Cavatation with a whale tale?

[mphy98]

just took the new old boat out for the first time today, ran great but out of the hole it started out good then the engine race like it had no propeller on it, rpms raced up, i pulled back on the throttle and eased it back up slowly and i got to speed and plane no problem, i think i did not have the lower unit all the way down as well. when i did put the unit down all the way this seemed to get rid of the problem. this is my first io so can a whale tale make cavitation happen or do you think it is because i did not have the unit all the way down. probably 85% down. 79 thundercraft 140 merc io. thanks in advance.

also had the top on as it was only 55 up here, quite noisy. should i replace that old yellow foam in the engine cover with a more modern sound deadener? and would that help that much with the noise? talking about that foil covered stuff or sound mat from best buy. thanks again bob

 

[Mike2076]

Re: Cavatation with a whale tale?

Hello,make sure your whale tail is level or no more than a inch lower than the bottom of the boat if it higher you need to lower your motor,if all thats right you might have a spun hub in your prop,try it with motor all the way down and trim out once your on plane.Good luck Mike

 

[Ram58]

Re: Cavatation with a whale tale?

As Mike said, start out with the lower unit all the way down then once on plane trim out for optimum ride. I had a Stingray on my last boat and it didn't cause cavitation. It was mounted to AV plate even with the bottom of the boat.

 

[tashasdaddy]

Re: Cavatation with a whale tale?

be smart, loose the whale tale and spend $100 on the right item to do the job correctly.

the blems are on sale only at iboats.com. http://www.iboats.com/Nauticus_SX_S...3703934--**********.040014060--view_id.352485

 

[ziggy]

Re: Cavatation with a whale tale?

loose the whale

that sounds like a good idea... at least try it out w/o the whale tail. i've had one, once. got rid of it after it broke my vent. plate. never to go back to one either... tabs of some sorts if i need a lift.

to do the job correctly.

which would be, lifting the boat at the back (via trim tabs), not lifting the drive (via a whale tale) to lift the back of the boat.. some folks like these tales. but they sure seem to cause a few problems to go along with what they're trying to accomplish.. as others have said. definitely trim all the way in/down when starting out from dead in the water to going to above plane..

as for the noise. the top up will make it sound louder. it's trapping the sound. so maybe try it w/o the top up and see if it's too loud then. if it's still to loud. then ya could approach the replacement of the sound deadener.