1986 mercruiser 260 350, what drive?

[samm835]

I have a 1986 merc 260 in my Sea Ray 268. I'm not sure what drive I have. Is there anyway to know before I pull the boat out? If the engine serial number helps it's 6817129.

 

[Bt Doctur]

Most likely a Alpha1 1.50 ratio ,double check the serial number. should be a letter too

 

[samm835]

Thanks Doc, is there a test that can be done on a heat exchanger to make sure its working like it should?

 

[Bt Doctur]

put air pressure in the raw or fresh water side of it and see if it holds

 

[Pete104]

It might be 1.5:1 but also may be a 1.32:1. The heavy duty gear set for big single engine boats.

 

[samm835]

Thanks Pete & doc, I didn't realize the alphaone was made in 1986, I thought (my ignorance) the alphaone was a newer type drive.

 

[Bondo]

I didn't realize the alphaone was made in 1986, I thought (my ignorance) the alphaone was a newer type drive.

Ayuh,.... The Alpha 1 came out in '83, the Gen.IIs in '91,.....