Motor location questions

[Fred J.]

I recently bought a 2002, 22' fish & cruise by Voyager with a 2005, F115 Yamaha. I am new to the pontoon experience. First I had the wrong prop so changed to a 13 pitch which put me at the right RPMs. You cannot hardly trim up this motor w/o causing "ventilation"? The design of the transom appears to me to cause the water to part away from the prop. The transom is approx. 4' long from front to rear with a downward angle to rear. If you project the plane of this angle back to the prop, you will hit about mid-prop. That is with the motor trimmed to level in the water in relation to the bottom of the pontoon.

Am I assuming too much to think that the water is parting away from the prop based on this scenario? The motor appears to me to have only one more hole to drop to gain
3/4" or so. Would a "hydofoil" help. What are some possible solutions to avoid ventilation and allow more trim up?

 

[5150abf]

Re: Motor location questions

If you can drop the engine aother hole I would try that, you can't do much about the engine pod, it is what it is and trim on a pontoon doesn't really do much at all.

I think a foil would make things worse as it would lift the engine even higher out of the water so I would skip that, drop it the last hole and see what you have then.

 

[Fred J.]

Re: Motor location questions

Thanks Cap. for the input. I see the logic of no foil, especially since the pontoon already has the sensation of plowing in the front end. I wonder if a person could retrofit another type transom. I was at Bass Pro the other evening and on the way out noticed their pontoon display. None of their transoms had the downsweep front to rear style. They all had a verical point and a flat bottom which seems a better way to me.

 

[crb478]

Re: Motor location questions

Drop the motor all the way down, you may be surprised at how much it increases handling. You could also try a 4 bladed prop if you still have a ventalition problem. I would only change the transom as a very last resort, and even then only if it was damaged. There are several brands out there with transoms like yours. The water that comes to the motor on most pontoons is very turbulent, you need to try to get the prop low enough to get into clean water. I am assuming that you have the correct shaft lenght on your motor since I noticed the motor is newer than the boat.

 

[Fred J.]

Re: Motor location questions

CPO, As to the proper motor length, I'm not sure how that is determined. I believe mine is the 20" series. I read somewhere that seldom is the xl lengths used on 'toons.

 

[Silvertip]

Re: Motor location questions

The engne on nearly all pontoons operates in very turbulent water so dropping the engine as low as it will go will likely help. Yamaha and Merc both offer pontoon specific props so that may help as well.

 

[Fred J.]

Re: Motor location questions

My motor now sits in the water at idle along about base of the top cowling and sometimes a little below. I don't know if that's an issue. That would be with the motor trimmed all the way down, which is where I typically have to run it.