Fishing Victoria Forum

I think I am having cavitation issue with my prop. It's 2 months old. 13 1/2 x 16. On 90 Hp. Anyone with any advice? I read that reducing the pitch might work. I'm thinking of getting another prop and using this as spare. Otherwise prop and motor are fine.

Sounds like you need a cavitation plate

What motor is it on

Inspect the hull in front of the motor and check the motor height.

I would not throw another prop on it as it will likely end up damaged as well. I think you will need professional advice to solve this problem.

fishnut wrote:What motor is it on

90 hp

sturgeon wrote:

fishnut wrote:What motor is it on

90 hp

Be a silly question im sure but you trimming it up ptoperly

I still cavitate when i get it wrong.

Bm

Hi,
I think if you were having cavitation issues you would know about it from the way the motor RPM flares up when it cavitates, it often happens when turning, just trim it down a bit and no problems.
Cheers,
Ango

Thanks.

Just a link to share.

http://uk.boats.com/how-to/propeller-ca ... ntilation/

sturgeon wrote:I think I am having cavitation issue with my prop. It's 2 months old. 13 1/2 x 16. On 90 Hp. Anyone with any advice? I read that reducing the pitch might work. I'm thinking of getting another prop and using this as spare. Otherwise prop and motor are fine.

When you say it’s 2 months old is that the propellor it’s not just the paint coming off due to erosion, is the aluminium pitted.
When I replaced my propellor to a stainless one it took 2 goes to get the pitch I was happy with to get the balance between speed and holeshot.
Is the wide open throttle rpm close to the engine manufacturers limits.when you are at max speed have you looked where your cavitation plate is compared to the water line it should be just on the surface if your engine is the correct height.

Like frozen pod said you might have to seek professional help if all else fails.

Yes, aluminium is pitted where the paint has come off. Initially I thought that was due to electrolysis due to the exposed aluminium but after rading about it, I realized that it is actually cavitation.

The max RPM is supp to be 6000. I am getting 5300 rpm. I am OK with the RPM. The issue from what I read is that overtime, cavitation would destroy the prop through the pitting. I have not gone to the back to look at the plate when I am at max speed. Still not that brave. Haha. But its definitely not ventilating. I know the difference between cavitation and ventilation. Ventilation occurs during tight turns when the prop comes out of the water. It is a distinctive sound. But anyway, I do not want to focus on terminology here as there is a great deal of controversy on the definition of cavitation and ventilation.

Who can I go to around Werribee for professional help?