# boat nose dives badly



## bayougrande

aight this is what i got 

16ft v bottom boat w/ 90hp evinrude 20"shaft motor.

i can run the boat fine up to 25-30- mph depending of which way i'm running into the wind. and i have plenty of throttle left. but when i give it just a hair more throttle the nose dives extremley bad no matter how far i trim the motor. I've heard from a couple people that some boats are built with a "hook" in the back of the hull. If this is true how can i get my boat to run like i need it to?

thanks


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## Speckulator

Please explain!!!! Front end bounces up and down? Boat's tryin to submarine? Need more info.

George


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## BIGRIGZ

never heard of a hook. 

Is the trim switch hooked up backwards or being used opposite of what it's supposed to?


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## Buckyt

Some boats can develop a "hook" if they don't fit the trailer properly. ie. if they hang over the back of the trailer supports and have a heavy motor left on the transom. A lot depends on the type of boat, aluminum, fiberglass, age, etc. You can check this by placing a straight board on the bottom of the boat spanning from the transom forward. If there is a hook, there will be a space between the board and the bottom of the boat.

This can cause the boat to nose dive depending on the severity of the hook.

Do you have a add on planing fin installed? If so, this can be a problem if not installed properly.


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## Tuna Man

A hook in a hull will/can cause the hull to act like a suction cup on the water. Hooks can also be caused by hitting something, thus putting a dent in the hull, be it fiberglass, or metal. Opposite of a hook is a rocker, and effects are opposite.


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## off route II

> *Tuna Man (6/9/2008)*A hook in a hull will/can cause the hull to act like a suction cup on the water. Hooks can also be caused by hitting something, thus putting a dent in the hull, be it fiberglass, or metal. Opposite of a hook is a rocker, and effects are opposite.


years ago my dad bought a boat (early fiberglass days) that had a hook in the bottom. we had to keep a big bag of sand in the bow to kep it from beat'in you to death.


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## DOUBLE "D" & LV

What is your boat made of? You need to inspect the hull and determine what is causing it. Depending on what your boat is made of, then there are different things to do to fix the problem. The other aspect of this may be the engine height.


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## X-Shark

For the most part a hook will act like a trim tab in the down position. Thus pushing the Bow down, even if you trim the motor out.


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## bayougrande

the boats fiberglass and it sits with six inches of trailer bunks past the transom(but i don't know if it did ever sit on a trailer for a long time) and that is what i was told could most likely be the problem . since the boat is an 86 but it's not soft anywhere and i ran a board down the bottom and no gap. I've also heard from an old wise man that used to drag race boats that said he used to sand the hook out of a boat to make it reach top speeds. does anyone know how to do this and another idea i have is if i lower the motor farther than it needs to be would that help. It sits in the right postions now. I also tried taking the dolf-fins off the motor to see if that was making the nose dive and itdidn't change it a bit.


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## wld1985

I'm with what was said a few post up.... It could possibly be your motor height.. How far past the boat does your motor sit???


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## X-Shark

> i ran a board down the bottom and no gap.






That tells me there is no hook in it, but you should use something like a 4ft level to check it.


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## DOUBLE "D" & LV

Do you have a bass boat? What kind of boat/ brand of boat do you have? This may help determine your problem.


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## Xanadu

Post a picture of the boat and order some bennett trim tabs.


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## bayougrande

aight i'll try and upload a pic but the boat is a saltwater boat 16ft. warrior craft center console. 

the motor sits on the transome there's no bracket


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## bayougrande

i might try and adjust the height of the motor ...... if so does anyone have a good used jack plate? man or hydr. perferablly manual because it's cheaper!


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## Flounderpounder

Where does your cavitation plate sit in relation to the bottom of the boat? Use a straight edge to determine this. It should be slightly BELOW the hull (maybe 1/2 to 1 1/2 inches). If not, and you have room on your bracket, definately try dropping it down a hole!

Also, as strange as it sounds, the wrong prop (for example, too much "cup") can do some weird things to a boat's handling sometimes. You might want to call the guys at Accu-prop, and describe your problem. Let us know how you are making out!

OOPS...just saw where you said you have no bracket. Sorry. It would still be interesting to know where the cav. plate sits. A jack plate might be the answer, but kind of hard to tell w/limited info!

:takephoto


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## Sequoiha

It could also be a condition called a Power Hook, If you have a soft bottom or a broken or rotton stringers, the more power you put to the boat the more prevelant the hook is.. causing the diving condition,, get off the gas and the power hook goes away,, this also cant be seen with a straight edge.. but you can lay under the boat and push on the hull to see if it is soft... this condition is most noticeable at heavy throttle and upper ends of the speed spectrum..:usaflag


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