87 alpha 1 drive fit on my 78?? help help help

[1978 century]

i have a 1978 3.0 merc....i need a lower unit and i found a good alpha 1 drive unit from a 1987 ... will it fit my 1978 3.0 ????? this is the site its on its pretty cheap i wanna buy it but i need to know if it will fit

http://cgi.ebay.com/ebaymotors/ws/e...m=190072677045&ssPageName=STRK:MEWA:IT&ih=009

 

[Don S]

Re: 87 alpha 1 drive fit on my 78?? help help help

Without knowing the serial number of your drive, it's hard to say for sure just by looking. Measure center to center on the upper 2 studs on the pivot housing. If they are 4-15/16", the Alpha won't fit. The Alpha has a 5-1/16 dimension.
That is just the one way to distinguish the differene without being able to see both and compare.
Before you ask, NO, grinding the holes in the drive so they will fit will not work. There are other differences.

 

[1978 century]

Re: 87 alpha 1 drive fit on my 78?? help help help

lol i would never grind them .. i dont half a$$ any thing...thanks for the info... so if the bolt pattern is correct then it will work? and if it wont will the bottom half of the alpha bolt on to my upper half??

 

[1978 century]

Re: 87 alpha 1 drive fit on my 78?? help help help

its the 4 15/16 so will the alpha bottom work with the top of mine

 

[Don S]

Re: 87 alpha 1 drive fit on my 78?? help help help

Don't know. Never tried to put a One Drive upper on an Alpha Lower.
But I seriously doubt if they would work together. The next step newer from the One drive, was the R. (short for Redesigned) a few years later it went to MR (Mercruiser Redesign) a few years of the MR, and they changed to the Alpha I you see on ebay.