Diameter and Hub question

[roughneck1455]

Hey all

I have a question I am hoping someone can answer for me.

My current prop is a 9.9 dia x 11 pitch and I want to change to a 10.1 dia x 13 pitch. Can I use the same hub that I already have or do I need to buy a new one to go with the change in diameter?

The motor is a 25HP mercury Seapro.

 

[John_S]

Re: Diameter and Hub question

It is unlikely that you have a replaceable hub designed prop with the small outboard. You need your wot rpms with current prop. From your other post, I'd guess that going up 2" in pitch will kill your hole shot, and you top speed will probably will be close to the same.

 

[Sea Rider]

Re: Diameter and Hub question

Hub's are vulcanized to prop body, if swapping same hub to match bigger prop, work will still need to be done at a vulcanization facility.

Happy Boating

 

[roughneck1455]

Re: Diameter and Hub question

You think? I have read some post on here where there are similar setups and they are saying they get 30mph and want more. I guess I will have to try it out and see for myself. besides it does not take long to change a prop.

It is unlikely that you have a replaceable hub designed prop with the small outboard. You need your wot rpms with current prop. From your other post, I'd guess that going up 2" in pitch will kill your hole shot, and you top speed will probably will be close to the same.

 

[steelespike]

Re: Diameter and Hub question

What boat are you running? And what is your present rpm and speed.
Not knowing the year of the motor or what boat;::
If my figures are right at 6000 with a 13" prop and 10% slip speed would be about 29 mph.
And I think that kind of speed would normally be on a light reasonably fast boat.

 

[roughneck1455]

Re: Diameter and Hub question

The year of the boat is a 2010 roughneck 1455 and the motor is a merc seapro and I bought it brand new this past may but I don't think its a 2011. Not sure the year either as it is not marked anywhere.

 

[steelespike]

Re: Diameter and Hub question

Lowe site says the boat is 510 lbs thats a load,my 18' 77 Crestliner utility is only 375 lbs.
How is the performance with the 11" max rpm and speed? It may not like a 13.