New prop for my boat

[wheelers4life]

I have a 1996 sun tracker bass buggy signature series pontoon boat. I purchased used.
It did not have a prop on it when I got it.
It has a mercury 50hp 4 stroke Bigfoot outboard.
It is the one that basically has a Yamaha block and mercury everything else. It is a carved model with 4 carbs. Using the manual I purchased a 4 blade mercury split fire 13.8 10p prop. I get on plane really quick but my top speed is 15mph at 5800 rpm’s. Great for fishing no problems at all. But my son is 9 and wants to go on a tube. Is there a prop I can buy to give me more top end speed to pull a tube. I tried to pull it with this boat and it was pretty slow going. I forgot to look at the speed but my son was bored pretty quick. I would also like to speed up to get across larger bodies of water. On of my fishing spots is about 10 miles away from the doc and it takes forever to get there at 15. Thanks

 

[jimmbo]

Normally I would say; No. Changing the prop is not going to give you any more speed. For that you need more power.
That said, what is the WOT Rpm range for that Engine? If you are under propped, then an increase in pitch will bring down the Rpms and might give you another 1/2 - 1 mph more top speed

 

[airshot]

Due to their design, pontoons take a lot of Hp to create speed....doesn't seem like it should, but that is the way it works. If you see pontoons pulling tubers and other toys theyvhave big engines!! Near me there is a family with a big toon, three logs, probably 28 ft long, and they pull toys all the time, but he has twin 300 hp Mercs hanging off the back....he claims about 40 mph wot...

 

[wheelers4life]

Normally I would say; No. Changing the prop is not going to give you any more speed. For that you need more power.
That said, what is the WOT Rpm range for that Engine? If you are under propped, then an increase in pitch will bring down the Rpms and might give you another 1/2 - 1 mph more top speed

The WOT is 6000 I was just wondering because another boat just like mine with a ho hp was running at 25 mph and we have almost the same boat

 

[wheelers4life]

Due to their design, pontoons take a lot of Hp to create speed....doesn't seem like it should, but that is the way it works. If you see pontoons pulling tubers and other toys theyvhave big engines!! Near me there is a family with a big toon, three logs, probably 28 ft long, and they pull toys all the time, but he has twin 300 hp Mercs hanging off the back....he claims about 40 mph wot...

My boat is only set up with a max hp of 90. And I was thinking that another 10k for maybe a few mph is not worth it. I had thought maybe my outboard was bad took it to the shop and they said it was in great shap. carbs a re tuned and adjusted and the compression is 120 on all 4.

 

[Regal30]

I have a 1996 sun tracker bass buggy signature series pontoon boat. I purchased used.
It did not have a prop on it when I got it.
It has a mercury 50hp 4 stroke Bigfoot outboard.
It is the one that basically has a Yamaha block and mercury everything else. It is a carved model with 4 carbs. Using the manual I purchased a 4 blade mercury split fire 13.8 10p prop. I get on plane really quick but my top speed is 15mph at 5800 rpm’s. Great for fishing no problems at all. But my son is 9 and wants to go on a tube. Is there a prop I can buy to give me more top end speed to pull a tube. I tried to pull it with this boat and it was pretty slow going. I forgot to look at the speed but my son was bored pretty quick. I would also like to speed up to get across larger bodies of water. On of my fishing spots is about 10 miles away from the doc and it takes forever to get there at 15. Thanks

Are you sure that you're not hitting the rev limiter? 10p seems small to me. My last pontoon was 22ft with a 17p factory but I could also run a 19p with no problems. Go to your prop shop that you use and ask if they have a couple of used props in different pitches and diameters to try out. You might be able to go smaller dia. and up in pitch. Hope this gives you some ideas.

 

[wheelers4life]

I wish I could. I only have tracker boats and they are no help. They sold me this one. The do not have anything to try out. I hate being in a small town. I have called every shop within a 1 hour drive and get the same answer. No props to try out and if I install it it’s mine. This makes no sense to me . I could see if it was damaged but if I use it for a few minutes and send it back I should be able to exchange it.

