Johnson 35HP 1978 lower unit seals

[TerryMSU]

Hello:
I have a 1978 Johnson 35HP with water in the lower grease. How difficult is it to replace the seals? I strongly suspect that my problem began with finding rocks on the riverbed the hard way. (damaged prop blades and spun hub). Thanks.

 

[TerryMSU]

Re: Johnson 35HP 1978 lower unit seals

Update...
I checked the lower (prop shaft) seal for leakage by putting a low air pressure on the lube fill opening and no air leakage (as shown by soap bubble test). So I decided to drain the lower unit and refill it. I only got about 10 ounces out of the lower. This seems to be a little low. Does anyone know how much the lower unit is supposed to hold?

The lube that I drained seemed to be a little thin and was definately a light greenish gray.

I also checked for any prop shaft damage (primarily checked for bent shaft). No visible indication of any bend.

I suspect that the leakage may be caused by a badly out of balance prop and so I put in new 90 weight gear oil and will check it when I get the prop back.

One possible concern is that the remains of the bad (watered down) grease may make the new stuff look bad.

Any comments would be appreciated.

Terry

 

[tashasdaddy]

Re: Johnson 35HP 1978 lower unit seals

when i get one i suspect, i fill with kerosene, or diesel, and just spin the prop several times over several hours, and then drain. replace the drain,vent plug gasket everytime they are removed.

 

[TerryMSU]

Re: Johnson 35HP 1978 lower unit seals

Bump

 

[Bobobob]

Re: Johnson 35HP 1978 lower unit seals

I just did the lower end on my '62 40hp, and I completely dropped the bottom end, degreased it and installed new seals, I also got a gasket sealant from the boat shop it was pricey but worth it I sealed everything, it was a fast drying sealant applied to both surfaces. My shop told me to also apply it to all the bolts, this just help ensure no leakage, and by leakage they ment water into the gearcase, not oil out.

As said earlier change the plug gaskets.

hope it helps.

 

[TerryMSU]

Re: Johnson 35HP 1978 lower unit seals

Well I tried the Kerosene. I don't have a can that will allow me to put either kerosene or diesel in it legally so I had to find a buddy with a can of kerosene. Flushed it with kerosene, ran it for a few seconds, and then refilled with gear lub. Will see what happens and let you all know..

Terry