Getting correct prop for my bigfoot.......

[chrisg]

I had recently put a 60hp bigfoot on my 24-foot parti-barge, and had to put a new prop on it.

I found a prop wizard that had my parti-barge as a selection, so I entered my info for my boat, and it came up with 14/13 for water sports, and 13/15 for speed. Since this is a pontoon, I won't be doing watersports, so it sounds like a 13d ( actually 13.75) 14p is right.

I had tied putting my old SS prop on it, but found that the RPM went down to 4800 RPM. Wit a 14/13, my WOT RPM was 5800RPM.

My SS prop I found out is a 13/17, and changing from Al to SS will reduced RPMs also, which explains the 1k decrease in RPM.

The marina that first sold me the 14/13 prop has a 13/15 Al. prop on sale, thinking of getting that, putting it on before taking the boat out of the water. ( They gave me the money back for the 14/13 prop)

This should put the RPMs in the range of 5400 RPM, which is in the WOT range. That's with only one person.

So my question to you 'toon'ers is:
What reduction in RPM should I expect when the pontoon is loaded with a 60HP? ( I could see this would be where HP would have an impact on operation.)

Are there special props for toons? Does this pitch (13/15) sound right?
( And one day I hope to get a gps unit to tell how fast I'm going)

thanks

 

[Silvertip]

Re: Getting correct prop for my bigfoot.......

For pontoon service you really should have a Mercury "pontoon" prop. These are affectionately called elephant ear props as they have very large blade area. You also want a larger diameter prop with less pitch rather than a small diameter with more pitch. My suggestion is to stick with a 14 inch pontoon prop and try an 11P. Always do prop testing with an average load --not a light load.

 

[TheDude]

Re: Getting correct prop for my bigfoot.......

I had recently put a 60hp bigfoot on my 24-foot parti-barge, and had to put a new prop on it.

I found a prop wizard that had my parti-barge as a selection, so I entered my info for my boat, and it came up with 14/13 for water sports, and 13/15 for speed. Since this is a pontoon, I won't be doing watersports, so it sounds like a 13d ( actually 13.75) 14p is right.

I had tied putting my old SS prop on it, but found that the RPM went down to 4800 RPM. Wit a 14/13, my WOT RPM was 5800RPM.

My SS prop I found out is a 13/17, and changing from Al to SS will reduced RPMs also, which explains the 1k decrease in RPM.

The marina that first sold me the 14/13 prop has a 13/15 Al. prop on sale, thinking of getting that, putting it on before taking the boat out of the water. ( They gave me the money back for the 14/13 prop)

This should put the RPMs in the range of 5400 RPM, which is in the WOT range. That's with only one person.

So my question to you 'toon'ers is:
What reduction in RPM should I expect when the pontoon is loaded with a 60HP? ( I could see this would be where HP would have an impact on operation.)

Are there special props for toons? Does this pitch (13/15) sound right?
( And one day I hope to get a gps unit to tell how fast I'm going)

thanks

WOW I have a 115 4stroke on my 24ft'r and my 115 bigfoot seems underpowered! I wish I would have moved up the 150-175 class myself! I say sell or trade that 60 for a 115 minimum!

 

[rentprop1]

Re: Getting correct prop for my bigfoot.......

I have the same 60 HP Bigfoot on a 22 foot pontoon and I have a 14 x 11