Pre-alpha swap

swat

Recruit
Joined
Sep 13, 2010
Messages
4
Greeting all!
I am not new to boating but I am new to big water boating. I reciently purchased a cabin cruiser for fishing the great lakes. The boat surveyed out just fine. However in the survey the out drive was called a alpha-1 and the previous owner stated it was a alpha-1. The reason i looked into it was the previous owner said that the out drive was geared down to attain slower trolling speeds of 1-2 mph. The gear change made planing the boat a issue.

I was thinking about changing the gearing back. I tried to find serial numbers off the out drive and cant find anything due to the corrison. The anodes are pitted pretty bad.

Now to my question....

Does anyone know of a drive that I can replace the pre-alpha with, without re-working the transom, maybe a updated bolt on replacement type thing?

Motor's a 1982 260 mercruiser.

Thanks for any info you may have in advance!!
 

cr2k

Captain
Joined
Mar 19, 2009
Messages
3,730
Re: Pre-alpha swap

If it is an Alpha you can switch with any alpha (not Alpha 2), just make sure you get the correct gearing for your needs. I believe even some of the early drives will work too the R and MR.

What you need to look for is the input shaft has to be the same length.
 
Joined
Mar 27, 2010
Messages
3,028
Re: Pre-alpha swap

Here is a chart for the ratio on different engines. The universal joint yoke should be stamped somewhere with a letter which indicates also which ratio is in the drive. (Unless someone has changed it).
 

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Glastron_V210

Petty Officer 1st Class
Joined
Jan 28, 2009
Messages
324
Re: Pre-alpha swap

I have an alpha (Not gen 2 alpha) in place of my pre-alpha drive.

The input shafts were different lengths for V8 and nonV8 applications. This is because the engine couplers were different.

If you find a drive in good shape, you can have the gear ratio changed. Also, you can swap the input shaft and do universalls at the same time.

Chay
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,357
Re: Pre-alpha swap

Does anyone know of a drive that I can replace the pre-alpha with, without re-working the transom, maybe a updated bolt on replacement type thing?

Motor's a 1982 260 mercruiser.

Ayuh,.... A brand new SEI Alpha 1 drive from right here at iboats is a Plug, 'n Play drive for your ship...;)
 

ingalp01

Petty Officer 1st Class
Joined
Sep 11, 2010
Messages
357
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