Still confused about shaft length

[ovf]

Hi,<br /><br />I've searched the forum for information regarding shaft length and am unfortunetly still confused. The posts mention lengths of 15", 20", 25" and 30" but the transom on my boat is 22" from the top of the transom to the tip of the V. Is a 20" inch suitable for transom between 15" and 20" or between 20" and 25"?<br /><br />Thanks

 

[MIKE F]

Re: Still confused about shaft length

I believe, a 20" shaft length motor, would be too short, for your boat. You need a 25" shaft. Top of engine mount, does not have to sit, on the transom. My boat, has the top of the engine mount, 2 1/2-3" above the top, of my transom.

 

[Hooty]

Re: Still confused about shaft length

If you can run a 20" shaft engine on a 22" transom without ventilating the prop (cavitating), that's fine. <br /><br />c/6<br /><br />Hooty

 

[ovf]

Re: Still confused about shaft length

Thanks for the quick replies. How can I tell if running a 20" shaft will ventilate the prop.? All I've ever used on the boat is a 12V trolling motor.

 

[ob]

Re: Still confused about shaft length

Ovf, determine mount location and insure when mounted that cavitation plate on motor is roughly flush or slightly above mean bottom of boat.A water test will be required to determine final location of motor height for optimal performance.Choose a shaft length that when mounted will allow for transom bracket relocation to optional adj. holes.Proper location of motor will allow adj.of cavitation plate location About 2" above and below bottom of boat.

 

[MIKE F]

Re: Still confused about shaft length

ovf,<br />What boat do you have? If you've been using, a 12V trolling motor, I doubt you need that 25" shaft motor,that I mentioned earlier.

 

[JB]

Re: Still confused about shaft length

Howdy, OVF.<br /><br />Your transom is almost surely a 20".<br /><br />Correct measurement is a vertical line from the top of the transom to a point level with the keel. That point is usually several inches aft of the bottom of the transom.<br /><br />Good luck.

 

[Boatist]

Re: Still confused about shaft length

ovf<br />The 20 shaft will work fine on your boat. Your boat model number and spec will tell you shaft length. Most boat are either 15 inch (short shaft) or 20 inch (long shaft). The 25 inch (extra long shaft) in usually only for sail boats and mounted on a braket not an actual transom. Some larger boats will also use a 25 inch shaft as a kicker motor but the goal here is to keep the power head from going under the water when backing into a following sea.<br />My 14 foot Klamth with a short shaft actually messures 17 inches the way you messured yours. I mounted my 15 inch short shaft with a 3/4 board on top of the transom making my distance 17 and 3/4 inches and it works perfect. I did this for two reasons. One I use this boat in a lot of shallow water frogging and getting Clams. Two: I got a little more speed out of my 15 hp and had no cavition problems even in hard turns.<br />What you need is a 20 inch shaft but get your boats model number and look up the spec or go to the dealer you are going to buy from and ask him. What brand, size, boat do you have and what size motor are you looking at?

 

[ovf]

Re: Still confused about shaft length

Hi,<br /><br />Thanks again for the help everyone. Sorry about not posting the model information. It's a Tracker "Guide-V14' Utility" model 65613. The maximum hp rating is 10hp. It sounds like the motor I've been looking at will work but I'll re-check the measurement and see if the manufacture's web site has any information.