johnson prop question - large gearcase vs small gearcase

[XoDiViAoX]

i've been trying different props on this johnson 50 i have, it's a 13 tooth spline, and i think it's a small gearcase, but i was wondering what the difference was between a large gearcase 13 spline vs a small gearcase 13 spline prop?

for instance if i bought a 13 spline prop that came off a large gearcase, would it fit on mine, but possibly mess something up, or not fit at all?

 

[oldcatamount]

Re: johnson prop question - large gearcase vs small gearcase

that's a great question! I believe the prop size is the same regardless of gear size. The gear ratio wouldn't change from a large gearcase (Bigfoot) to a small (normal) gearcase. But, having said that, don't run out and buy a new prop on just my say so. I am sure someone with more experiance will help us both here.

 

[eavega]

Re: johnson prop question - large gearcase vs small gearcase

I believe that the large gearcase props have bigger diameters, so where the the large gearcase props are in the 13"-13 1/2" diameter range, the small gearcase props are in the 11" - 12" range.

I had a 50 HP Evinrude with the large gearcase which died on me, and I found in looking for another motor that the props for other Johnnyrudes with the small gearcase all tended to be smaller diameter.

Rgds

Eric