Water pump weep hole

[Richard S.]

Does the 63 327 cu in engine with a 3859326 water pump have two week holes?

[Joe L.]

Re: Water pump weep hole

Does the 63 327 cu in engine with a 3859326 water pump have two week holes?

Rich------


First of all, I don't think that any 1963 Corvettes were ever equipped with a GM #3859326 waterpump. This has been discussed here before at length and I'm not going to go into it again.

As far as the weep holes go, I've only seen the 3859326 pumps with a single lower weep hole. However, it's possible some were manufactured with 2 holes. If you have such a pump, I'd say that proves at least one was so-manufactured since I cannot see any reason that anyone would add a weep hole. I don't think that 2 holes is typical, though.

[Michael J.]

Re: Water pump weep hole

My low mile early build '64, original L76 engine, undated 326 water pump has one weep hole on the bottom.

[Richard S.]

Re: Water pump weep hole

My low mile early build '64, original L76 engine, undated 326 water pump has no weep holes.

Thank you Michael for the response. Most I have seen have one weep hole. The unit I have has two. I am trying to find out if this is normal.
Rich

[Michael J.]

Re: Water pump weep hole

Sorry, I corrected it, I had to get my little mirror out and look more closely, it has one, on the bottom slight passenger side, but no others. I believe the later 326s, like late '60s, had two, one on top and one on the bottom of the shaft.

[Joe L.]

Re: Water pump weep hole

Thank you Michael for the response. Most I have seen have one weep hole. The unit I have has two. I am trying to find out if this is normal.
Rich

Rich------

Were you talking about holes on the top and bottom? Some of the pumps do have a hole at the top but I would not call that a "weep" hole and that's not what I was referring to in my previous response. I thought you were talking about 2 holes on the bottom of the pump. I don't know what the function is of the upper hole when it's present. There must be a function, though, as they sure wouldn't drill it for no reason.

For your further information: waterpumps use a carbon-ceramic mechanical seal. These seals are not perfect and a very small amount of coolant leaks by them. The weep hole is present so that the miniscule leakage can drain out. When the seal finally fails catastrophically (usually from long service or failure of the bearing), a major flow of coolant emanates from the weep hole.