Oversize waterpump return port

[Mike Stauffacher]

Just replaced my waterpump and found my lower radiator hose, both old and new, is much smaller then port. Appeares to be right pump L-82 350. Anyone got any suggestions? Thank you for any help. Mike

[Joe L.]

Re: Oversize waterpump return port

Mike-----

If your old radiator hose is much smaller than the lower radiator hose fitting on the pump, I don't understand how it ever worked. But, if you're saying that the size of the lower radiator hose fitting on your replacement pump is much larger than the hose diameter of EITHER the old or the new radiator hose, then I'd have to say that you have the wrong pump. All pre-84 Corvette small block water pumps use a 1-3/4" OD lower fitting. In fact, this is common to most pre-84 Chevrolets, in general. After about 1984, many of the water pumps use a smaller OD diameter lower radiator hose fitting.

If you are using a GM/Delco new waterpump, your L-82 should use GM #12522037 or Delco #251-185 water pump. If you are using something else, I wouldn't know what's correct.