73/74 Mercury 20hp

[bjarnold1]

I bought a 1973 20hp awile back to use on my 16ft Bass Tracker duck boat with a 20" transom. The motor is a long shaft and has spark but the lower end is shot due to saltwater. I recently picked up a 74 20hp short shaft to use as a parts motor however it is like new and starts easily after I had cleaned the carburetor. What would be involved in switching the powerheads or would the short shaft motor work on my boat?

Thanks

 

[Mi duckdown]

Re: 73/74 Mercury 20hp

A short shaft will not work on a 20" transom. By swapping the power head You still have a junk lower end. Now, the the lower end from the short shaft can be used (assuming the gear ratio is the same), but you will have to swap out the drive shaft, water tube and shift shaft, from the long shaft.
Does this make sense to you?