Alpha Differences...

[harbormaster]

For you Mercruiser experts out there....
What difference are there on the Alpha 1 outdrives built before 1992 and those built from 1992 on. I have heard the ones built in 1992 and after referred to as Alpha 2. Thr reason i am asking is that I have a shop manual for Alphas up to 1993 and was wondering if I could use it for my 1995 model alpha.

[AVickers]

Funny you should ask...

I was in League City last week to look at and discuss with a guy a Bravo Conversion for my C22. He suggested that I change out the Alpha 1 to an Alpha Gen2 and ran through some of the differences. Less money, less trouble and a stronger drive??? And a relatively easy conversion.

The Alpha I and the Alpha Gen 2 are different from each other (supposedly, the Gen2 is beefier), but there are a lot of similarities. And although almost no parts interchange, they all look about the same and service procedures would be similar. As I understand it, one critical difference is the water pump -- which is a part you can service yourself w/ few tools.

My guess is that you can figure it out using the old service manual on your new drive.

[Rootsy]

the water pumps are significantly different... not so much in function but in design and parts.. the GEN II impeller is miles ahead of the original Alpha drive... the transom assy's are different as well as some of the ergonomics of the drive but the overall function and design remains the same... i don't have exact details as far as gears, shafts, seals and clutch dogs etc, i havnt had one apart in a number of years and very limited experience with the GEN II in that department...

honestly, unless you are really familiar with em and have all kinds of special mercruiser service tools you are pretty limited to vacuum / pressure checking the seals, replacing the impeller, greasing the transom assy and replacing the gimble bearing as well as replacing the gear oil...

[harbormaster]

Is there an easy way to tell the GEN I and Gen II apart?

[oldLenny]

http://www.sterndrives.com/bulletins/mc/97/EN_004.PDF

[Eddie1823]

The easy way to tell the differance is to look in the engine compartment for an on board gear oil resevoir. All the Gen 2's have the thru transom plate oil passage like the newer Bravo's. If the drive is off the boat, looking at the front of the drive, driveshaft end, there will be a small spring loaded check ball on the upper left hand side inline with the mounting bolt holes. Gen 1 drives don't have this oil passage and if they do have an onboard oil resevoir it will be connected to the upper vent screw hole with an external SS hose and drilled thru transom.

[ZF-Mac]

Gen II Drives have bolt heads accessible from the upper to split the drive. Alpha one's have studs and nuts accesible from the lower end. Upper gear sets are the same less the short vertical shaft. It is rifle drilled for lube... Lower shift assem. is differant not sure about the gears...

mac

[MOP]

Just a thought, shimming specs may be different between the two drives. Try to get your hands on the specs from a late book just for safety sake.