long shaft on a short shaft boat

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pinchedfinger
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long shaft on a short shaft boat

Post by pinchedfinger »

What are the disadvantages of putting a long shaft outboard on a boat designed for a short shaft.
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cprince
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Re: long shaft on a short shaft boat

Post by cprince »

pinchedfinger wrote:What are the disadvantages of putting a long shaft outboard on a boat designed for a short shaft.
If you don't build up the transom, or some sort of jack plate type thing to bring the transom up to 18inches (I think that is the long shaft length), your motor will create a LOT of drag. Depending on the boat weight and size, you may not even be able to get up on plane.

An acquaintance tried a long shaft 15hp at a charity derby on a 14ft tinny... nothing but nose plow.

There are conversion kits for many Johnson and Evinrude motors to go from long to short shaft.

Try to trade the motor, or build up your transom. The cavitation plate needs to be at the same level as the bottom of the boat.

Craig
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1lastcast
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Post by 1lastcast »

I have a short 20 hp merc on my duck boat. I should be running a long shaft :oops: Its great in the shallow waters but forget about planing out. the prop comes out of the water and spins every time.

Maybe we can trade motors???
"My biggest worry is that my wife (when I'm dead) will sell my fishing gear for what I said I paid for it."
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