Lower Unit gears

[outlawfox13]

Ok, well I know I have a bad clutch dog in my 1973 25hp Johnson, right now I swapped my lower unit from my 1968 Evinrude 18hp so I can run the 25 till its Lower unit is repaired. I found a set of gears for a 66 20hp Johnson a complete set (forward, reverse cultch dog, and drive gear) for a great price. I looked online and the part numbers dont match, but I know that the whole unit is interchangeable(as that is what I have going on now), my question is can I swap all the gears on to the 25's prop shaft and have it work just fine, or will this not work. Any input would be greatly appriciated as I would like to order these asap.

Thanks Mike

 

[F_R]

Re: Lower Unit gears

I honestly don't know the answer. But I do know that the '73 has a snap-shift clutch dog, and therefor takes a different prop shaft, with detent spring and balls. Now, whether or not the '66 dog will slide on the '73 shaft's splines, by leaving the detents out, I don't know. Depends on whether or not the spline profile is the same.

 

[outlawfox13]

Re: Lower Unit gears

awsome, thanks for the info, I will do a search to find out what years match up. Man I love this site!

Edit!!!

ok I did some research and found out that the gears are the same for these motors in this order(i only checked johnson so evinrudes may or may not vary)

25hp 20hp 18hp

71 71 71
72 72 72
73 73 73
74
75
76
77
78


incase anyone else needs this info, here ya go

 

[sutor623]

Re: Lower Unit gears

awsome, thanks for the info, I will do a search to find out what years match up. Man I love this site!

Edit!!!

ok I did some research and found out that the gears are the same for these motors in this order(i only checked johnson so evinrudes may or may not vary)

25hp 20hp 18hp

71 71 71
72 72 72
73 73 73
74
75
76
77
78


incase anyone else needs this info, here ya go

Good info!

 

[Faztbullet]

Re: Lower Unit gears

Why not just carry them to a machine shop and have forward and dog re-cut??

 

[1946Zephyr]

Re: Lower Unit gears

You can also swap the dog around too to where you have a for more years use.

 

[outlawfox13]

Re: Lower Unit gears

Thanks, those are great ideas, i was wondering if i could get them machined. I will also see if i can just flip the dog around(didnt know u could do that). Man i love this site!

 

[kfa4303]

Re: Lower Unit gears

some shops can machine the dog and/or gear. I had a shop do it for my little 10 hp and it worked fine, but I would try to find a new/donor set if at all possible. You can certainly flip the dog around, however REV may not work quite as well, but considering most of us don't use REV much, it's an ok tradeoff to make and the price ($0) is right too.