Finally had time to work on the Dart on Monday. Had some extra heater hose and bought some all-thread to plug the pump. Forgot my keys at my house so I didn't have time to start it. I'll play with the car on Saturday, a little.

Went to my mom's house to work on the Dart. I started it up and it was still leaky through the threads of the all-thread which I figured. So, I decided to throw in the towel and get a rubber cap like I had before. I went to the local Autozone, which has been pretty good to me, but they didn't have anything. So, I decided to go to the local Ace Hardware to see if they had a 3/4" bolt as all Home Depot had was 3/4" all-thread. I got to Ace and they didn't have anything more than 1/2". Ironically, right next to the bolts, I found these tapered rubber plugs for $0.40-0.60. So, I bought a couple and went home. I got the wrong size, so after lunch, I went back and got one size smaller and came home. So, I took the heater hose and all-thread off, placed the plug on the water pump, reinstalled the heater hose with the all-thread and hose clamped it together. So, basically the all-thread only keeps the plug in the water pump. When I started the car back up, no leaks! I let it get up to temp and shut it off because I had to go. It sounds a lot better and I believe it will be ready to go to the new home soon.

I believe it was mentioned here, but just go ahead and tap that nipple for 1/8" NPT and put a real pipe plug in it. Then use the dorman cap just for the aesthetics of a finished edge. I ran that on my 318 for at least 7 years.

There is no nipple on the manifold for a return that I can see. There is just that boss where an AC compressor would mount. My M1 intake has that extra nipple where I could feed it back to the manifold.

https://www.forabodiesonly.com/mopar/threads/edelbrock-ld4b-layout.327353/

I'm talking about tapping the ID of the water pump heater hose nipple to 1/8" NPT. The one you put a rubber cork and all-thread on.

Yep, now I understand. I just need to get some NPT taps.

Just remember NPT threads are just that, tapered. If you tap too far, you stand the chance of the plug not getting tight anymore. Sneak up on the depth you tap it and don't go crazy on torque, the cast aluminum won't like that. A dab of RTV or some teflon tape, snug it up and go.

For what it's worth I tapped mine with the pump on the car. Shavings were minimal, I flushed out the pump the best I could with the lower radiator hose off and went on my way. Pump never did give me a problem.

Even though it's aluminum, I would recommend oiling the tap when cutting the threads. Just seems to work better.

Well I thought that I would take your advice and do just this. The problem is that I pulled out an old water pump to do a test fit with the 1/8" NPT tap. It drops right in.

Did you mean to use a 1/4" NPT tap?

Well I’m certainly glad that I found this thread. My Dorman rubber cap would have failed as well.
Here’s a shot of a quickie tap on an old water pump. It’s a 1/4” tap and now I'll have to do this on both of our cars.

Thanks

Mine was actually an 1/8" NPT, perhaps just a different casting aftermarket pump than what you have.

I've come to a hard decision, but I'm posting the car for sale. It's in the Classifieds section.

Samy, sorry to see you have the car for sale. But in the bigger picture of life, cars are just cars. I totally understand where you're coming from though, good luck with the sale!

Thank you, sir. I've gotten quite the backlash since the car has been posted for sale 12 hours ago. The car is just a car and at the moment, there are just other things I want to focus on right now.