prop hub going? or cavitation?

[jake069]

Hi, I've got a 23' avalon pontoon w a merc 115 4 stroke. both 2014. with a few people on the boat, all is fine. When the boat is near max capacity, anything over 1/2 thottle acts like the prop is coming out of the water. Could this be a spun hub? Doesnt matter if we put the heavy guys in the back.

Thanks,
Jake

 

[jimmbo]

Have you tried another prop? What is your current prop, brand and model?
Condition of current prop, bent or broken blades?
I believe Mercury makes props specifically for Pontoon Boats.

 

[GA_Boater]

When it's loaded with peeps, where are they sitting - In front, lifting the rear?

What happens when the trim is adjusted - Any change?

 

[oldman570]

Marking the prop nut and prop will tell what is happening. Place a paint mark on the nut and prop inline, and the next time it happens you will be able to tell if the prop has spun or it is cavitation.

 

[jake069]

When it's loaded with peeps, where are they sitting - In front, lifting the rear?

What happens when the trim is adjusted - Any change?

Prop is in good shape, No change when adjusting trim. People are evenly distributed. we'll move more weight to front or back, with no change

 

[oldman570]

With the added weight of the more people, it is more the likely that the prop is to high a pitch for added load. You could go to the dealer where you bought the toon and see if they would let you try a lower pitched prop to see if that is the trouble. The IBoats or Solas prop web site has a prop calculator, and other info, about what makes a good prop for certain