Prop cavitation

Mattblack
Rank: Gummy Shark
Rank: Gummy Shark
Joined: Tue Sep 06, 2016 1:08 pm
Location: South East Suburbs
Has liked: 625 times
Likes received: 298 times

Re: Prop cavitation

Post by Mattblack » Sat May 05, 2018 1:51 pm

is this the same boat that you bought new that had ride, planing & porpoising issues?

Nude up
Rank: Kingfish
Rank: Kingfish
Joined: Thu Aug 08, 2013 5:08 pm
Location: Bellarine peninsula
Has liked: 333 times
Likes received: 569 times

Re: Prop cavitation

Post by Nude up » Sat May 05, 2018 1:57 pm

sturgeon wrote: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?
Reducing the pitch will increase the rpm I would have thought your rpm should be closer to the recommended. I have read that reducing the pitch will reduce cavitation. I can’t help you with a good mechanic I do most of mine myself if I have needed specialist help I have gone to port Phillip boating centre in hoppers having only had yamaha’s They have done a few jobs for me and have been ok they also have given me good advice

canned_tuna
Rank: Premium Member
Rank: Premium Member
Joined: Sun May 11, 2014 1:27 am
Has liked: 15 times
Likes received: 79 times

Re: Prop cavitation

Post by canned_tuna » Sat May 05, 2018 4:28 pm

sturgeon wrote: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?

Not Corey Gauci.............

frozenpod
Rank: Premium Member
Rank: Premium Member
Joined: Thu Sep 27, 2012 2:04 pm
Has liked: 81 times
Likes received: 109 times

Re: Prop cavitation

Post by frozenpod » Sat May 05, 2018 10:10 pm

sturgeon wrote: 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.
Who can I go to around Werribee for professional help?
If you are only reaching 5300rpm you are either massively over propped or something else is a miss. You will need to resolve this as this will overload and can damage your engine.

No idea about who to talk to in Werribee but I would talk to Solas.

My gut feel is there is something on the hull in front of the prop causing a disturbance bubbles ect that is causing cavitation.

smile0784
Rank: Premium Member
Rank: Premium Member
Joined: Thu Apr 26, 2012 5:16 pm
Has liked: 39 times
Likes received: 356 times

Re: Prop cavitation

Post by smile0784 » Sun May 06, 2018 1:56 am

Is the motor at correct height

User avatar
bowl
Rank: Premium Member
Rank: Premium Member
Joined: Mon Nov 19, 2012 12:30 pm
Location: Wyndham Vale
Has liked: 292 times
Likes received: 559 times

Re: Prop cavitation

Post by bowl » Sun May 06, 2018 1:14 pm

Port Phillip boating centre , south side marine, moolap marine

Nude up
Rank: Kingfish
Rank: Kingfish
Joined: Thu Aug 08, 2013 5:08 pm
Location: Bellarine peninsula
Has liked: 333 times
Likes received: 569 times

Re: Prop cavitation

Post by Nude up » Sun May 06, 2018 6:47 pm

Solas is who I bought my prop from. The first prop I got to 6000 revs with only half throttle on the plane in a flash the second prop dropped the rpm to 5700 at wot really happy with it. It only cost me postage to swap it over.

sturgeon
Rank: Cephalopod
Rank: Cephalopod
Joined: Sat Nov 25, 2017 3:57 pm
Has liked: 14 times

Re: Prop cavitation

Post by sturgeon » Sun May 06, 2018 10:39 pm

Thanks. Ok. I will Google Solas.

Post Reply

Return to “Boating”