Pontoon Boat & Deck Boat Forum

Boat is a new to me 2002 22ft Suncruiser. Motor is a 2002 Yamaha 90A 2 stroke. The book says full throttle operating range is 4500-5500 RPM and max output is 66.2 (90) at 5000 r/min.

Today I was only able to get it 4900rpm at WOT after tweaking the trim. Top speed (20gps) is about what I got last time I had it out. I never paid attention to the RPM's before.

The prop is an aluminum 13.75 X 13 (pitch) It has a few nicks, but none too major. I don't feel much shake. But, I plan to replace it anyway and keep this as a spare.

Although 4900 is within the 4500-5500 full throttle range, it is toward the lower end. Would you all try another pitch?? And if so, how far would you go?

Thanks from a boating newbie...

....also add...

Not sure if normal or not, but the last inch of throttle range seemed to make no difference I could see, feel or hear. I reach max RPM with about an inch left on the stick.

I have the same toon , motor,and prop. Mine runs at 5,400 rpm and 23 mph per gps.

Is your's the white Yamaha prop? Mine is actually 13 5/8" x 13P

On the thottle issue. Mine gains rpm all the way but not much speed in the last 1,000 rpm. This is the prop I have.
http://cgi.ebay.com/ebaymotors/Yamaha-A ... iesQ5fGear

The prop on it is white and has 13.75 X 13 stamped on the side. Not sure if it is a genuine Yamaha prop or not. It is what came with the boat.

Hmm. wonder why my RPMS are lower? Could a few nicks in the prop cause that maybe?

It really doesn't take much to pop a prop out of pitch. Just the slightest smack can do it. It doesn't cost alot to rebuild them. I would do exactly what you think. Replace the current one and have it rebuilt and use it as a spare. It would be real nice if you could try a few before you buy. Does anyone around you, that you know, have a comparable prop off a 90 Yamaha or one with the same shaft size? Its kind of fun just to play with props. I do alot of it!
Good Luck!
Bryan