# Gheenoe Transom Height



## dkives (May 22, 2010)

I have a 15’4” high side Gheenoe with a 15 hp Yamaha 2 stroke motor. 
The motor was too low, so I raised the motor 3” to make the cavitations plate 1” above the bottom of the boat. Before the move, I could get 22 mph with 2 people in the boat. Now I get 24 mph, but I’m getting water in the back of the boat when I let off the gas. 

Has anyone else experienced this problem? If so, is there some way to minimize the backwash into the boat? 

Thanks,
Burgman


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## noeettica (Sep 23, 2007)

Welcome sir ! [smiley=1-beer-german.gif]

A little more weight in the bow ... back off slower ...

Dave


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## rashouri87 (Jul 2, 2009)

I dunno about brand new gheenoes, but my 15'4 is rated for a 10hp!  If this is the case with yours, then you may have too much squat in the rear hence the water.  I would just learn to back the throttle off slower or try to move battery and gas to the front and you should be good. Also consider getting a good bilge pump! ;D


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## dkives (May 22, 2010)

Mine is rated for a 10 hp. But the 10 weighs as much as the 15. Before I raised the motor up 3 inches I did not have the problem of water coming over the back. 

I think it has something to do with how the water hits the cavitation plate. It doesn’t seem to make any difference if I let off the gas fast or slow. With a trolling motor, battery and my wife up front it almost wants to take on water when I take off.

Today I made a plate to bolt to the transom to deflect the water back down. Maybe that will take care of it, I hope.

Thanks for the help


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## noeettica (Sep 23, 2007)

What do you guys weigh ? I run mine with 2 172 pound adults ...

I run a 13 and don't have a problem , I run the battery up front 

but I will check this next time ...

Dave


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## ducktrooper (May 6, 2008)

I have similar issue...added a Bobs' Mini Jacker and raised 15 HP about 3". I'm now getting lots of vibration through the hull at full throttle. Could it be I have it too high?


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## dkives (May 22, 2010)

I built a jack plate first, but didn’t like the motor sitting 3 to 4 inches further back. That might have something to do with the vibration but I didn’t notice it with the jack plate on. I think 3 inches is just right for height.

I made a riser out of two ¼ alum. plate and hard plastic. Mine is 3 inches strait up and I do not cavatate and the water pump is getting water.

I made a shield on the back and it seems to take care of the water coming over the back. I’m happy with the way it works now.

If I had more balls I would look over the back when going wide open to see what it doing back there but that Gheenoe is to narrow in the back.


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## Un-shore (Sep 27, 2007)

I think its because you are going faster and the prop is closer to the surface so what ever water it is "plowing" forward when you let off has less restriction to surface and comes over the stern. 

Plus, the same rule that makes it plane better three inches higher has the opposite affect as drag when you stop. When the prop was lower it would drag better and pull the bow down. The drag on the motor when its higher pulls the stern down.

At least thats my unedgycated guess.


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## el_scorcho (Oct 23, 2008)

Have 15 HS with a 15hp, with about 3 inch home made jack plate. Not really a plate though. Used aluminum C Beam, looks like an I beam split down the middle. Its strong, light and there is no flex or extra vibration. Little bit of set back, but have not noticed any change in the performance of the boat. 

No issues with water comming in when comming off of the throttle. I keep the boat very light though.


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