Extra Long Shaft engine on 20" transom

[jwd000]

Hi guys,

I am looking at putting a new Yamaha 115hp onto my boat. The boat has a 20inch transom. I'm told the correct engine length for this is the "long shaft".

I have an option to buy an "extra long shaft" version for $1000 less and wanted to know if this will work on my transom.

Having a motor too short has obvious issues but I wanted to know what problems a longer than normal engine might/will cause.

Anyone?

Thanks in advance.

 

[tmcalavy]

Re: Extra Long Shaft engine on 20" transom

A little more drag and a little less hole shot and top speed.

 

[Frank Acampora]

Re: Extra Long Shaft engine on 20" transom

Plus also spraying water off the leg up into the splashwell at speed. Most outboards have a small horizontal fin on the front of the leg about the height of the water pump --about a few inches above the anti-ventilation/cavitation plate. The purpose of this fin is to deflect water that impacts and rides up the leg. 5 inches too long of a leg will put this under water and make it ineffective. Water will ride up the leg and into the splashwell.

On the other hand, 1,000 buys three manual jackplates or one hydraulic jackplate. So buy the engine and buy a manual jackplate to get it high enough. You will still save money.

 

[tashasdaddy]

Re: Extra Long Shaft engine on 20" transom

if it is a 25 inch shaft, you will need a jack plate.

 

[jwd000]

Re: Extra Long Shaft engine on 20" transom

Thanks guys.

 

[jay_merrill]

Re: Extra Long Shaft engine on 20" transom

Not that I disagree with anything that has been said here, but just out of curiosity, what kind of boat are you thinking of putting the motor on?