Johnson. Factory prop vs aftermarket size difference

9758JB

Seaman Apprentice
Joined
May 27, 2019
Messages
44
Hello. I have a jonhson 70 and current prop is a 13 3/8 x17. I noticed I can only find new props that are 13 1/4 x17. I figured this is a omc thing where the after market cannot be the same? Will this 1/8 inch difference show any noticeable performance issues? What about increase in rpms? Thanks
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,650
5 - 10 rpm difference if that
As said many times before, Let the Prop engineers worry about Diameter
 

9758JB

Seaman Apprentice
Joined
May 27, 2019
Messages
44
Right.. I didn't
know if it would be worth getting an Omc or trying to find one. But it sounds like its nothing to worried about
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,650
BRP makes some very good Props. They have to, if a motor performs poorly because of a Poorly Designed Prop, what going to get Blamed? The Motor, not the prop, unless the engine was run Prior with a well performing Prop.
Mercuy for years, has been one of the World Leaders in Propeller Design. I myself. run a Mercury Prop on my Volvo Penta Stern Drive, Prior to it, I used OMC Props on it.
 

9758JB

Seaman Apprentice
Joined
May 27, 2019
Messages
44
My local marina sells SOLAS props. Are those any good, or better off ordering online?
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,650
Solas sponsors this particular Forum...
Some people swear by them, other will swear at them. The Solas Props that I’ve seen, looked like Decent Props. My cousin had one on his boat, appeared to perform as well as any 3rd Party Prop
 
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