Good day,
What is standard prop size & pitch for a 1981 Johnson 9.9 hp ? I cant read the numbers on mine and would like to buy a spare, and any advantage in using a 4 blades prop this small kicker ?
Tx
Re: What is standard prop size & pitch for a 1981 Johnson 9.9 hp ?
The motor probably came with a 9 1/2 X 10 but your prop size would depend on the application.
especially if a heavy boat or a normal large load.4 blades can be helpfull with a heavy boat, for hole shot, and staying on plane.Also may handle better around the dock.It may reduce top speed a little.
The motor probably came with a 9 1/2 X 10 but your prop size would depend on the application.
especially if a heavy boat or a normal large load.4 blades can be helpfull with a heavy boat, for hole shot, and staying on plane.Also may handle better around the dock.It may reduce top speed a little.
I may want to try the benefits from thoses avantages with a 4 blades prop. Considering I am happy with the 9 X 10 3 blades, should I stick with those numbers in choosing a 4 blades prop ? or is this a totaly new calculation ? Tx
Re: What is standard prop size & pitch for a 1981 Johnson 9.9 hp ?
Without your present rpm and speed you really shouldn't make any prop changes.
Something like a tinytach and a gps could get that info. An optical tach might work too.
Usually on larger motors it is suggested to drop an inch in pitch when going to a 4 blade.
I'm not sure with smaller motors and we don't know where your rpm is now.
