Yamaha 60hp to 90hp on a pontoon

MRS

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Jul 10, 2005
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Go with the 90 you will love it so will the kids. I have a 90 on a 20’er and wish I had a little more at times but is good for all I do.
 

DeepCMark58A

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Aug 17, 2015
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The transom is rated for a 100 hp motor, this also tells you a little about the size and the weight of the boat. There is no prop you can put on a 60 hp motor that will make up 40 more hp. Go with the bigger motor.
 

Sea Rider

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Sep 20, 2008
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No prop swap will convert a 60 HP motor to up 40 HP more. The only possible way to get the full 60 HP out of that motor is propping it right to run towrdards its max wot rpm range factory stated.

All boats have a max HP and max number of passengers rated for, if will
be constantly boating with much less than the max passengers allowed, don't need to go for the max HP rated for, just prop it right...

Happy Boating
 

MRS

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2,560
The transom is rated for a 100 hp motor, this also tells you a little about the size and the weight of the boat. There is no prop you can put on a 60 hp motor that will make up 40 more hp. Go with the bigger motor.
I agree I have a 20ft. with a 90hp. it works but wish I had a little more at time's. I run at 5,6oo rpm's and might get 30mph if everything is right bimin's down and running down hill. But can run 25 with top's up most of the time if the wind is not blowing to hard. 60hp will not cut it on a pontoon 20ft. no matter what prop you have on it.
 

DeepCMark58A

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Aug 17, 2015
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No prop swap will convert a 60 HP motor to up 40 HP more. The only possible way to get the full 60 HP out of that motor is propping it right to run towrdards its max wot rpm range factory stated.

All boats have a max HP and max number of passengers rated for, if will
be constantly boating with much less than the max passengers allowed, don't need to go for the max HP rated for, just prop it right...

Happy Boating

A 20' pontoon with a 60 hp motor is not going to perform to the owners desired level for the activity he wants, pulling kids on tubes. Prop has nothing to do with it.
 

Sea Rider

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A 20' pontoon with a 60 hp motor is not going to perform to the owners desired level for the activity he wants, pulling kids on tubes. Prop has nothing to do with it.
That's the OP's problem not mine, the issue is that the ones who have posted gives a you know what about wot rpm which isn't known so far and a prop maximization will better what the OP's wants to achieve. Better doesn't mean Top Performance.

Happy Boating
 
Last edited:

ahicks

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Sep 16, 2013
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That's the OP's problem not mine, the issue is that the ones who have posted gives a you know what about wot rpm which isn't known so far and a prop maximization will better what the OP's wants to achieve. Better doesn't mean Top Performance.

Happy Boating
The way I see it is that your lack of experience is hanging out.

The rest of us know that what the OP's asking for (5mph) is beyond that motors ability. That's what we are talking about. RPM and prop information simply not required to know that.

That makes prop and rpm data irrelevant. It IMPOSSIBLE to achieve what the OP want's to do as no matter what rpm he's turning, or what prop he has on it, that level of performance is out of reach - with a 60hp pontoon boat.

Speeds in the low 20's while pulling a tuber with 4 people aboard? Not going to happen. It's that simple.

Telling the OP he can put some type of prop on it that will allow him to do what he's suggesting is questionable advice. That's just as simple.....

Stay safe...
 

Sea Rider

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Amen !!!! Anyway if going for a 90 HP motor will need to prop it right for such boating requirement...

Happy Boating
 
Last edited:

johnmpcny

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Feb 5, 2021
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I have seen some mods that change carb and prop and gain extra hp. Just getting a 70hp carb replacement is less about $300 that will give you bit more with new prop maybe 3-5 mph. Not sure if I would spend the $1000 on an older motor unless I save a few thousand over buying a used 90.

HT 6084 Phase Kit 1991-2006 60 Yamaha CARBS MUST BE SENT IN ADVA​

HT 6084 Phase Kit 1991-2006 60 Yamaha CARBS MUST BE SENT IN ADVA

Click To Enlarge
  • Item #: HT 6084

HT 6084 Phase Kit 1991-2006 60 Yamaha 3 Cylinder (adds 20hp)CARBS MUST BE SENT IN ADVANCE QTY PART # DESCRIPTION PRICE 1 HT 6850 Fiber Reed $88.00 3 Main Fuel Jets $60.00 1 HT 5220 Exhaust Tuner $215.00 1 HT 8370 High Perf Head $290.00 1 6H3 Water Cover Gkt $29.00 1 6H3 Head Gkt $42.00 2 6H3 Intake Gkt $21.00 1 6H3 Base Gkt $12.00 1 6H3 Upper Case Gkt $9.00 1 HT 6300 big bore carbs $275.00
* Marked fields are required.
Qty*
Price$1,041.00
 

ahicks

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Sep 16, 2013
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Before spending that kind of money I would want to see promised/expected gains on paper with a money back guarantee. Do as you like, but I'm really doubtful that can be pulled off.

And when/if talking to these people, make sure they know you are working with a pontoon boat, not some light weight runabout.....
 
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