Water dripping from water pump

[Gregswetka]

I have water dripping from my water pump. It does not appear to be from the impeller cover. It seems to be more from the side and bottom of the pump, (I didn’t have a mirror handy to get a good look). The engine is a 1974 vintage. What should I be looking for and what kits might I need to stop this leak and should I be concerned about repairing it now, or can it wait until the end of the season? It is about a drip every 2 seconds, and only when the engine is running.

[Al Schober]

I'm assuming this is the Oberdorfer pump, not the new one from Moyer.
If so, your inner seal is leaking. You can remove the pump (not a fun job), replace the inner and outer seals (while you're in there, do both), then reinstall the pump. Don't be surprised if you're doing the job again in another month or two, but this time you'll get smart and replace the shaft too. I've been down this rabbit hole - even converted one pump to use Parker Molythane V packings! Didn't work..
I suspect every Oberdorfer 203 pump on our engines is at least 40 years old. Correct me if I'm wrong. Anyway, the cast body of the pump wears out and the only way to fix it is to replace it. You're going to be getting a new pump sooner or later - do it now and enjoy the difference.

[capnward]

Fix it now

If the leak is not from the impeller cover, it is from the seals which are worn. The repair may be as easy as replacing the seals. This is not something you can put off indefinitely. If you let the seals get worse, they will eventually leak so much that water will be forced into the bearings, and the bearings will seize up. This could happen without warning. Then you will have to replace seals, bearings, and probably the shaft. At that point you will wish you had a new pump ready to go. You should always have a spare, like new pump on board, along with repair parts, especially seals and impellers. This scenario just happened to me with the raw water pump, and it has happened before with the fresh water pump. Another experience of mine; worn seals in a fresh water pump can also inject water into the crankcase via the accessory drive. If you are timely with the seal repair you will not need a new shaft or bearings, and the pump body should be good for many years of replacing other parts.

[JOHN COOKSON]

If the pump is leaking water onto a near by engine mount the resulting corrosion will make it impossible to adjust or easily remove the mount later.

ex TRUE GRIT