Are you sure that you're not hitting the rev limiter? 10p seems small to me. My last pontoon was 22ft with a 17p factory but I could also run a 19p with no problems. Go to your prop shop that you use and ask if they have a couple of used props in different pitches and diameters to try out. You might be able to go smaller dia. and up in pitch. Hope this gives you some ideas.

what outboard was on yours maybe I might just say heck with it and try out a 17 or so

 

[wheelers4life]

I have seen other with a 60hp that have a 13 pitch maybe i can try that

 

[jimmbo]

Are you sure that you're not hitting the rev limiter? 10p seems small to me. My last pontoon was 22ft with a 17p factory but I could also run a 19p with no problems. Go to your prop shop that you use and ask if they have a couple of used props in different pitches and diameters to try out. You might be able to go smaller dia. and up in pitch. Hope this gives you some ideas.

He says max is 6000rpm, and he is only at 5800... I have no idea what the Rev Range is on these 4 Strokes, so I hope he was accurate

 

[wheelers4life]

He says max is 6000rpm, and he is only at 5800... I have no idea what the Rev Range is on these 4 Strokes, so I hope he was accurate

I spoke with a mercury technician and he said the rev limiter is 5800 rpm and I needed to at least move up to a 12 pitch. When I read the manual it says pontoon us a 11 pitch but for boats that is under 3000lbs use a 13 pitch. My pontoon is 2300lbs. I do not know I am confused it I go up to an 11 I do not thing that will be much of a difference and I do not have a prop shop around here.

 

[jimmbo]

So what it the WOT Rpm Range for your motor? 5000-5500, 4500-5500?
Try the 12, will bring the Rpms down, if it doesn't an you are still hitting 5800, you have to add more Pitch.
As for the 3000lb vs, your 2300lb. I will assume the 3000lb was referring to non-pontoon boats. What works on Conventional Hulls, is not what Pontoons require

 

[harmanoff]

I bought a 02 mercury bigfoot and 28ft boat from a older fella who is no longer cabable of boating (sad) and the motor had a 13p prop on it. The mercury dealer i spoke to to get an idea of prop size since i put it on a jon boat, said the 13p prop is a pontoon prop made for pushing if that helps any!

 

[wheelers4life]

So what it the WOT Rpm Range for your motor? 5000-5500, 4500-5500?
Try the 12, will bring the Rpms down, if it doesn't an you are still hitting 5800, you have to add more Pitch.
As for the 3000lb vs, your 2300lb. I will assume the 3000lb was referring to non-pontoon boats. What works on Conventional Hulls, is not what Pontoons require

wot is 5500 to 6000

 

[jimmbo]

I spoke with a mercury technician and he said the rev limiter is 5800 rpm and I needed to at least move up to a 12 pitch. When I read the manual it says pontoon us a 11 pitch but for boats that is under 3000lbs use a 13 pitch. My pontoon is 2300lbs. I do not know I am confused it I go up to an 11 I do not thing that will be much of a difference and I do not have a prop shop around here.

In one post you say the Rev limiter is 5800

then you say the WOT range is 5500 - 6000

wot is 5500 to 6000

So which is it?

 

[jlh3rd]

I have a 1996 sun tracker bass buggy signature series pontoon boat. I purchased used.
It did not have a prop on it when I got it.
It has a mercury 50hp 4 stroke Bigfoot outboard.
It is the one that basically has a Yamaha block and mercury everything else. It is a carved model with 4 carbs. Using the manual I purchased a 4 blade mercury split fire 13.8 10p prop. I get on plane really quick but my top speed is 15mph at 5800 rpm’s. Great for fishing no problems at all. But my son is 9 and wants to go on a tube. Is there a prop I can buy to give me more top end speed to pull a tube. I tried to pull it with this boat and it was pretty slow going. I forgot to look at the speed but my son was bored pretty quick. I would also like to speed up to get across larger bodies of water. On of my fishing spots is about 10 miles away from the doc and it takes forever to get there at 15. Thanks

I had an '05 merc. 60 hp, 4 stroke big foot on my 24' pontoon...
rpm range was 5-6000....the rev limiter kicked in at around 6100+
....I'm sure yours is the same......but regarding your question....
you can't have both...it's a compromise.....
props aren't magical. You're already close to max rpm, if you luckily get a prop that gets you to 6000 rpm at max throttle, you will keep a higher speed when pulling that tube, but will probably lose top end speed when not carrying a load......regardless, we are not talking major increases..just tweaking.....
....it's already been stated, bottom line, you need more hp..

