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#1
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![]() Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. |
#2
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What year and brand motor
wrote in message ps.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. |
#3
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wrote in message
ps.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. Ron Knapik wrote: What year and brand motor 1998 Mercury |
#4
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posted to rec.boats
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OK, if it was a Johnson, they make a hydrus prop specifically for pontoon
application. I'm sure merc makes something on the same line, check with a Merc dealer. Ron wrote in message oups.com... wrote in message ps.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. Ron Knapik wrote: What year and brand motor 1998 Mercury |
#6
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posted to rec.boats
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Mercury makes a bigfoot prop for pontoons
"Ron Knapik" wrote in message ... OK, if it was a Johnson, they make a hydrus prop specifically for pontoon application. I'm sure merc makes something on the same line, check with a Merc dealer. Ron wrote in message oups.com... wrote in message ps.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. Ron Knapik wrote: What year and brand motor 1998 Mercury |
#7
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FREDO wrote:
Mercury makes a bigfoot prop for pontoons "Ron Knapik" wrote in message ... OK, if it was a Johnson, they make a hydrus prop specifically for pontoon application. I'm sure merc makes something on the same line, check with a Merc dealer. Ron The Mercury Bigfoot is more then just a prop.. From the Mercury site: "BigFoot models feature greater torque, larger propellers, and beefed up drive-train components to handle the extra weight and turbulence of pontoons." Capt Jack R.. wrote in message groups.com... wrote in message groups.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. Ron Knapik wrote: What year and brand motor 1998 Mercury |
#8
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posted to rec.boats
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![]() wrote in message ... On Tue, 29 Aug 2006 22:10:11 GMT, Jack Redington wrote: The Mercury Bigfoot is more then just a prop.. From the Mercury site: "BigFoot models feature greater torque, larger propellers, and beefed up drive-train components to handle the extra weight and turbulence of pontoons." Capt Jack R. Merc put me in a 13.75x11 on my pontoon (20' with a 60) The "big foot" is nothing more than the next bigger foot for the engine in question. My 60 (same as 40 & 50) uses the 75-90 foot. It is the same as I had on my 75 Mariner, right down to the round sticker with the "13" on it. That is the old Merc foot (SAE bolts) and the powerhead is a licensed Yammy (metric) Same with my 1989 Merc/Mariner The next leg up with less gearing. The same engine RPM gives less propeller RPM and can swing a bigger propeller in size and pitch. |
#9
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OOps sorry my mistake I thought they had a prop just for pontoons on their
website. http://www.mercurypartsexpress.com/P...re=Accessories "Jack Redington" wrote in message ink.net... FREDO wrote: Mercury makes a bigfoot prop for pontoons "Ron Knapik" wrote in message ... OK, if it was a Johnson, they make a hydrus prop specifically for pontoon application. I'm sure merc makes something on the same line, check with a Merc dealer. Ron The Mercury Bigfoot is more then just a prop.. From the Mercury site: "BigFoot models feature greater torque, larger propellers, and beefed up drive-train components to handle the extra weight and turbulence of pontoons." Capt Jack R.. wrote in message egroups.com... wrote in message egroups.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. Ron Knapik wrote: What year and brand motor 1998 Mercury |
#10
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posted to rec.boats
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FREDO wrote:
OOps sorry my mistake I thought they had a prop just for pontoons on their website. I would have to look around at there site- You still might be right :-) that they have a prop just for pontoons. I just wanted to point out that the bigfoot "engines" does have some differences vs the standard 60 hp.. Cheers: Capt Jack R.. http://www.mercurypartsexpress.com/P...re=Accessories "Jack Redington" wrote in message ink.net... FREDO wrote: Mercury makes a bigfoot prop for pontoons "Ron Knapik" wrote in message ... OK, if it was a Johnson, they make a hydrus prop specifically for pontoon application. I'm sure merc makes something on the same line, check with a Merc dealer. Ron The Mercury Bigfoot is more then just a prop.. From the Mercury site: "BigFoot models feature greater torque, larger propellers, and beefed up drive-train components to handle the extra weight and turbulence of pontoons." Capt Jack R.. wrote in message legroups.com... wrote in message legroups.com... Background - Got a 21' pontoon with 40 HP 2-stroke, wasn't expecting a speed demon but was hoping I could squeeze a little more out of it. Only hitting 13 and change (GPS measured speed). Someone suggested that the prop was too big since it was only turning 5k rpms. So asked around, seemed like a 9 was the consensus. Check it out yesterday, it has a 10 on it. So I'm all excited thinking this is going to help me out... plug the numbers in the prop calculator ( http://www.boatpropellers.com/propcalc.html ), maybe 1/2 mph increase? Assuming the engine will spin up to 5500 with a 9. Sound right? I wasn't sure about 'prop slip' so I reversed it out by what I knew from current numbers. Came out to 45% and from what I read that's possible with non-planing hulls. Guess I'm also wondering if there may be more or less prop slip with the 9 vs. the 10. Ron Knapik wrote: What year and brand motor 1998 Mercury |
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