PORPOSING

[SantaG]

This Palmbeach Hull Porposes SO
Bad that when the TrimTab is down enough I'm Lucky if I get 30MPH & will get stuck in the grass.I've tried moving the fuel Tanks Forward
Backward,changing the Pitch of the Motor,moved the Batteries from the Cage to the Floor-rear then front.,
4 Cyl.Lycoming-Pollymer Botton-single Rutter.HELP !!! I don't know what else to TRY.Ran the Fuel tank{s} Full/empty.Any Ideas or is it ANCHOR time ?? TIA SantaG

 

[Duckhunter_012003]

[/i][/b]
I had the same problem with a boat that we buil, it was a full decked round chime hull like a Kline out of all 1/8" alum with a 180hp on it, and it was bad with porposing,But i had a sloid alum grassrake on it which was 4ft long, and just a quick and minro sloution was we put about 4-6 sandbags up on the edge of the bow where the grass-rake meets and your add about 150-180lbs on the boat, so it stop porposing, and it wasn't permanent but it got me out there to where I could finish up the deer season with out having to take the boat apart to fix it. If you try this though, be careful if you run over any steep hills and go down the other side into water, cause i did this about the 5th time out and my boat duck-dived right under and sank in about 3ft of water. Just give it a try if you got a rake on your boat. Plus there are other sloutions out there, but this is quick and easy.

 

[Daddy Dave]

You also might want to try either leveling the floor jack to keep the runners from flexing or take a close look at the runner welds or rivets near the transom to see if they have worked loose. In almost every case, porpoising is caused either by a hull rocker (bulge) at the back or weight shifted too far back on the boat.

 

[c chardt]

Dose the bottom of the hull stick out past the transom like a 1'' lip if it dose you can take a 3 lb hammer and knock it down a little not to much or it will push on the nose works very well saw it first hand on 2 boats this weekend they both porposed crossing the lake got to the dam and stoped on the dam smacked them with the hammer and they did not porpose the rest of the day no matter how fast they went

 

[Croc1]

I had the same problem and about 2 weeks ago I did what cchart said to do now it runs out WOT with no porposing I also put 5/8" in front jack and put rear jack at O" put the rear lip just a hair past flat each time you unload the boat it pushes it back up a hair so in a few months when it starts porposing you just tap it down a bit again .using the trim tab the boat handled bad and used large amounts of gas now I dont use my trim tab at all

 

[c chardt]

The thing is with a trim tab you only put it down enough to stop porposing and when you turn corners you have to pick it up or it pushs on the nose and handles bad as for burning fuel mine burns the same up or down I'm always adjusting mine up and down for the depth of the water and I always pick it up in the corners no matter what.

 

[marshmaster pat]

CC- you sound like me with the trim tab. I found that there is never one setting to make that boat trim out right. Going with the wind, against the wind, crank up the RPMs, or going around a wide corner all require the trim to be adjusted to make that baby sail right.

And boy it makes the difference.