shaft too short

[brianprice]

I have a mid-70's 15 HP Johnson that runs fine, but it has a short shaft and the propeller doesnt sit low enough in the water, therefore not planing the boat. I have another motor with a longer shaft, but that one won't run like the other one. Other than cutting a wedge out of the boat and dropping the motor down (which I really don't want to do) what are my options?

 

[Hooty]

Re: shaft too short

Before I did anything, I'd be sure that the shaft was to short for sure. With the engine setting on the transom the cavitation plate should be about even with the bottom of the boat. If the cav plate is four or five inches above the bottom of the boat, it's too short.<br /><br />c/6<br />Hooty

 

[Solittle]

Re: shaft too short

Brian - You can convert from short to long & vice versa. You will need a shop manual, 5" housing extension, driveshaft, shift rod extension and water pick-up tube. I would look around for a junk engine and swap the necessary parts. The parts may not be that easy to find as this is a popular conversions as many of those 15s (and 9.9s)are desirable for use as sailboat auxiliaries.

 

[roscoe]

Re: shaft too short

Or advertise that you will trade engines with someone.

 

[brianprice]

Re: shaft too short

I have an old engine that isn't running right that is a long shaft...do I still need to find all of those parts to make the shift, or do you think that it is something that can be done if I already have both motors?

 

[Skyhigh]

Re: shaft too short

I heard that, you could buy a pill for that now. Suppose to make you shaft longer. LOL