Are Merc Mc-1 and Alpha 1 Gen 1 interchangeable ??

[moonrakercat]

Long story short - I have a 1979 thundercraft with a 305 merc and mc-1 outdrive. Outdrive lost it's top gears late this year - so I need to put on another drive. I've decided to find a complete unit upper & lower. (I'm in Ontario Canada)
I've considered going to Luken - 1750 cdn + tx for a reman & repainted mc-1 drive with a new h2o pump , but also kept an eye on Kijiji and facebook marketplace for an mc-1 drive - there are quite a few out there - $ 250 - 750 - but most are for 4 or 6 cylinder engines - and some of those drives are badly corroded - as was my old drive that bit the dust.

I've found an older mc-1 drive for 600 - fair shape but it needs some paint and has holes in it from one of those big fins that used to be on it - it will prob need a new h20 pump too. I really don't want to paint my drive - I know painting & prepping a merc drive is a pain in the *** if you want it to last.

I'm also seeing quite a few alpha 1 drives out there - I've heard that the gen 1 are interchangeable with the mc-1's - and I've had another person tell me that I will have to change the drive shaft on it - so I'd like to find out if anyone here knows if the 2 are interchangeable ? or if I would have to do anything like swap the drive shaft ??

I'm new to outdrive mech work and have decided to do the swap myself after the marina I was dealing with did a crap job taking my outdrive off - damaged my boat & dinged the prop badly. I know the shifter needs to be in the forward position - and I have new gaskets for the outdrive - and know that it would be good to build some sort of outdrive support if I plan to start to do my own maintenance on it - which I do.

I'm not quite sure what to do drivewise on a used or rebuilt - any advice is appreciated.

 

[Scott06]

Long story short - I have a 1979 thundercraft with a 305 merc and mc-1 outdrive. Outdrive lost it's top gears late this year - so I need to put on another drive. I've decided to find a complete unit upper & lower. (I'm in Ontario Canada)
I've considered going to Luken - 1750 cdn + tx for a reman & repainted mc-1 drive with a new h2o pump , but also kept an eye on Kijiji and facebook marketplace for an mc-1 drive - there are quite a few out there - $ 250 - 750 - but most are for 4 or 6 cylinder engines - and some of those drives are badly corroded - as was my old drive that bit the dust.

I've found an older mc-1 drive for 600 - fair shape but it needs some paint and has holes in it from one of those big fins that used to be on it - it will prob need a new h20 pump too. I really don't want to paint my drive - I know painting & prepping a merc drive is a pain in the *** if you want it to last.

I'm also seeing quite a few alpha 1 drives out there - I've heard that the gen 1 are interchangeable with the mc-1's - and I've had another person tell me that I will have to change the drive shaft on it - so I'd like to find out if anyone here knows if the 2 are interchangeable ? or if I would have to do anything like swap the drive shaft ??

I'm new to outdrive mech work and have decided to do the swap myself after the marina I was dealing with did a crap job taking my outdrive off - damaged my boat & dinged the prop badly. I know the shifter needs to be in the forward position - and I have new gaskets for the outdrive - and know that it would be good to build some sort of outdrive support if I plan to start to do my own maintenance on it - which I do.

I'm not quite sure what to do drivewise on a used or rebuilt - any advice is appreciated.

Yes an Alpha one gen one will swap with a MC1 drive. Should be plug and play. Also the alpha drives will be about 10 + years newer than your MC1 drive

The driveshaft comment you are hearing is related to inline engines used a shorter driveshaft where it engages the coupler. Shouldnt be an issue in your case but if you there was an issue you can swap in the original one you have just at the first Ujoint (MOOG 315G or equivalent )

 

[Bondo]

Ayuh,..... In addition to what Scott says, ya gotta use a drive for a V-8,.....
The I-4, 'n V-6 drives will be geared too low,....

 

[moonrakercat]

Ayuh,..... In addition to what Scott says, ya gotta use a drive for a V-8,.....
The I-4, 'n V-6 drives will be geared too low,....

Yep - your right there - a 1.5 ratio - found that out early....

 

[achris]

If you have the opportunity, get a donor boat with a Gen II setup, maybe that has cracked the engine block, and swap the whole lot into your boat (using your engine). There's a bit of work involved in changing the engine over to GenII, but given time and patience, I believe it would be well worth the effort.

Chris.......

 

[moonrakercat]

If you have the opportunity, get a donor boat with a Gen II setup, maybe that has cracked the engine block, and swap the whole lot into your boat (using your engine). There's a bit of work involved in changing the engine over to GenII, but given time and patience, I believe it would be well worth the effort.

Chris.......

Hi Chris - if I was retired & had the time - I might try it - but for now I'm just learning - and don't know much about the gen ii - other than more expensive. Heck - I know little about the mc-1 and alpha i. Right now I would just like to get my boat up & running. Thanks for the suggestion though.

 

[peters715]

The trick is to determine if the 65532 is interchangeable with the 45514 unit. It looks the same.

I'll have to take detailed photos of mine an compare to these 65532 versions.