Prop question

[1980champ]

Hi all I'm new to this sight but an old sea dog at boating,My question is .I have a 1980 champion bass boat tri hull design with a 115 evinrude.the cav plate is now 1 in above the bottom of the boat and a 22p raker.
Rpm are 5800 at 45 mph gps, why would a prop to loose it's lift and it's a new prop and it has never hit any thing I have it back at the local prop shop for the 3rd time in 2 weeks.any clues thanks.

 

[steelespike]

Re: Prop question

I would guess something other than the prop is wrong.Has the prop shop actually found changes in the prop?If it is changing you should talk to the dealer/manufacturer.I would suspect something happening to the hull perhaps a weak spot causing a hook near the transom.Perhaps hull shape changes under stress,waves,transom movement?

 

[Dhadley]

Re: Prop question

That's (gulp, hard to say) 25% slip. Something is wrong or at least could be better. Was this exact same prop ever better or are you comparing this one to another 22 Raker?

 

[1980champ]

Re: Prop question

Just got the prop back from the prop shop and he added more cup and did some thing els to the prop it had some problems ,and this a tru 22p raker he said it would work quite well now. thanks all and what speed do you all think I should get out of the boat