gearcase size

[txbandit44]

I am looking at getting a new prop but it seams my year and hp have 2 different sized gear cases. How do you know if you have a large or small gearcase?

 

[tashasdaddy]

Re: gearcase size

measure the diameter,

 

[mhg]

Re: gearcase size

if its akin to my 140 you also need to count the shaft splines
my 140 is the small gear case with 13 spline shaft
the large gear case has 15 spline shaft

 

[HighTrim]

Re: gearcase size

What is the model number of the aforementioned gearcase?

 

[txbandit44]

Re: gearcase size

75843c

 

[Dhadley]

Re: gearcase size

The 15" motor uses the props from 11 3/4 to 12 1/4" diameter, generally speaking. The gearcase diameter is about 3 1/2". This is the motor used in Sprint and Formula E racing but can be used on a recreational boat too.

The 20" motor uses the props that are generally in the 13 1/4" diameter. These are the same type props for the V4 motors. The gearcase is about 4 1/4" in diameter.

Look at the numbers on your existing prop. You'll need that for the pitch range anyway.