Need Suggesstions with Outboard Motor Height.

[72charger]

so... here goes again another dreaded is my motor set in the right height and is my prop inadequate questions. lol.

i have a 1995 Grumman 20ft funship pontoon -
i think the pontoons are 24in maybe 25in.

the boat came with an evinrude 50 2-stroke VRO
i removed that engine due to different running issues.

i replaced the evinrude with a Yamaha 60 4-stroke with a 20in shaft
the prop was the same prop i ran the 60 with on my 17ft Xpress with an HD hull.
The Yamaha 60 is mounted as per the motor rating plate on the trasom.
it is mounted in the 2nd hole which raised the motor 1 notch off the transom

with me and 1 passenger in the boat i get about 17mph at 3800 RPMs.
if i trim the motor it does different things but the RPMs do not really change.

so... should i raise the motor another notch or do you think a different prop made for pontoon boats do me better.
this yamaha should be able to reach approx 6000 RPMs.

it seems to burn a lot more fuel than when it was on my Xpress (and im sure its the added weight of the boat)

i just feel i can get more out f this motor than im currently getting.

i have thought of going with a larger motor since this pontoon has a rating of a 115hp.

what are yalls thoughts...

any help or suggestions would be appreciated.
Thanks
Anthony

 

[Jeep Man]

Re: Need Suggesstions with Outboard Motor Height.

It appears that your height is correct. What is not right is your prop pitch. You will burn fuel and shorten the life of your motor. Whatever your pitch is, you will likely have to drop by 4p, so if you have a 17p try a 13p. If it's a 15p try an 11p. You should be getting 20-21 mph with 1 or 2 on board,

 

[72charger]

Re: Need Suggesstions with Outboard Motor Height.

update: it rained all day friday and i was off from work so i was unable to get to the prop shop. might be a lil bit before i can get there again. rain has been killer these last couple of weeks here in South LA. thanks for the tips and i'll let you know how it all turns out.

might have a source for a 90hp yamaha and i know of a 100hp 4-stroke for sale for a good price im going look at this weekend.
just feel the need for more speed in the pontoon but at what cost---- more fuel im sure and not too sure i want to go that route. i guess i just need to accept the fact that pontoons or at least my 95 grumman isnt perfomance oriented. lol

 

[lncoop]

Re: Need Suggesstions with Outboard Motor Height.

With a twenty inch shaft I doubt you can raise it any. If you can swing it I'd go with a bigger power plant. Your fuel consumption will probably increase, but not as much as you think. Four strokes consume less fuel than two strokes, and since you'll have a bigger motor you won't feel compelled to open the throttle as wide for cruising. What happened to the Xpress?

 

[72charger]

Re: Need Suggesstions with Outboard Motor Height.

yeah man...im thinkin a 90hp would be plenty for what we do with it. cruise around and go out to the lake and chill at the sand bar. im not a small guy by any means so with me and my wife with a SMALL ice chest its going 3800 RPMs max and about 17 Mph. with 6 people on the boat including myself im doing 3800 RPMs and 12-13 mph... i just think i need more speed... but with a prop change im anticipating that will get better.

when i put the 60hp on the transom plate had instructions on where to mount for what particular size engine you would be installing. i was amazed that it had a suggestion for a 115hp placement so i assume its rated for a 115hp.

i have talked to someone i know about a 90hp that i may just buy from them and put on the pontoon... we dont travel very far from the camp but it can sometimes be about 12-15 miles or more on a good cruise day with some bar hoppin included. i can swing the price for sure and the 90 only has about 30hrs on it. and if that works out i'll put the 60 back on the Xpress.

Incoop you asked "What happened to the Xpress? "... Well i still have it. and it was the only boat i had at the time. we bought a camp and now that we are having more visitors everyone wants to go for a boat ride and I can only take 3 and myself in my 17ft Xpress. its set up for fishing... so we got a SWEET deal on this pontoon and decided we'd just put the 60 off the Xpress for the summer and see how much we use it... well we use it soooo much that its going to stick around and i miss the quick ride of the Xpress...

 

[lakegeorge]

Re: Need Suggesstions with Outboard Motor Height.

so... here goes again another dreaded is my motor set in the right height and is my prop inadequate questions. lol.

i have a 1995 Grumman 20ft funship pontoon -
i think the pontoons are 24in maybe 25in.

the boat came with an evinrude 50 2-stroke VRO
i removed that engine due to different running issues.

i replaced the evinrude with a Yamaha 60 4-stroke with a 20in shaft
the prop was the same prop i ran the 60 with on my 17ft Xpress with an HD hull.
The Yamaha 60 is mounted as per the motor rating plate on the trasom.
it is mounted in the 2nd hole which raised the motor 1 notch off the transom

with me and 1 passenger in the boat i get about 17mph at 3800 RPMs.
if i trim the motor it does different things but the RPMs do not really change.

so... should i raise the motor another notch or do you think a different prop made for pontoon boats do me better.
this yamaha should be able to reach approx 6000 RPMs.

it seems to burn a lot more fuel than when it was on my Xpress (and im sure its the added weight of the boat)

i just feel i can get more out f this motor than im currently getting.

i have thought of going with a larger motor since this pontoon has a rating of a 115hp.

what are yalls thoughts...

any help or suggestions would be appreciated.
Thanks
Anthony

We had a 2006 22ft Sweetwater with the 60hp 4 stroke Yamaha and it ran 21mph by gps. I think it had a 14 x 11 prop, but not positive. Call Yamaha and ask them what they recommend or go to their website and look at their test results, they test all their motors with results on many different boats.

That motor on a 20ft toon should run approx 23/25 mph.

 

[Silvertip]

Re: Need Suggesstions with Outboard Motor Height.

To save yourself a lot of anxiety and guesswork, go to Yamaha's web sit and click on PERFORMANCE BULLETINS. There you can look at performance test for virtually any combination of boat, engine, and technology (2 or 4-stroke). You enter the engine type and HP, pick a boat (one similar to yours if your exact boat is not listed) and then click the performance report for that boat. They list speed at RPM, fuel consumption, weights, and most important -- what prop was used for the test. For a pontoon, on a 60 yamaha I too would guess you are in 14 x 11P territory. Yamaha does make a pontoon specific prop with big rounded ears. They work better in reverse than a standard type of prop as well. If your 60 worked fine on a V-hull it is no wonder it doesn't perform on a pontoon -- they both require very different props.

 

[72charger]

Re: Need Suggesstions with Outboard Motor Height.

UPDATE!! I've installed the 90hp 4 stroke and a 14 x 13 prop and at 5800 rpms with 2 people on board we got to 28 mph...i am very pleased. when i bring the toon back to dealer after my 10 hr break in on the motor i may go with a 14 x 11 prop so when the boat is loaded we still get plenty of power... thanks to all for the suggestios... much appreciated... now to work on a sound system...