The slowish leak (about 4 oz per 2 weeks) in my cooling system that I posted about a couple of weeks ago, may not be the water pump seals after all.

After crawling under the car, carefully looking at the water pump from all sides with an inspection mirror from all angles and light everywhere, I think the leak may be between the pump and the block, at the bottom, around the bottom bolt that holds the pump to the block.

That area was clearly wet this morning. And the "trail" of stain on the rib on the "snout" of the pump that I had previously thought was evidence for a failing pump seal is no larger than it was two weeks ago, and is basically dry. There is only very minimal indication of dampness near the weep hole on the bottom of the snout, less than what would come from one drop of coolant. There was a lot more fresh wetness on the block directly below the bottom pump bolt.

There are some minor signs of old, dried leakage around the big O-ring between the pump and the head. Keep in mind that the head was just removed about two months ago to replace a shot head gasket.

Should I replace the whole, only 4-year-old, pump (a genuine Volvo pump that still looks new), or just drain, remove, clean up the block, pump and head, and reinstall with new gaskets and O-rings?

Is the potential for disaster severe enough that I should rush to fix it, or do I have a week or 10 days of daily use to get a better diagnosis? Reason for that question is that I do have a Stant cooling system tester, but not the Volvo tank/cap adapters and it might take a week to get them.
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)