stability problem with boat

Joined
May 28, 2003
Messages
23
Ok here is my story, I restored an old '73 checkmate mx-15 this year and now she is all done and I took her out last weekend. It has a good size motor on it ('75 johson 135) and plenty of power, so much that it cavitates a bit when you really get on it. I'm mostly happy with it except for one thing, after you get up on plane it bounces up and down quite bad, I Tried all different trim settings and weight distribution and it did better with only 2 people in the front seats but still pretty bad, its not so bad on really calm water but an sort of wake and she is teeter-tottering back and forth (front to back). I'm looking for suggestions on how to fix this, A friend suggested a hydra-foil on the lower unit and another suggested trim tabs and another suggested moving weight to front of the boat, I am open to any or all suggestions, thanks.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: stability problem with boat

A fin on the motor will help. Trim tabs will help but most likely slow you down. Moving weight forward will slow you down.<br /><br />A better technology prop will help. What prop are you running now? Jackplate?<br /><br />Good luck!
 
Joined
May 28, 2003
Messages
23
Re: stability problem with boat

no jackplate yet, the propshaft sits about 6" below the bottom of the boat. I think i may try a hyrofoil, they seem cheap and easy to do, does anyone recomend a certain brand or style? I really don't want to have to drill any more holes in my transom for trim tabs and moving weight to the front seems very difficult too. My prop is an aluminum 13" x 19 pitch michigan wheel cup prop.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: stability problem with boat

See if you can try another prop. Something like a Stiletto or Turbo. They will offer you a lot more stability. If you are even thinking about a jackplate, get it first. That will change the whole prop deal. <br /><br />And truthfully, without a jackplate you may not like the fin. Remember - the fin will do strange things if its underwater.<br /><br />A trim unit will really help you fine tune it.<br /><br />Good luck!
 
Joined
May 28, 2003
Messages
23
Re: stability problem with boat

well i don't think i have the cash for the prop and jackplate right now (just dished out 1100 for a new paint job) but maybe a winter project. I think i will try the fin since its cheap and i can easily take it off if i don't like it. its not that the "pourposing" (spelling) is bothering me that bad, i realize i have a small boat, heavy motor and rough water is always going to be a rough ride, im just trying to make it a bit safer. Thanks for the suggestions
 
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