Is my pontoon going max speed

R

Ron U

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Jun 17, 2013
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I am enjoying my 28' Party Hut. It is long with a hard top, lots of seats, a middle toon most of the length of the boat, etc. It is heavy. It has a 90 hp Mercury. I can only get 8-9 mph out of it according to my GPS. The tach tells me the motor is only revving a max of 3100 rpm. Does this sound normal? Once again, I know it is heavy. Perhaps I just need a much bigger motor?
 
matt167

matt167

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Sep 27, 2012
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Re: Is my pontoon going max speed

You need to prop it correctly but I doubt you will go any faster.. 90hp on a 28' hard top toon is good for displacement speed but not planing speeds. You probably need dbl that to get decent speed out of it
 
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calvinator

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Sep 22, 2010
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Re: Is my pontoon going max speed

You have some upside....
Your RPMs too low. I don't know your outboard, but RPMS should be 5000+ RPM. Check into the pitch of your prop. Should be 11" or 13" pitch for a big pontoon.


I had a 60HP Merc with 11" pitch prop on my 30' pontoon w/sundeck and was @ 10MPH. I now have a 150HP Merc and I see 28-30MPH on flat water no wind. Just to give you a range.
 
MH Hawker

MH Hawker

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Re: Is my pontoon going max speed

I get 12 mph on a 20 foot with a 15 hp
 
5150abf

5150abf

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Re: Is my pontoon going max speed

Your engine isn't running right, 3100 isn't right even under a huge load.

I would start there, even if the engine is propped way wrong it should turn more rpm than that, get ti tot a shop or break out the wrenches.
 
airdvr1227

airdvr1227

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Re: Is my pontoon going max speed

Definitely either a problem with the prop or the motor.
 
Okieboatguy

Okieboatguy

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Re: Is my pontoon going max speed

The prop is definitely mismatched. You should be getting, like Calvinator stated, around 5000+ on your rpms. What is your current pitch? I am running a 14.5" 3 blade with a 17 pitch on my 21' tri-toon, and I run at 35-37 mph on the gps. I know when I had some work done on my boat and the dealer put on a 15" 15 pitch because that is what Mercury recommended for a pontoon, and I pegged out the rpm's and had a max speed of 22. Keep in mind a tri-toon will perform differently than a standard pontoon. You should be able to call Solas and consult them and they can help you get the right pitch. This all assuming that there is no issue with your motor of coarse.
 
B

Bamaman1

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May 15, 2011
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Re: Is my pontoon going max speed

You'll probably need to go with the lowest pitch prop you can get. Find yourself a good prop shop, as their advice is free when you buy from them.

Sometimes you've got to get'em setup right, and then just live with the limitations of what you have. Such a boat will never run very fast.
 
The Rooster

The Rooster

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Re: Is my pontoon going max speed

Ron U said:
I am enjoying my 28' Party Hut. It is long with a hard top, lots of seats, a middle toon most of the length of the boat, etc. It is heavy. It has a 90 hp Mercury. I can only get 8-9 mph out of it according to my GPS. The tach tells me the motor is only revving a max of 3100 rpm. Does this sound normal? Once again, I know it is heavy. Perhaps I just need a much bigger motor?
Click to expand...


Ron, somethings not right. Try to confirm your tach is reading properly. Just for reference, friends of ours have a 30' Party Hut w/ Merc 115 Optimax. With a normal load they run 18 - 19 mph around 5700 rpm. Normally cruise 13 - 14 mph @ 4000 + rpm. Good luck !!!
 
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