New prop for my boat

[jlh3rd]

um...is that prop kinda beat up?....it looks like some of the edges are . Without being there, I can't tell....it does look like the edges can be cleaned up using a file and sandpaper.....something you can do yourself......yep, it can make a difference.....
I'd say the motor is too low. I disagree with the marina, I'd raise it. all the way...as,long as it is below the pod....start from there as it looks like it would still be below the motor pod....
my plate is about an inch+ below my pod....trying to remember...
....there are some articles that say the plate should be below the bottom of the toons......so this is not an exact science.....
....Your problem is being an hour away, and they said it would do no good .
Can you raise it yourself?.....
toons look to be the bigger ones........
Dont want to lead down a rabble hole....
If motors on pontoons are too high, you become susceptible to ventilation issues....that was my problem, I couldn't turn or trim my engine up hardly at all......just lowering it that last hole...1/1/2 - 2 " made the difference.....

 

[jlh3rd]

still want to emphasize that your not gonna get massive gains....

 

[wheelers4life]

I am going to try to lift it up and give it a try. It depends on if my cherry picker can get that high. And yes the prop is a little beat up I was doing some shallow water fishing and I bottomed out and had to use my trolling motor to get me out

 

[jimmbo]

still want to emphasize that your not gonna get massive gains....

If the Engine was Severely Underpropped, and Rev Limiter was kicking in, there will be gains as higher Pitches are utilized. How much? I won't commit to any Numbers, but we know that those higher Pitches will certainly reduce the Holeshot.
Engine Mounting Height on a Pontoon, is more like Voodoo than Standard Protocols. One pretty much has to hang over the Stern to observe the Location of the Anti Ventilation Plate.

 

[jlh3rd]

at 5800, he's not severely underpropped, he's slightly overpropped....so if he gets his 6000, or a little higher at max throttle by dropping 1inch pitch, or 1 inch diameter, or dropping one blade.......then he may be able to pull a tub'er faster.....but I'll almost...that's almost...bet his speed won't jump up...
Mine did not....doesn't mean his wont...but that's been my experience.....
but I can pull 5 teenagers on two tubes with 4 adults in the boat now, and they're not bored....
I traded speed for torque.....the only way to get more of both is to get more HP....you can't change physics....
Re-emphasizing the words "may".."might".."probably ".....etc.

his prop is banged up....I say the motor is probably too low....his marina says otherwise and won't do any good raising it...false I say....so the marina is not the most cooperative or trustworthy (my opinion)....
He says he's a newbie....that's hard because it can cost time and money, even if someone knows and understands the process of propping, motor height and other factors...he should google ventilation, cavitation, tilt/trim...
I'm curious how long his boat is...should've asked sooner...

My opinion....fix the things that are wrong and fixable.....then go "propping"
that's what I do......

 

[jlh3rd]

"I get on plane really quick but my top speed is 15mph at 5800 rpm’s"

 

[wheelers4life]

at 5800, he's not severely underpropped, he's slightly overpropped....so if he gets his 6000, or a little higher at max throttle by dropping 1inch pitch, or 1 inch diameter, or dropping one blade.......then he may be able to pull a tub'er faster.....but I'll almost...that's almost...bet his speed won't jump up...
Mine did not....doesn't mean his wont...but that's been my experience.....
but I can pull 5 teenagers on two tubes with 4 adults in the boat now, and they're not bored....
I traded speed for torque.....the only way to get more of both is to get more HP....you can't change physics....
Re-emphasizing the words "may".."might".."probably ".....etc.

his prop is banged up....I say the motor is probably too low....his marina says otherwise and won't do any good raising it...false I say....so the marina is not the most cooperative or trustworthy (my opinion)....
He says he's a newbie....that's hard because it can cost time and money, even if someone knows and understands the process of propping, motor height and other factors...he should google ventilation, cavitation, tilt/trim...
I'm curious how long his boat is...should've asked sooner...

My opinion....fix the things that are wrong and fixable.....then go "propping"
that's what I do......

