1968 20hp Johnson gear leak

[kburks]

HELP!

I inherited a 1968 Johnson 20 hp outboard motor. The water pump was not working. I replaced the impeller and lower unit seals. While running the motor blows gear oil up and out past the drive shaft seal. I have replaced the seal twice with no luck. There is some wear on the shaft from age. Could it mean I will need to replace the drive shaft. I hate to spend the money for a new drive shaft and it still leak.

Ken

 

[Mas]

Re: 1968 20hp Johnson gear leak

There is some wear on the shaft from age.

If there is any pitting where the shaft contacts the seals, it will be hard for it to seal properly. When you say "wear" what exactly do you mean. Also, check to make sure that the seal is not backwards.

MAS

 

[kburks]

Re: 1968 20hp Johnson gear leak

There is pitting. I have a spare shaft and it is pitted and leaks also. I tried filling the pits with JB weld and sanding off the excess, with no success. How do I tell if the seal is in upside down ? It has room for two seals. Any tips on where to buy a new drive shaft ? Since the motor is so old I considered having the the shaft machined.

Ken

 

[Mas]

Re: 1968 20hp Johnson gear leak

I am not familiar with your exact motor, but I do know the seals can be reversed and not work as intended. Looking at the diagrams from

http://www.evinrude.com/en-US/Accessories/Literature

(follow the links to your exact motor.)

It looks like your motor only has one drive shaft seal.


The prop shaft and drive shaft on my motor for example has two seals that are installed back to back in opposite orientation...one to keep lube in and one to keep water out.

MAS