Long or Short Shaft ?

[RangerJim]

How do I figure out if my little Glastron needs a long or short shaft ? I have a Evinrude 33hp Ski-Twin Long Shaft on it now but I think I can go short shaft, I know I can if I put a jack plate on it but if I don't install a plate what is the height that the transom needs to be ?

 

[jdsgrog]

Re: Long or Short Shaft ?

A short shaft motor is 15 inches. The transom is 15 vertical inches. The actual transom may be an inch or two larger since it is on an angle.

 

[RangerJim]

Re: Long or Short Shaft ?

So I went out and measured my transom, from top/center to bottom of the V it is about 20.5 inches. I measured my motor in the down position and the center of the prop shaft is a little over 8 inches below the bottom of the boat. I think I could run a short shaft, 3 inches below the transom should be fine for starts, I know i trim my race boat out to just about 1/2" below bottom of hull when at wot and trimmed.

 

[erikpn]

Re: Long or Short Shaft ?

So I went out and measured my transom, from top/center to bottom of the V it is about 20.5 inches. I measured my motor in the down position and the center of the prop shaft is a little over 8 inches below the bottom of the boat. I think I could run a short shaft, 3 inches below the transom should be fine for starts, I know i trim my race boat out to just about 1/2" below bottom of hull when at wot and trimmed.

It will cavitate badly. Do not run a short shaft. Why would you do that? Do you already have a short shaft and are trying to reason out an excuse not to get a long shaft?

 

[RangerJim]

Re: Long or Short Shaft ?

I have a long shaft, just looking to re-power with more HP or dual up with another 33hp Evinrude Ski-Twin, looking to save weight anywhere I can I guess. Thanks for the reply,