Honda 90 on pontoon prop issue?

I took our pontoon out for the first time this year and on first run after about a
45 minutes of cruising the motor sped up in rpms like a prop slip, so cruised back in at slow speed! The next day we went out cruising made several stops and after about and hour and a half it done the same thing, both instances I had 8 people on board! The next day I took it out with just two people for about two hours accelerating and stopping in random sequences and it never did it? The prop and hub is a Michigan vortex and was new last year and there are no vibrations or noise in the lower unit and I put new fluid in it this year, the old was very clean! Any ideas or suggestions of what could be going on, I am kinda baffled about it wondering if it just got trash or cold water pockets cauSing cavitation or what? Thanks in advance for any helper ideas!!!

Dirty hull causing cavitation? Engine height if too many people go too far forward? Did it change when you trimmed the engine down etc? Note that if your prop starts to cavitate it might need to be taken completely out for gear for a short period before it will grab again.

Toons were cleaned before I put it in the water . The trim was in level and I plane it down more with no difference. Somebody said if it cavitates or does it again to throw into reverse and it will clear out? Any truth there or more ideas, I just don't want to encounter any on water troubles! Thanks

I would have said the same as Aliboy....especially "too many people up front". Most people on pontoons tend to sit up front. That will cause the back end to raise up too high.

One other thing that could cause your problem. Being loaded down puts more strain on the prop. The Vortex has a removable hub. Two things that could be going on there....

1. The prop may not be properly torqued and when under strain, the hub is spinning.

2. The hub could be cracked or damaged and the hub could actually be spun...but maybe not enough to be causing the problem all the time.

You can remove the prop and remove the hub to inspect.

Just a couple of thoughts.

Mike

I have had many issues like this with my bf90 on my 26ft toon. Got to be cavitating. Mine will do it it it gets to choppy in the bay. Thought I had a major prop problem but mostly just conditions!