How to stop so much bow spray?

A general, non-powerplant specific, discussion on airboat technology, ie., hulls, rigging, polymer, etc..
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fireblue
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How to stop so much bow spray?

Post by fireblue »

Just bought an airboat and we are getting drenched haha

how can i cut down on the bow spray?

will a bow extension fix the problem and does anyone know where they are available? Are some designs better than others?

thanks in advance :)

Gary S
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Re: How to stop so much bow spray?

Post by Gary S »

Sounds like your boats not running proper.

diamondback0320
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Re: How to stop so much bow spray?

Post by diamondback0320 »

Usually raise back(prop side)of motor

terrible ted
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Re: How to stop so much bow spray?

Post by terrible ted »

To me I sounds like its running on the nose?

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Deano
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Re: How to stop so much bow spray?

Post by Deano »

Odds are . . . that this:
diamondback0320 wrote:Usually raise back(prop side)of motor
And this:
terrible ted wrote:To me I sounds like its running on the nose?
Are both correct.

No guarantee it will fix it (although it should help), but the place to start is with raising the rear of the engine. This is generally accomplished by placing fender washers between the rigging and rear motor mounts. As you add them, it should get better. If it starts to porpoise, you have to much of a good thing, take one or two back out.

If you [Search] these boards for things such as 'hook', 'plowing', porpoising', 'hull tuning' and the like, you will find massive amounts of information that will likely help your cause. Containing or deflecting the spray would be masking the symptom, you're much better off to identify and then address the root cause. :)
"The suppression of uncomfortable ideas may be common in religion and politics,
but it is not the path to knowledge; it has no place in the endeavor of science."
- Carl Sagan

fireblue
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Re: How to stop so much bow spray?

Post by fireblue »

Thanks for the reposnes guy, Deano especially. I did some searching and i now i do have a dent in the front of the hull which sounds like it would be called a 'hook' in airboat land :)
I'll sort out the dent, and see what happens, and then move on to adjusting the engine angle.

CHeers!

terrible ted
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Re: How to stop so much bow spray?

Post by terrible ted »

I that doesn't work look at how the boat is balanced as in were is all the weight. I have shifted batteries fuel tanks even 6 inches can make a difference.

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akblackdawg
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Re: How to stop so much bow spray?

Post by akblackdawg »

if you dent is in the front of the hull, less likely to be a problem. usually the plowing more likely caused by a dent just ahead of the transom, doesn't have to be a big one, 1/4 or 1/2 inch dent across the bottom a foot ahead of the transom is significant.
:alaska: If you ain't living on the edge, you're taking up to much space.

15x8 Alumatech hull, with enclosed cab, aluminum cage, LS 3, 6.2 aluminum block ffi, 2.7 Balistic Box, sensinich superwide 3 blade. Built for year around riding in Alaska

fireblue
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Re: How to stop so much bow spray?

Post by fireblue »

Thanks so much for the info guys, ill give the hull a good inspection and see what I can see.
Its good to know that bow spray is not something I have to put up with haha

fireblue
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Re: How to stop so much bow spray?

Post by fireblue »

Blackdawg your rig looks amazing!

fireblue
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Re: How to stop so much bow spray?

Post by fireblue »

I replaced all the engine mount bolts with stainless bolts and raised the back of the engine with 4 washers. Still heaps of bow spray...

I guess i need to go more washers??

The hull has a bunch of depressions not sure if this can completely prevent the hull from planing properly?

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John Fenner
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Re: How to stop so much bow spray?

Post by John Fenner »

fireblue wrote:I replaced all the engine mount bolts with stainless bolts and raised the back of the engine with 4 washers. Still heaps of bow spray...

I guess i need to go more washers??

The hull has a bunch of depressions not sure if this can completely prevent the hull from planing properly?
There lies the answer! My suggestion would be pull out rigging and set hull on flat concrete surface and knock out dents, be careful not to stretch metal by striking hammer onto aluminum that is in contact with slab. Also use a straightedge on stringers to find high spots and correct these issues as well. You typically want the bottom to follow a flat plane from transom edge forward with a small bit of crown about 4' forward.
I never finish anyth,,,.

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akblackdawg
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Re: How to stop so much bow spray?

Post by akblackdawg »

do a search for "hull jacks", they are set across the bottom under the engine area and put force down on the hull to help keep the dents from coming back, and can be used to push them out also. lots of photos of jacks on SA posts from the past, i think you will need 2 or 3 minimum.
:alaska: If you ain't living on the edge, you're taking up to much space.

15x8 Alumatech hull, with enclosed cab, aluminum cage, LS 3, 6.2 aluminum block ffi, 2.7 Balistic Box, sensinich superwide 3 blade. Built for year around riding in Alaska

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DDSBC
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Re: How to stop so much bow spray?

Post by DDSBC »

Run dry.
Micah Smith

BCAHCC, KRVSA and lifetime NRA member
12x7 Diamondback w/ rivited on poly, double rear driver double front passenger, full cage, 285 hp IO-520 swingin a 74" Whirl Wind Whisper Tip.

fireblue
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Re: How to stop so much bow spray?

Post by fireblue »

Ive not put in 7 washers on each side which has helped alot. Ill see about flattening out the hull now :) thanks for the "jack" advice!

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