Cavitation

[tcsigler]

Hello, I have been reading alot of the posts on this site and realize that I need to backtrack a little bit. I was wondering what it means when you "porpoise" and what it means when you "cavitate". Seeing as I have recently acquired a new boat, I have decided that the more I know the better off I will be.<br /><br />Thanks for yalls help!!!

 

[PaulKim]

Re: Cavitation

Propoise is the bow going up and down, and not slicing through the water. Cavitation is when you get air bubbles by your plate. I can't remember the difference between cavitation and ventilation, but both deal with air by your cavitation plate, I believe. I'm sure someone more experienced than I can explain in more detail. Would be intrested in knowing the answer as well. By the way welcome to Iboats, I'm new to boating and love this site.

 

[Realgun]

Re: Cavitation

Catatation-When your motor revs higher than normal due to air being around prop and not water.<br />It happens when the prop is to close to the surface and brings air down to the prop. Also it is when the prop goes through the water and the underside is going so fast it lowers the pressure and the water actually turns to vapor. The colapse of this is what damages props.

 

[umblecumbuz]

Re: Cavitation

Cavitation occurs when air bubbles around trailing edges of prop collapse and eat away prop edges. Looks like localised corrosion. Also makes a recognisable sound on bigger vessels.<br /><br />Search google - 'propellor cavitation'. Plenty of tech info and research on the subject.

 

[18rabbit]

Re: Cavitation

Well, Tcsigler, welcome to the world of boats. You are correct, the more you know the better off you will be. Some of the best stuff to “know” is the stuff they teach in a free boating class. It’s not boring, it’s fun, and you learn all the nifty stuff about boating that helps keep you breathing air. Take a look at the websites for the U.S. Power Squadron and the U.S. Coast Guard Auxiliary. Both organizations do boating classes for free (or next to it). If you have already taken a boating course, then never mind.<br />

 

[mercrewser]

Re: Cavitation

Cavitation is when a completey submerged propeller seperates air from water. Ventilation is when the propeller pulls air from the surface.