cavation

[jeanlakejim]

Hello anyone.

I just bought a new 14 ft alummiun crestliner sportsman boat with side consoule equipt with a 25 yahama 4 stroke with power trim and a prop size of 9-7/8'' x 9 ''. I'am into fishing alot and i'am fishing lakes and rivers. I know that cavatation plate should be riding on top of water while on plane, But mine ride an inch below water line. Would this cause cavation ? Also i have an homemade prop guard made up to protect both foot and prop. When i have WOT going stright the motor runs fine with no cavatation. As soon as i steer her port or starbord the engine cavatates badly. My anti-cavation plate is sitting 1'' - 1''- 1/2 below my keel. Is there anything i can do to stop cavatation.

Thank you.
JeanLake Jim.

 

[JB]

Re: cavation

Your anti-ventilation plate is definitely too low. It should be even to about 1" above the keel.

If you are ventilating the prop it could well be because the av plate is too low but it could also be a trim problem.

Start by raising the AV plate to keel level and experimenting with trim.

Let us know what you get.

 

[jeanlakejim]

Re: cavation

I raised my motor up so the a-v plate is about 1/2" above my keel and it still cavates on turns. I also noticed that when driving in to the wind the motor will cavatate going stright. Also i noticed that my a-v plate is still riding under the water. Would a hydrofoil help me in this situation? , or could it be prop size?

 

[rodbolt]

Re: cavation

try it without the prop guard.
could be cavitation or ventalation.