View Full Version : Water Pump Problems

10-04-2017, 11:59 AM
I purchased a brand new water pump from Macs and the bypass hose connection on the new pump is 7/8" instead of the 5/8" that was on the original pump. I called Mac's and they said all of their pumps have the 7/8" fitting. Is there a Ford that used a 7/8" bypass? Does anyone know if the fitting can be removed and easily replaced? It looks like it is pressed into the water pump housing. The fitting on the new pump is a "flared" fitting where it looks like where it connects to the pump it would fit a 5/8" tube.

10-04-2017, 12:23 PM

Most of the water pumps came with a 5/8" outlet pipe. However some of the 1958 & 1959 intake manifolds had a 7/8" pipe instead of 5/8". The pumps would come with a rubber spacer to make up the difference. You can put a rubber spacer (smaller diameter hose) on the intake pipe and just use a 7/8" or even a 3/4" hose instead of modifying the pump.


10-04-2017, 12:55 PM
Thanks John.
I figured something like that would have to work. I've never seen any of the 7/8" bypass fittings, so that took me by surprise.
I was able to find this and ordered the hose. I figure the silicone hose should outlast the pump. Thought I would pass it along to give a heads up if they are changing a pump. Seems our only option on these pumps are the new ones from TBird houses which are made in China.

10-04-2017, 01:49 PM
Seems our only option on these pumps are the new ones from TBird houses which are made in China.

It appears that Cardone is not rebuilding these pumps any longer. I imagine good cores are getting harder to find. As you said we're at the mercy of whoever is making new ones. At least they're still available. Thanks for the heads up on the hose.


10-04-2017, 05:21 PM
One solution would be to put a short piece of 5/8" over the intake fitting. Then put the 7/8" piece over the pump and the 5/8" piece

10-05-2017, 12:14 AM
that fix worked fine for me. You don't have enough room
to do much else.