Resealing Evinrude 1961 40 hp Lark III gear case

[tommr]

My gear case is leaking and the oil is contaminated with water so I have torn it all down.
I noticed the Sierra kit only contains a single drive shaft seal.
I am not sure which direction to put it.
It seems like it would need to go flat metal side down to contain the drive shaft bushing.
It also seems like the original seal was larger or maybe there were 2.
I believe I asked somewhere and was told that the modern seals are superior to the older ones.
The main thing though, which direction for the seal please.
Thank you.

 

[F_R]

Oil seals go with the lip pointing toward the side of the fluid you are trying to contain. In this case, that would be the oil side. So, the lip points toward the oil. More modern motors have two seals back to back to seal both against the oil and the water.

 

[tommr]

Thanks for the reply.
So to be sure, the open part of the seal goes toward the oil?
The housing for the seal is beveled as if to allow the flat metal side to fit snugly.
I guess I am trying to figure out what keeps the shaft bushing from riding up and ruining the seal?
thanks.

 

[F_R]

Well, now I see you are a thinking man.....like I am. You ask a good question, and I'm not sure I know the answer. But lets start with the seal. The original one had metal top and bottom, so any contact between the bushing and seal lip would not be possible. Now the question becomes the replacement seal. Obviously it is different construction and I wonder if anybody ever considered what you are thinking about.

You are correct in thinking the bushing is free floating in there, unless it is one of the newer designs that had a pressed-in needle bearing. Whether or not it will have any tendency to float up and down, I just don't know.

The best I can offer is yes, the open end of the seal goes down. It has a garter spring in the open end doesn't it? As for whether or not the replacements they are selling now are suitable, maybe you discovered something. If you are concerned enough, try to find a NOS original seal. Part number 302545. Try my friend, Ed Elliott eddelliott@cox net. He has lots of old/obsolete parts on hand.

 

[tommr]

Thanks for the relpy.
I sent an email to Ed Elliott and I have been combing the web for more sources.

 

[tommr]

After speaking to a few people I have been informed that the drive shaft bushing #304084 is driving into the housing for a tight fit.
I bought a new bushing and while it fits the drive shaft better, and snugly fits the housing, I can still easily spin it inside the housing with my fingers.
Unless there is a way to lock this busing into place I am afraid the housing is NG. Also, on close inspection, I find the drive shaft is worn in several places. I cleaned it up with very fine emery paper but there still seems to be rings worn and polished into the shaft.

So it looks like I need a new upper gear case housing and drive shaft.

Too bad cause the motor runs nice. Starts right up and idles smoth.

 

[F_R]

Sorry, that just isn't true. It is a floating bushing, changed in 1962 to a pressed-in needle bearing.

http://s19.postimg.org/ygk02attf/img002.jpg

http://s19.postimg.org/mspy7r4oj/img003.jpg

 

[tommr]

Don't be sorry!
I really like to see things in black and white.
Thank you.
The new bushing fits like a glove where the old one would chuck a little on the shaft and in the housing.
I did get a reply from you friend and he said if he had an nos seal it could be dried out.
I think I will carefully clean the drive shaft up a bit more and put this back together with my new bushing and the seal from the kit for one more try.

 

[tommr]

I give up. I resealed the case and took it for a short spin. When I drained some oil it was milky. The only other thing that might have caused it was I used white grease to hold the pinion rear bearing in place.
I guess I have to give up on this one.