How to determine if a shaft length is right for your transom?

[Robbyracks]

Hey folks,

I bought what I think might be too long of a shaft for my aluminum boat. I would like to get someone to help me determine if the motor is actually too long or perhaps work with my current set up.
Firstly, what should I measure exactly? Should I start with the transom? Shaft length? Where should I measure from?

Thanks!

 

[racerone]

Post pictures of your motor.-----Or a model / serial #.------Measure the transom on your boat.----A 12' aluminum is usually a 15" transom.----A 14' boat can also be a 20" transom.-----Or run to your local friendly boat shop and they can tell in seconds whether you have the right motor.

 

[Robbyracks]

Here are some pictures:

 

[Robbyracks]

Any thoughts? Will this motor work? I suspect it's too long.

 

[909]

It looks too long.

Put it on the boat and take a picture.

The cavitation plate should be at the bottom of your boat.

 

[Robbyracks]

It looks too long.

Put it on the boat and take a picture.

The cavitation plate should be at the bottom of your boat.

I measured it again. Does look too long.. From keel to transom, 16". The shaft is 22" according to the method I used to measure. So off by 6".. I hesitate to put it on the boat now because I don't have anyone to give me a hand.. it's heavy!

 

[roscoe]

 

[racerone]

That motor is for a 20" high transom !

 

[tpenfield]

Yup . . . short shaft boat . . . long shaft motor. Not going to be the best thing.

 

[Robbyracks]

Yup, you're all correct! Unfortunately... I bought this hastily.. inexperience...

I've listed it again. The thing that bugs me is that the seller insisted it was a short shaft. She was an elderly lady. I guess there's a smaller market for long shafts because since I listed it two days ago not a single person has inquired. I suppose worse things can happen in life!

 

[tpenfield]

Yup, you're all correct! Unfortunately... I bought this hastily.. inexperience...

I've listed it again. The thing that bugs me is that the seller insisted it was a short shaft. She was an elderly lady. I guess there's a smaller market for long shafts because since I listed it two days ago not a single person has inquired. I suppose worse things can happen in life!

It may not be a total loss. There is a market for long shaft OB's . . . trolling motors and smaller sailboats tend to need the longer shaft motors. So, you could sell and then buy what you need.

"Standard" shaft lengths (transom height) are increments of 5" . . . 15", 20", 25", and even 30". 15" is commonly known as 'short shaft'.

 

[racerone]

I see listings all the time.------Short listed as long.------Long listed as short.-----Simply because sellers do not know their stuff !!

 

[Robbyracks]

I bought it for $900. It's an early 2000 model. That's a good price for that motor around here. I listed it for 1150 to cover gas, time, and factor in wiggle room with potential buyers... May have to drop price as now i have no motor (I want to use the boat this season) but I have another one lined up that is definitely short shaft.

My transom is 15" or 16"

 

[tpenfield]

I bought it for $900. It's an early 2000 model. That's a good price for that motor around here. I listed it for 1150 to cover gas, time, and factor in wiggle room with potential buyers... May have to drop price as now i have no motor (I want to use the boat this season) but I have another one lined up that is definitely short shaft.

My transom is 15" or 16"

15" . . . no such thing as 16"

The exact measurements are going to be a bit off from the 5" increments of transom height.

A short shaft motor might vary slightly above the 15", but as you saw your 20" shaft was around 22-23" with the tape measure.

 

[Robbyracks]

I see listings all the time.------Short listed as long.------Long listed as short.-----Simply because sellers do not know their stuff !!

Some of us buyers are pretty ignorant too!

 

[matt167]

Spend $100 on a jack plate