TrickyRicky
Seaman Apprentice
- Joined
- Jul 17, 2012
- Messages
- 37
I have a 1979 Johnson 55hp Seahorse
Been searching for info on a 50 hp commercial Johnson. Looking to interchange a gearcase. This gearcase in question is on *bay for a 1987 ish 50hp Johnson commercial engine (Supposedly , seller with little info). I was considering buying it for my 79 55hp Johnson. From what he says it has same input shaft splines,length and shifter rod length bolts up (but has larger gears and lower housing) and takes a prop for a 70hp 3 cylinders. Do you know if that is true? I have tried to figure it out with part number comparisons with no solid info. I think it is a 40a, 40ae, 40at, type but?
*** My questions are does it interchange? Gear ratio difference(mess WOT up)? Prop too big for 2 cyl? Bad idea ? ****
Two reasons I was considering this is my current gearcase has a slightly bent input shaft and there may be a better prop selection.
I would not want to buy the wrong gearcase. I think it is correct but I'm only a plumber! Anybody?
Tried pm DH
Been searching for info on a 50 hp commercial Johnson. Looking to interchange a gearcase. This gearcase in question is on *bay for a 1987 ish 50hp Johnson commercial engine (Supposedly , seller with little info). I was considering buying it for my 79 55hp Johnson. From what he says it has same input shaft splines,length and shifter rod length bolts up (but has larger gears and lower housing) and takes a prop for a 70hp 3 cylinders. Do you know if that is true? I have tried to figure it out with part number comparisons with no solid info. I think it is a 40a, 40ae, 40at, type but?
*** My questions are does it interchange? Gear ratio difference(mess WOT up)? Prop too big for 2 cyl? Bad idea ? ****
Two reasons I was considering this is my current gearcase has a slightly bent input shaft and there may be a better prop selection.
I would not want to buy the wrong gearcase. I think it is correct but I'm only a plumber! Anybody?
Tried pm DH