I have a 1987 24' Pontoon, with a 1983 115hp evinrude with a couple problems.
I bought this pontoon last year and completely rebuilt it. All new floor, seating, console, steering cable, etc. Re-welded all the railings, made it like new again. I got the 115hp evirude for it and am using it.
The problem, I believe is ventilation. Once I get going up around 17-20 mph the prop acts like it is slipping. RPMs go up about 500 and we slow down a little. The prop was new last year (15p) and I tried marking the hub to check for slippage, and the marks stayed aligned. At 17mph the motor is sitting around 3000rpm. With more weight on board we can get up to 20mph, but with just 2 people the problem starts at 17mph. The motor is mounted as low as it can go and I tried raising it, but that only made the problem worse. If I remember right it has 23? pontoons. I tried to make a bracket to lower the motor further, but the steering cable got in the way, it is almost sitting on the mount now. I just ordered a hydrofoil and 4 blade 13p prop to try. They will be here Wednesday, and I will take it out to test Thursday. If anyone has any ideas to help let me know.
I've had a very busy spring and only got to get it out on the water for the first time last Saturday, which just reminded me of these problems, while I had been working on the trailer problems I had. I have family coming Wednesday to visit and we are hoping to take a ride down the North shore to Duluth to watch the fireworks on the 4[SUP]th[/SUP] from the pontoon.
I bought this pontoon last year and completely rebuilt it. All new floor, seating, console, steering cable, etc. Re-welded all the railings, made it like new again. I got the 115hp evirude for it and am using it.
The problem, I believe is ventilation. Once I get going up around 17-20 mph the prop acts like it is slipping. RPMs go up about 500 and we slow down a little. The prop was new last year (15p) and I tried marking the hub to check for slippage, and the marks stayed aligned. At 17mph the motor is sitting around 3000rpm. With more weight on board we can get up to 20mph, but with just 2 people the problem starts at 17mph. The motor is mounted as low as it can go and I tried raising it, but that only made the problem worse. If I remember right it has 23? pontoons. I tried to make a bracket to lower the motor further, but the steering cable got in the way, it is almost sitting on the mount now. I just ordered a hydrofoil and 4 blade 13p prop to try. They will be here Wednesday, and I will take it out to test Thursday. If anyone has any ideas to help let me know.
I've had a very busy spring and only got to get it out on the water for the first time last Saturday, which just reminded me of these problems, while I had been working on the trailer problems I had. I have family coming Wednesday to visit and we are hoping to take a ride down the North shore to Duluth to watch the fireworks on the 4[SUP]th[/SUP] from the pontoon.