I have a 21ft sun tracker bass buggy signature series.
Ok the mechanic that I talked to said on this outboard the rev limiter is 5800 rpm’s.
I found a neighbor down the street that had an 14x11 pitch 4blade prop on his pontoon almost the same boat exactly except he has a newer outboard his is a 60 ho but the prop slid right on. Still hit 5800 rpm’s but we hit 17 mph. . He’s outboard is about 4 inches higher than mine he says he gets 25 mph I don’t know about that.
On think my neighbor noticed when pulling my boat out was sloshing in my toons. It appears there is water in my toons it does not sound like a lot but it’s in there. So now I have to pump out the water. And find a weirder to seal them up. When I got home I did not see any water leaking out anywhere. I called the mechanic again and he told me to put 4 psi in the rooms and use soap water to find the leak. I have to mark them for the welder. Maybe that is another reason it’s slow but does not sound like much water but who knows.

 

[jimmbo]

at 5800, he's not severely underpropped, he's slightly overpropped....

In one sentence he is saying the Dealer told him the Rev Limiter Kicks in at 5800. Then a couple of post later, he is saying the WOT Range is 5500 - 6000.

BTW if the WOT is 5500 - 6000, 5800 is not Overpropped, in any way, shape, or form. 5300 would be.

 

[jlh3rd]

look man....in trying to fine tune his boat, and he wants to get max performance...speed and pulling.....he is SLIGHTLY overpropped !....just like I just said...

EDIT: Let's keep it civil ... Mod team

I also think his dealer is .....untrustworthy, or ignorant or whatever.....needs to find another one
specs say rpm is 5500-6000....so he is slighted overpropped!

 

[jlh3rd]

I have a 21ft sun tracker bass buggy signature series.
Ok the mechanic that I talked to said on this outboard the rev limiter is 5800 rpm’s.
I found a neighbor down the street that had an 14x11 pitch 4blade prop on his pontoon almost the same boat exactly except he has a newer outboard his is a 60 ho but the prop slid right on. Still hit 5800 rpm’s but we hit 17 mph. . He’s outboard is about 4 inches higher than mine he says he gets 25 mph I don’t know about that.
On think my neighbor noticed when pulling my boat out was sloshing in my toons. It appears there is water in my toons it does not sound like a lot but it’s in there. So now I have to pump out the water. And find a weirder to seal them up. When I got home I did not see any water leaking out anywhere. I called the mechanic again and he told me to put 4 psi in the rooms and use soap water to find the leak. I have to mark them for the welder. Maybe that is another reason it’s slow but does not sound like much water but who knows.

ok...you have more issues to fix.....I can see 2mph increase...your prop is damaged.......
understand that pontoons usually come in 3 separate sections ....each should have a plug.....mine are plastic and mounted at the top.....
It doesn't take much water to add significant weight......
I can believe he gets 25.....My pontoon is 24' and with the merc. 60 big foot it had, I was usually around 20 ....just me on board......Now with the 115 hp, I get 25+, at 5800 with the 4 blade 14x14, just me.....with the 3 blade 16x12 I got around 23 mph @6000rpm.....but I could pull 5 tubers @20+....with 4 on board.......
...I have a 4 blade, merc. 13.8x13 on the way.........see how this works......
So if max rpm is 5800, you are there except your prop needs to be fixed....or
actually maybe get one like his......
But if your pushing water in the toons, and you got 5800 and 17mph......and you solve that issue......you may find yourself over revving and going faster with that prop.....also...you may find even more speed and exceeding rpm's by raising the motor...........
everything affects everything else......
.so you could either use the throttle to keep it under 5800...and have that reserve when your tubing......or up the pitch...or whatever.......
That is what I have done......
and see where his cavitation plate is compared to his motor pod.....maybe use that distance as a starting point measurement for you.......
do NOT use more than 4psi testing the tubes.....I have been told no more than 3psi.....That's what "they" say......

get the toons fixed.......raise your motor......go out and run the boat and see where your at.......

 

[wheelers4life]

In one sentence he is saying the Dealer told him the Rev Limiter Kicks in at 5800. Then a couple of post later, he is saying the WOT Range is 5500 - 6000.

BTW if the WOT is 5500 - 6000, 5800 is not Overpropped, in any way, shape, or form. 5300 would be.

