Johnson lower unite VS unknown lower unite

[snowflake1]

The silver lower unite is a 75hp 1975 johnson stinger that blew up on me.

I was going to rebuild it but the bearing on the drive shaft wore into the shaft itself making it unusable.

So, i bought another lower unite(Ebay) not really knowing much more than it came off a 75hp. The length is very close, only 1/4 shorter for the driveshaft

My problem is that the splines are not the same, where it slides into the bottom of the crankshaft.

Can something be done to make this work out. or tell me what year this Blue unite is from.


http://i314.photobucket.com/albums/ll440/snowflake2002/IMG_2754.jpg?t=1242762937


http://i314.photobucket.com/albums/ll440/snowflake2002/IMG_2755.jpg?t=1242762992


http://i314.photobucket.com/albums/ll440/snowflake2002/IMG_2756.jpg?t=1242763029

http://i314.photobucket.com/albums/ll440/snowflake2002/IMG_2757.jpg?t=1242763052




Thanks in advance

 

[Dhadley]

Re: Johnson lower unite VS unknown lower unite

We'll assume the 4 spline unit is from your motor. The unit with the multi splines is from a later model motor with a multi spline crank. Assuming it is indeed from a 3 cylinder motor. However, the splines on the multi spline shaft are very worn. If it is from a 3 cylinder motor you can put a later model crank in so the splines would match.

 

[snowflake1]

Re: Johnson lower unite VS unknown lower unite

Yes, the 4 splines is from my motor, stinger (75ESLR75) 1975 75hp 3 cylinder.


So the splines are indeed cast into the crankshaft.

Do you think all 3 cylinder 75hp crankshaft from johnson/evinrude years 1979-2003 are the same, and could be substituted for my current crankshaft?



To meet the new splines of lower unite?

 

[Chinewalker]

Re: Johnson lower unite VS unknown lower unite

They changed the crankshaft splines to the fine spline in the late 1980s - I don't know exactly which year. You would need one from a motor up to about 1986 or so...
- Scott