Porpoise

A general, non-powerplant specific, discussion on airboat technology, ie., hulls, rigging, polymer, etc..
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gig_em13
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Porpoise

Post by gig_em13 » Mon Jul 20, 2015 11:30 pm

I have a 14 foot gilleo with a 220gpu front seat driver triple rear with slick bottom and it porpoises terrible I can't even find a "sweat spot" at all to even cruise. I really don't know how to help it I know I've heard all airboats porpoise but mine is unbearable any help is appreciated!!!
14'x7.5' gilleo 220gpu 72" whispertip!

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glades cat
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Re: Porpoise

Post by glades cat » Tue Jul 21, 2015 5:08 am

Lenco trim tab…when all else fails.
If you want the best recommendations, advise of any measurements you've taken or corrective measures you've done so far. Such as: checking bottom for straightness and hooks, torn/damaged poly, leveling engine or prop hub face perpendicular to bottom, weight distribution, balance point- fore/aft (check with 2x4 or pipe), etc. Pics will surely help.
The group will have a better idea of recommendations that may help.
Last edited by glades cat on Tue Jul 21, 2015 11:00 am, edited 2 times in total.
"Leave a legacy...Preserve the irreplaceable"
12' x 7' sled built by Scorpion, Cont. O-470-K, 72" Whisper Tip
Rigged by Gladescat & sons in 2009

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HAMMERHEAD
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Re: Porpoise

Post by HAMMERHEAD » Tue Jul 21, 2015 7:38 am

Use the search area at the top right of the screen. There is a lot of good info on the subject. Start with the bottom of the boat before you do anything else. If you don't you could be wasting your time.

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airjohn81
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Re: Porpoise

Post by airjohn81 » Tue Jul 21, 2015 10:17 am

just went through this w the same setup !!! level the boat on the trailer(level on top of stringers the best you can)..then put a level across the jugs to see where your motor is at compared with the stringers..(start with stringers level and motor level) test ride if still hoppin drop the back of motor a flat washer at a time till it gets better but not plowing... may need a hull jack under the motor as well as it helps the bottom and center stringer !!! all else fails... LENCO
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HAMMERHEAD
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Re: Porpoise

Post by HAMMERHEAD » Tue Jul 21, 2015 12:54 pm

forget everything you just heard and make sure the bottom of the boat is straight. If it is not nothing else you do will fix the problem. you should not have to use a trim tab.

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scottyroll
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Re: Porpoise

Post by scottyroll » Tue Jul 21, 2015 12:58 pm

HAMMERHEAD wrote:forget everything you just heard and make sure the bottom of the boat is straight. If it is not nothing else you do will fix the problem. you should not have to use a trim tab.
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jopete
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Re: Porpoise

Post by jopete » Tue Jul 21, 2015 11:02 pm

well, if my aunt had a pecker she would be my uncle. lol

people who have boats that don't porpoise are always the first to tell u u don't need a trim tab. if your hull is junk it might take a trim tab to make it drivable.

a set of jacks will go a long way in helping straighten out the hull and brace it if it is flexing.

like others have said, u got to get under the boat and find the problem, then u have a starting point.

good luck!!

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