1975 Chrysler 20hp Lower Unit Oil Seal problem

[dubfab]

 

[dubfab]

Re: 1975 Chrysler 20hp Lower Unit Oil Seal problem

In the picture above is the seal below the water pump. I recently replaced the seal with brand new one, i replace all the seals on the lower unit. BUT when i put it all back together to put the gear oil in it. i noticed that when i put the oil in the top screw hole, when i put the oil in, i notice it leaking from the seal below the water pump. Its leaks around the drive shaft, should a new seal let that happen? The seal in question is brand new and went in with no problems, i am at a lose for words. Any ideas out there?

 

[jerryjerry05]

Re: 1975 Chrysler 20hp Lower Unit Oil Seal problem

Look at the drive shaft? Is there a groove in the shaft?
Can you get the seal out again with out destroying it? Looks like it might be in upside down??
Sometimes a groove gets worn in the shaft.It can be gotten around,put a couple of shims under it and lift it up.
A couple of thousands should be enough or try flipping the seal around.

 

[dubfab]

Re: 1975 Chrysler 20hp Lower Unit Oil Seal problem

well there was a groove in the prop shaft, i did take care of that and used extra fine sand paper to it. But the seal below the water pump, shown in picture, has the small (compression spring) around the inner part of seal, i never thought it could be installed upside down.

 

[dubfab]

Re: 1975 Chrysler 20hp Lower Unit Oil Seal problem

The seal in picture has the SPRING side facing up. Could this be installed the wrong way?? i will try to take seal out and flip it around see what happens.

 

[jerryjerry05]

Re: 1975 Chrysler 20hp Lower Unit Oil Seal problem

Usually the spring side is hidden from view.
The groove is what causes the leak.It needs to be filled or the seal installed on a different spot?
I had a Mercruiser sterndrive the prop shaft was worn and had a groove.I used marine tex fiberglass filler and put it in a lathe.Turned it and smoothed it with 1200 sandpaper.Worked for years.

 

[dubfab]

Re: 1975 Chrysler 20hp Lower Unit Oil Seal problem

ok i found the problem with the drive shaft oil seal under the water pump. When i was replacing all my oil seals i had all the parts, new oil seals, layed out on work bench. As i was replacing them one by one i didn't notice that i used the wrong oil seal, i used my extra prop shaft seal for the drive shaft, the prop seal was bigger i checked it with a guage not by much. So pulled out the wrong seal and used the EXTRA one i didn't know where came from. Put the extra one in, filled LU with oil, put back on motor, put in water and ran it for 5 minutes soild, stopped and checked the oil. NO water was in LU not even a drop. The oil had the little bubbles in it from checking it right after i ran it but no water- oil was ok. So lessons learned is that to always check your parts, list them, work by doing one task at a time, remove old parts from your work bench and maybe you won't have a situation like mine.