Pontoon boat Engine too low?

[PontoonJunk]

Hello, Ive got problems. Just got this old 90 24' pontoon with a 115 evinrude on the back. Took her out on the water and at level trim the prop doesnt get any traction the second you touch the throttle and it just "slips out" The only way to go faster than 5mph is to trim all the way down to the point where the engine is -4" level, then the bow of the boat is just inches from the water waiting to get swamped from waves. Gets up to 24mph like this. My question is my motor way to low? After doing some digging it seems I need to have the cavitation plate an inch or so bellow the water level and from looking at my photos its like 10" below sitting water level.
Its not letting me upload a photo. My engine cavitation plate is sitting level with the bottom of the toons

 

[racerone]

Have you tried another prop ?----The hub could be slipping.

 

[ahicks]

Have you tried another prop ?----The hub could be slipping.

?? He can get 24mph out of it.

 

[ahicks]

Hello, Ive got problems. Just got this old 90 24' pontoon with a 115 evinrude on the back. Took her out on the water and at level trim the prop doesnt get any traction the second you touch the throttle and it just "slips out" The only way to go faster than 5mph is to trim all the way down to the point where the engine is -4" level, then the bow of the boat is just inches from the water waiting to get swamped from waves. Gets up to 24mph like this. My question is my motor way to low? After doing some digging it seems I need to have the cavitation plate an inch or so bellow the water level and from looking at my photos its like 10" below sitting water level.
Its not letting me upload a photo. My engine cavitation plate is sitting level with the bottom of the toons

Struggling with the semantics here. Are you saying it'll do 24 mph with the motor tucked in all the way? So it's sort of lifting the back of the boat up under power?

What are you using for reference when you say "level"? Would the prop shaft be parallel with the pontoons, or something else?

Maybe back of boat squatting, and prop shaft parallel with the water's surface?

 

[PontoonJunk]

Struggling with the semantics here. Are you saying it'll do 24 mph with the motor tucked in all the way? So it's sort of lifting the back of the boat up under power?

What are you using for reference when you say "level"? Would the prop shaft be parallel with the pontoons, or something else?

Maybe back of boat squatting, and prop shaft parallel with the water's surface?

Yes it will do 24mph with the engine all the way down tucked againts the transom at a negitive angle, there for pushing the back of the boat up and the front for the boat down. im saying Level trim is the motor parrallel with the toons and it wont even attempt to move faster than 5mph without loosing traction

 

[PontoonJunk]

?? He can get 24mph out of it.

I have not tried another prop but I kinda thought thats ruled out since it has no problem performing at negitive trim

 

[PontoonJunk]

View attachment 20220419_184910.jpgThis is what it looks like at "level" trim where it wont move out of its own way

 

[Scott Danforth]

Pontoons need a hydraulic jack plate in addition to T-n-T.

 

[ahicks]

Judging by it's appearance in that pic, and what you are saying, the motor is certainly not too low. It's more likely not deep enough.

If it's not already, a cupped prop MIGHT help.

 

[bsktball55]

By your description, it sounds like you are trying to take off with the motor already trimmed up. Start with it fully tucked and then trim up as you get moving.