Cavitation problem on Zodiac Fastroller 325

[highcyclic]

Hi Gang,

Just upgraded my old 1997 Zodiac 310S to a Fastroller 325 with Active V air floor. All chambers pumped up to pressure, air deck pumped up to the 11 PSI. Yamaha 2 stroke 8 hp short shaft (brand new). Open throttle gets up onto plane and immediately cavitates, I can feel a giant air pocket under the boat near the rear, shifted weight around to where my dad sat across from me in the rear on the floor and it goes away. I am pretty disappointed right now after spending money on a new boat and then 250 dolars on a electric air pump to ensure air hull is inflated in a decent time frame. So basically if I don't run that configuration, of a person sitting in rear on floor it seems to have this air pocket there. I also played around with all trim level and the second slot up gives me best results, but the 3rd up gives me the best trim and if he sits on the floor it works.

Suggestions, ideas? On a plus the boat rides mch nicer in rough water than my 310 did with wooden floors, a tad slower with the air floor though, getting about 25 km/h on plane now, hit close to 30 on the old boat.

 

[Sea Rider]

Re: Cavitation problem on Zodiac Fastroller 325

Seems active V floor is floating sib more than it has to, could you try a long shaft out ? What's your transom to keel distance in cm ? Does you transom have a middle cut or it's a sltaright transom model ? Engine should be trimmed to have a perpendicular engine once sib is floating and just distribute weight inside deck towards bow.

Happy Boating

 

[fbpooler]

Re: Cavitation problem on Zodiac Fastroller 325

The floor should not have an effect, so check to see what the recommended transom height is. Put several sealed 5 gal buckets in a boat, and it will not float as high in the water due to the weight of the buckets. The same principal applies to an air floor unless you change the shape of the floor.

Make sure the air floor is inflated correctly.

 

[Sea Rider]

Re: Cavitation problem on Zodiac Fastroller 325

If deflating that V floor, won't have the necessary rigidity to cut water flow well, that's why needs to be 11-12 psi top inflated or keel will rock as a marshmellow. On that kind of sibs the V floors forms the keel, does't have an air mat on top as there is no lower fabric as found in traditional alum or air floor sibs.

Happy Boating

 

[highcyclic]

Re: Cavitation problem on Zodiac Fastroller 325

Spent all day on the internet, many others experiencing this with air floors, the answer is weight distribution and ensuring air floor is properly inflated along with tubes from what I have read. Like I said after an hour his problem went away so must also be the tubes settling in on the airfloor and making it more rigid. Just realizd I posted twice....duh

The floor should not have an effect, so check to see what the recommended transom height is. Put several sealed 5 gal buckets in a boat, and it will not float as high in the water due to the weight of the buckets. The same principal applies to an air floor unless you change the shape of the floor.

Make sure the air floor is inflated correctly.

 

[fbpooler]

Re: Cavitation problem on Zodiac Fastroller 325

Interesting. Our 285 Fastroller has a normal fabric floor attached to the tubes. The inflatable floor has an attached keel piped to the floor so both are inflated through the same fitting. The inflated bottom profile is the same as a boat with a wood or aluminum floor.