buy a used pressure tested MC-1 drive? They are available.

 

[achris]

There is a way to put an MC-1 on that early transom plate, but it doesn't work correctly.. My dad has it on his '66 Islander and it involves chaining the drive in place for reverse. It floats and fishes so he is happy, but it isn't for everyone

That's because he doesn't have either a trim pump with internal valving, or a external 'reverse lock valve'..

 

[matt167]

That's because he doesn't have either a trim pump with internal valving, or a external 'reverse lock valve'..

Yup

 

[Scott Danforth]

I would look for a 1996 or later bayliner with a rotten hull with a 4.3 and Alpha drive and transfer the whole works like post #4

then you sell the trailer the bayliner was on, sell the glass, etc and the whole thing may cost you sweat and about $1000

 

[Tinmanoz]

WOW what a site some much information here, thanks everyone


lee

 

[matt167]

WOW what a site some much information here, thanks everyone


lee

The cool thing with Mercruiser is they never changed the transom keyhole very much, so a transom assembly from 2021 can fit a mercruiser powered boat from 1965. There is some minor trimming involved but for the most part, the keyhole design is the same... OMC Cobra and Volvo are also similar, although going OMC would be a mistake

 

[achris]

... although going OMC would be a mistake

Fortunately that's a mistake that would be difficult to make now. OMC Stern drives stopped production in the 90s, and finding a new one now would be near impossible.

 

[matt167]

Fortunately that's a mistake that would be difficult to make now. OMC Stern drives stopped production in the 90s, and finding a new one now would be near impossible.

Not on a rotted 80's Bayliner that litter places everywhere.. Not new, but it could be tempting with a newer drive for free or so