View Full Version : Cavitation?????

07-17-2011, 08:30 PM
I have read several threads here about cavitation. I'm not sure if cavitation is what i am experiencing...When we are towing I get a lot of what sounds like prop spinning. It seems to only happen when turning to the right. Any ideas or suggestions would be appreciated.

Ian Brantford
07-17-2011, 09:23 PM
It's possible. Does it matter whether the water conditions are glass or choppy? Does it matter if the boat is weighted in the rear? In addition to cavitation, one cause for the sound of the prop thrashing during a turn can be air sliding under the hull from the side. It mainly happens if there is some chop and the rear isn't weighted.

07-17-2011, 11:15 PM
it does it in glass and chop...seems to be more pronounced when towing. does it with weight in the boat as well as empty.

07-18-2011, 03:21 PM
I just got my Moomba Outback and seriously love it. If I mistakenly leave on the blower, after the engine is cranked sometimes the blower noise changes pitch (sounds like the blower is reving up) and I think I could have mistaken it for cavitation if I were going faster. In my case, I had the dealer check the blower on the initial service and they heard it too but there was no detectable problem - still happens ... will continue to monitor and try to track down what is the cause but certainly it does not seem to be causing a problem.

07-18-2011, 04:52 PM
Years back I had cavitation when towing a three person tube and turning to the right. Sounded like the prop was catching air or slipping. I believe it was from the prop I was running at the time which was a stainless 13x18.5 (if I recall) speed prop. Different props seem to carry different sounds, growls, etc. with them under different conditions.

07-20-2011, 01:55 PM
I am planning to change the prop to see if that helps. As far as I know the prop on it is the stock 4blade, no idea if the size. I have heard the Acme 1837 is a great pick. All we do in out boat is tow large towables.

07-20-2011, 03:31 PM
This is what 30 years of cavitation on a rudder looks like.... In this case, you can't tell while driving the boat nor can you hear it.