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post #18 of Old 01-29-2011
Learning the HARD way...
eherlihy's Avatar
Join Date: Jan 2007
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OK - I've rebuilt and reinstalled the pump, and thought that you may be interested in learning from my experience.

Here is an exploded diagram of the pump for reference;

First off; despite what I suspected earlier, my pump did need rebuilding. The outer lip-seal [#8] (the one that seals the water end of the shaft) was leaking, not bad, but it needed to be fixed.

I made the tool recommended in the earlier post from a " allen wrench. I found that the tool was useless. Instead, I used a hammer and a 12d common nail to pound the seals out. I placed the pump engine side down on a block of wood, and pounded away. I slid the shaft out of the pump, inserted the nail, head down, into the pump, engaged the head of the nail on the top of the seal, and pounded down on the point of the nail. I kept re positioning the nail around the seal, and out it, eventually, popped. Note that if you try this, that your follow through with the hammer stroke makes all the difference.

If I were to try this again, I would make some kind of press to draw the seal out. I believe that I could do this with a piece of wood, a 4" long bolt, 3 nuts, and some washers. - Next time...

My attempts to remove these seals, with both the allen tool, and the nail, had the consequence of completely buggering the carbon bearing [#12] . Fortunately, as you know from my earlier post, I had purchased the major rebuild kit, which included one. To remove the carbon bearing, there is no way, other than to use some form of press.

I am fortunate in that my vice opens just wide enough to hold a " block of wood, the pump housing, and a Craftsman 3/8" drive 16mm socket. I positioned the socket in the pump housing with one end against the bearing, and the other end sticking out of the pump housing. I positioned the block of wood in the vice, and then positioned the pump/socket against the block of wood in the vice. The socket touched the face of the jaw of the vice, and the pump housing touched the block of wood. I then tightened the vice, taking care that nothing slipped out of alignment. As the bearing slowly pushed deeper, and out of the pump housing, I needed to swap the standard 16mm socket for a deep socket.

After I had the pump body completely stripped, I cleaned the face where the cover mounts up with a file, and cleaned where the Lip-Seals sit with some steel wool. There was a fair amount of corrosion (green) in here. I then polished the areas that I used steel wool with a brass brush inserted in my dremel. Finally, to help insert the new bearings and seals, I coated the inner surfaces, and the lip seals, and the bearing with molybdenum disulfide grease.

I reassembled the pump, again using the vice as a press and various sockets to insert the new carbon bearing, and the new Lip-Seals. As I recall, a " drive 3/4" socket was used to press the Lip-Seals.

Hope this helps!
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