Drive Shaft Question

[chimo1966]

Is a drive shaft assembly from a Pre Alpha lower unit interchangeable with a Alpha one lower unit ?

 

[Don S]

Re: Drive Shaft Question

How far "Pre-Alpha" are you talking about. <br />To me, Pre-Alpha is anything Mercruiser had from the 60's to when they named them Alpha, in the early 80's.<br />If you are talking about an R, or an MR, then some of them are the same. There are 2 different lengths.

 

[chimo1966]

Re: Drive Shaft Question

Don:<br /><br />The boat was made in 1980 however the drive shaft has the vertical preload pin, Is the only difference in the lenghts of the shaft ? my old lower unit below the water pump is smooth were my new lower unit has treads. Will my old drive shaft still work in the new lower unit ?

 

[Don S]

Re: Drive Shaft Question

You are talking about a different drive shaft than I was.<br />The lower units are interchangeable with the upper from the older style to the newer, but you can't change parts from one lower to another. The one with out threads is either a 1 drive or an R. The MR and newer had the internal nut that was used to hold the vertical shaft.

 

[chimo1966]

Re: Drive Shaft Question

Does that include the prop shaft and gears as well ?