always need to replace both water seals?

[forcenine]

A4ers,
I suppose I am succumbing to sheet laziness but is it always necessary to replace the inner water pump seal too? Is it possible that replacing only the outer one could solve the leaking? I think the outer was installed backwards.
Lisa (forcenine)

[tenders]

If only oil is leaking, obviously the inner (water) seal is working fine, but you are going to feel dumb if a water leak starts around an old seal and you have to pull the whole thing apart and replace both of them again. Especially if the act of reinstalling the shaft after replacing the outer seal messes up the old inner seal.

If you look at the outer seal right after you remove the pump from the engine and see words stamped on it...it's in backwards. The words on the two seals should face each other.

[Don Moyer]

Lisa,

Regrettably, only the inner seal relates to water leaks, and the outer seal
(at the flange end of the pump) only relates to engine oil leaks.

Don

[forcenine]

seal embarrassment

Don,
The first seal came out with the vise and screwdriver and neighbor's help but then I let my neighbor have a go at the inner seal. See pic-looks hopeless. The rubber and spring is out but pulling and banging has badly mangled the lip on both sides. Perhaps the whole lip could be torn out but then what--how to cut the ring out without damaging the core irrepairably. You can already see some damage around the hole from the pressure of the screwdriver. Would a machine shop help?
Lisa (forcenine)

[tenders]

Looks like you're almost done. Just reach in there with needlenose pliers and yank those brass pieces out. You can clean the screwdriver gouges off with a file or Dremel tool, no harm done. Make sure to remove any residual metal filings stuck to the grease on the pump so they don't score the shaft.

Reinstall a new inner seal with a vise and a socket of sufficient diameter to press on the seal but fit inside the pump. With the outer seal just squeeze it into the pump with the vise until it's flush with the surface -- don't countersink it, you might not get it perfectly straight and then it will leak oil all over your bilge. Don't ask me how I know this.

The official way to get that seal out is to take a cheap flathead screwdriver, heat it up, and bend the tip 90 degrees so you have a 1/4" protrusion to put inside the seal. Then tap it out with a hammer. This does work, and it doesn't damage the hole.

[Don Moyer]

After you get the inner seal out, be sure to use thick, well-seasoned Permatex Aviation Brand sealer around the inside of the housing prior to reinstalling the new seal. Be sure to install the inner seal with the name Oberdorfer facing out (toward the flange).

Don