I can show hard facts concerning propping and results for my 115 hp merc vs my previous 60 hp merc. Although almost doubling my hp, improvements are satisfying but not substantial.....and it cost me $8000......
....things to think about....

 

[wheelers4life]

I’m looking for a few more mph and I want the right prop for my boat. I took it to a marina about an hour away. They did not have any props in stock for my boat but he did say that my cavitation plate was way too low and lifting my outboard a few holes would not help. That I needed to reposed with a 20” outboard or put a jack plate on the boat with an 8” lift. I did not have time last night to look at jack plates. I’m new to boating, but he said he thought my boat has been repowerd with an outboard that was to long.

 

[jimmbo]

I’m looking for a few more mph and I want the right prop for my boat. I took it to a marina about an hour away. They did not have any props in stock for my boat but he did say that my cavitation plate was way too low and lifting my outboard a few holes would not help. That I needed to reposed with a 20” outboard or put a jack plate on the boat with an 8” lift. I did not have time last night to look at jack plates. I’m new to boating, but he said he thought my boat has been repowerd with an outboard that was to long.

Pictures, taken from the side, Level, not pointing Up or Down, taken of the Relationship between the Prop and Hull Bottom.

 

[jlh3rd]

I’m looking for a few more mph and I want the right prop for my boat. I took it to a marina about an hour away. They did not have any props in stock for my boat but he did say that my cavitation plate was way too low and lifting my outboard a few holes would not help. That I needed to reposed with a 20” outboard or put a jack plate on the boat with an 8” lift. I did not have time last night to look at jack plates. I’m new to boating, but he said he thought my boat has been repowerd with an outboard that was to long.

those pictures above are correct ..for a planing type hull...but the problem you ...and I ...have/had is that we are dealing with a pontoon boat....not a planing hull or flat type...or even a V hull.....so it gets...complicated to a newbie...and tough to explain on a forum.....they do illustrate the basic principle involved in correct motor height ....
.....we need to see a picture of your motor level and in relation to the motor pod/ mount...AND....in relation to one of your toons.....
I can tell you that after adding my new 115hp merc. I had to lower it to the last position ( 1/1/2") ....and it cured my ventilation issues......but cost me a little speed.....so lowering my motor just a little helped tremendously........so I disagree with the marina's assessment...but I am not there.....
My new motor is a long shaft....yes, motors can come in long shaft/ short shaft designations.....and most pontoons need a long shaft motor.....
...you said you are new....so.....understand. You are only 200 rpm away from max rpm....A 1 inch decrease in pitch....or a 1 inch decrease in prop diameter......or a decrease in a blade (4 to a 3, keeping the same diameter and pitch)...will bring up the rpm's.......
that does NOT mean your speed will increase........
.now, more stuff...
...so, the lower a motor is in the water, the more drag therefore lower speed...
you see where this is going........so , IF your motor is in fact too low (send pics).....Raising that motor to a proper position might actually solve all your issues without changing props....it might........
point is....every change made affects everything else....to me, having the motor at the correct height should be first.....

first hand experience:
my 4 blade 14x14 gives me about 25 mph but only 5800 rpm max....when pulling kids on tubes, rpm would max at 52-5300 and speed maybe 18 mph...
the 3 blade 16x12 ( i just destroyed) gave me around 23 mph at 6000 rpm's....I could go higher but I'd be overrevving......but it let me pull tubes full of kids at 57-5800 rpm's with a speed of about 20.....
you can have one or the other.......to get both, you need HP...
oh...need to add....what size are your toons?...mine are 25" diameter which makes a huge difference....
a 1996 might, and probably does, have smaller diameter toons....not what you wanna hear....but proper height and correctly propped motor might work for you......

 

[wheelers4life]

This is a photo I took last night when I was going to do some research but when I went in I just went to bed.

 

[wheelers4life]

Well the jack plate is not going to work I will not have enough play in my steering cable. I will just have to lift it up. I attached a picture of my water level