Johnson 40/48/50 14 to 17 spline shaft question

[racemd]

Can you take a Johnson 20" 17 spline engine shaft from a 1995 40/48/50 and use just that shaft and put it into a 1988 Johnson that currently has a 14 spline engine shaft? In looking at online stuff from boatparts.ca and TC electronics, it seems the drastic change was the shaft but everything else swaps out. They are both small loop.

 

[racerone]

Sorry----I am not sure where you are looking !!!!-----The 1995 lower unit is totally different from a 1988 model.-----There is no way that you can fit the 1995 shaft into a 1988 unit.----If you could the bigger spline on the 95 shaft would not fit into the 1988 model crankshaft.-----Totally hopeless to try and do what you are thinking.----Gears are totally different too.------You need to do better research here !!

 

[racemd]

This link shows all parts can interchange, also, i meant a 1989. They do not specify the shaft, but both are 20's and all I see different is the 89's shaft is thinner at the top with 14 splines, where the 1995 is 17 splines, the main part of the shaft's mic out the same.
http://www.boatparts.ca/johnson-evinrude-outboard/loopcharged_40_50_hp.html

 

[racerone]

I am well aware of what fits what !-----And I read 1988 in your first post !!-----So garbage in means you get garbage out !------The 95 shaft will NOT FIT in the 89 crankshaft !!!

 

[racemd]

Sorry to get you upset, I messed up what I was trying to do.. Let me see if I can clarify. I have a 95 50 small loop and I broke the clutch and chipped the 2 gears. I have a 89 good lower unit, all i was wondering is if I took out the 20" shaft from the 89 and replaced it with my 95 shaft, will that work.

 

[racerone]

I am not upset------You just need to provide correct information to get worthwhile support !!!----Yes it will.----But you have to determine what shims to use ( with the 95 driveshaft ) to put the pinion in the correct location.----A shop would have ( I do too ) the factory kit to do that.----These lower units are not robust as you found out.------You have to do the shim check or risk the lower unit to go ---BOOM----Again on you.

 

[racemd]

I was able to take the 88 40hp lower a part and I put everything used my 93 17 spline shaft with all the 88's good parts and now have working lower unit tested on a Henry O.
Thank you.

 

[webbd]

Sorry for such a late response to this.

I have a 1997 50HP and note the comment from @racerone that my lower unit is not the most rugged one out there, so this post intrigued me because I may one day find myself with a failed lower unit, and from what I see online, the older 1975-1988 lower unit is more reliable and easier to find a replacement for than the 1993+ lower unit.

If I read this thread correctly, it sounds like you have swapped an older lower unit from an 1988 model (with the 4 water inlet holes on each side) to replace a 1995 40HP lower unit (with the inlet screens on each side.)

If I continue to read this correctly, you accomplished this by removing the driveshaft from the 1995 lower unit and installing it on the 1988 lower unit, installing the correct shims to make it work.

Did I read this correctly?

Photos attached..
1998 40/45/50HP
Removed per @racerone id.

1995 40/45/50HP


70HP

 

[racerone]

The picture at the top is NOT a 1998 model lower unit !-----

 

[webbd]

The picture at the top is NOT a 1998 model lower unit !-----

Sorry about that. I got if off a Google search. I guess I got a bad pic. It's removed.

 

[racerone]

The 97 model 50 HP that you have is a 2 or 3 cylinder ?-----The last picture seems to show a 3 cylinder lower unit.-----A much sturdier unit than the 2 cylinder models !

 

[webbd]

My 1997 50HP is a 2-cylinder 737CC model and has the lower unit shown in the following thumbnail:
1995+ 40/45/50HP Lower Unit


If I read this thread correctly, the OP @racemd appears to have mounted the lower unit from a 1988 40HP onto a 1995 40HP by swapping the driveshaft.
1997 Johnson 40 pictured below.


I think I understand that the older lower units are more sturdy than the "light duty" one on my motor. I am trying to understand if I read correctly that the OP successfully swapped lower units.

 

[racerone]

The very early 50 HP motors 1971 through 1975 have stronger gearcases than the 76 through 1988 models.-------The 1989 model 40 / 48 / 50 HP to end of production are also not very robust !!----That is why the 3 cylinder gearcase was used on some of the 2 cylinder " commercial " models.