cam30era

I have a '65 Coupe with L76 engine. I purchased the car a couple of weeks ago, and since the weather is not conducive to enjoying the car, here in central Indiana, I've started "correcting" some things. My latest project is the thermostat bypass, or lack of the same...

At some time in the distant past, the bypass hose was removed, and the intake manifold fitting was silver soldered to close it off. So, I purchased a new intake manifold fitting, water pump (90 degree elbow) fitting, hose, and hose clamps.

Got the two fittings out with little difficulty. But here's the problem. I removed the pipe plug that was screwed into the top of the water pump. And the threaded hole is a 3/4" NPT. The 90 degree fitting is a 1/2" NPT. When I purchased the car, the previous owner told me that the water pump was not the correct one. Now I know why. I understand that one solution is to purchase a correct water pump, but I would prefer not to change the water pump, if possible.

Does anyone know if there exists a 90 degree fitting, with a 3/4" NPT and the correct nipple diameter for the hose?

Thanks, in advance, for your feedback.

vintagecorvette

You can get a threaded bushing install the busing cut off the top so it is smooth and then install the 90 degree elbow. I know of no 90 degree fitting that is 1". If you going to the effort of correcting as much as you are, why not just get the correct water pump?

oWEN

cam30era

Thank you, Owen. I didn't think of that.

I have a few other projects on my list that I want to do first. Maybe a new water pump one day.

Heading to Menards now.

investigator759

I was in the same position a few years back. Good luck finding the correct 326 water pump for under $500....

Mike Geary

The bushing you want is just a sleeve with threads on both ID and OD.

Thread it onto your elbow, then put red loctite on the bushing OD and screw it in. Remove the elbow, then hacksaw & grind off the bushing excess.

Butter it up with a little JB Weld and after paint, you have a correct 1/2"
-326 pump.

cam30era

Yikes! I had no idea.

Many thanks to everyone for all your help. The members of this forum are outstanding for help.

MikeM

What I have done in the past is to run a tap as far into the water pump threads as they'll go to open up the threaded hole for the bushing. Then, run the bushing down as far as it will go using a pipe wrench or channel locks pliers. Saw off anything that is sticking up above the pump casting.

Then, run a tap down in the bushing to open it up. Then thread in your (almost) 90* fitting.

By doing this, you'll get your (almost) 90* fitting at the correct heigth above the casting.

kskid

volvette.com has the fittings
CL039 is the 90 degree
CL039A is the adapter fitting

cam30era

I already have the 90 degree fitting, and it's installed with a plumbing adapter from Menards. Volvette's adapter looks a lot nicer. I think I'll order one. Thank you for the info.