Please help identifying which stern drive I have

[dwojo]

I have a 1979 Mercruiser 260. I was wondering if someone could please help me to identify which model stern drive I have? On the case, it says Alpha One, but in the manual it has no Alpha One(unless Alpha One is what's referred to as Model I in the manual...and if so, how do you tell the difference between early model I and late model I?). I am looking through the Clymer's manual for Mercruiser stern drives from 1964 to 1985, and I am baffled that I am having such a difficult time figuring which one I have.<br /><br />Thanks for any help you can give me!

 

[Bondo]

Re: Please help identifying which stern drive I have

Someone May have up-dated the drive, they are very interchangeable....<br />Alpha1's have a Flat top cap....And a Squareish trailing edge on the anti-cavatation plate..<br />Mod.1's have a lifting eye in the top cap....And a roundish trailing edge on the cav-plate...

 

[llerrad]

Re: Please help identifying which stern drive I have

Take a look at www.mercstuff.com on this site there is a section, how do I, then check which unit do I have. You will have all the pics you need. I bet for the year, you have a pre-alph or<br />"R" unit.

 

[dwojo]

Re: Please help identifying which stern drive I have

Thanks for the tips. I've determined that it is an Alpha One, and now I'm trying to decide where the drain and vent plugs are for the gearcase lube. The drain plug is self-explanatory, put I am unsure which one is the fill plug. One the right side up top is a plug that you would take off with a 3/8" or 1/2" drive, and on the left side up top is another plug that you would take off with a flat head screwdriver. Which one is the vent plug? <br /><br />Also, is there any reason to take the square cap with the four bolts off?<br /><br />Thanks again!

 

[llerrad]

Re: Please help identifying which stern drive I have

Screw driver plug is the one and don't take off the cap with the four bolts. Keep checking the site mercstuff it will also give tune up tips.