The manual says wot range is 5500 to 6000.
The mechanic looked it up and said the rev limiter on the outboard is 5800.

 

[jlh3rd]

my merc is rated for 5-6000 rpm....the rev limiter is set for rpm's after 6000, before it gets to redline or a never exceed rpm....Like any engine....
It doesn't start kicking in until after I exceed 6100...
Why would any engine maker rev limit his engine under the normal operating range as stated in the manual?.......
Your dealer has already told you moving your motor up will do no good yet your buddy's is 4 inches higher and gets 25mph?.....so that's wrong...now a mechanic says oh, it's rev limited to 5800....but normal, acceptable range is 5500-6000...ok........sorry, but, not buying it....
My 60 merc was rated the same as yours...If I went past 6100+, the rev limit would kick in.....
When these rev limiters are kicking in, the engine begins missing......
Are you saying your engine is doing that?.....if it is, then maybe your tach is wrong.....or is the adjustment off........
regardless, no one rev limits their engines UNDER the normal operating range.....doesn't happen.......
you should be able to get that engine to 6000 rpm without the limiter cutting in........

 

[jlh3rd]

the mechanic is wrong, he's bsing you.......... or your tach is wrong....
read....the...NOTE.....at....the .....bottom....

 

[wheelers4life]

My outboard does not miss at all. I will work on finding where the homes are first. Then raise my outboard.

 

[jlh3rd]

I'm not telling you what to do....
I'm giving you facts and examples from my limited experience and knowledge so you can understand how it all goes and works together so that you can make the best choices needed to spend the least amount of money......
....as good or bad as a dealer can be, regardless, if that's your only go to, you don't wanna p%ss 'em off....

so, I hope you're understanding why your motor.....assuming everything else is correct and the motor is healthy.....isn't getting to 6000 rpm....
...I hope you also understand that you don't HAVE to get to 6000....normal operating range for your motor is 5500-6000 at max throttle.....

 

[jlh3rd]

BTW...The gearcase on my '21 merc. 115 CT is a bigger diameter than a standard gearcase of the same hp......the prop has to be for that gearcase...
there's also a white, plastic ring insert to prevent ventilation from exhaust gases inside that gearcase that is susceptible to breaking and going missing......
....bigfoot = CT...

I do not know if the smaller hp big foot motors have the same considerations......just fyi...
good luck...

 

[wheelers4life]

I'm not telling you what to do....
I'm giving you facts and examples from my limited experience and knowledge so you can understand how it all goes and works together so that you can make the best choices needed to spend the least amount of money......
....as good or bad as a dealer can be, regardless, if that's your only go to, you don't wanna p%ss 'em off....

so, I hope you're understanding why your motor.....assuming everything else is correct and the motor is healthy.....isn't getting to 6000 rpm....
...I hope you also understand that you don't HAVE to get to 6000....normal operating range for your motor is 5500-6000 at max throttle.....

I understand. Now that I know that I’m not just hitting the rev limit every time I am crossing a large body of water the prop is not that big of a deal. I need to get the rooms repairs first. Last night I was looking and some idiot put a screw in the bottom of both toons. I pulled them out and lots of water came out of both toons. I looked at the top of my toons and the inspection plugs are missing. I ordered them last night. Wonder if water can be splashing up in the back rooms when going slow speeds. Thank all

 

[jlh3rd]

jeez...
most assuredly it can..........I hope you don't find more "stuff"....
I haven't had to pressure test my toons....so far all I have to do is loosen the plugs especially on a hot day and listen for expanded air to escape.....or the opposite on a colder day.....I did have a seam leak develop in one of my sections, so I used my shop vac, duct tape, a vinyl hose to fit into the drain plug hole and the blower to see exactly where the leak was.....I don't think a shop vac can develop pressure that would be too high, regardless the vinyl hose was not a snug fit....just enough to put air through any leaks...soap and water.....

common leak points are the welded seam's between sections.......and at the "M" brackets on top.........so you need to spray that soapy water all over.....


plus..having the plugs in does help prevent the toons from filling with water especially if a leak develops on the bottoms......the air in the toon has no where to go so it's hard for the water to get in .