Plugging or Capping Water Inlets/Outlets

Ron Earp

Admin
The new V6 I'm building for the Mustang has a number of water pump lines that need to be capped. Little short tubes like shown on the upper left of this pump:

M8501C50.jpg


In the past I've cut them off, plugged them with a metal plug, or, used a piece of heater hose with a pipe plug clamped in the end of it. Both solutions worked well.

But I don't want to cut the fittings off this time and I'd rather not redneck plug them with heater hose and a pipe plug. I might want to use the fittings for a the heater core later. Does anyone have any suggestions for an elegant solution here that would be reversible?

I found these at McMaster:

McMaster-Carr

But I'm not sure they can handle being clamped or what pressure the water system develops (< 15 psi I'm sure).
 
I assume these are heater core lines, Ron. If so, why not just run a short length of heater hose looped from one to the other, simulating the heater core you say you may want to add later?

Easy to do, cheap and probably pretty reliable.

If I were really racing this car, I'd pull the tubes out, tap the holes and close them with pipe plugs or AN fittings/hoses that looped around like the heater hose suggestion above, mostly for the presumed safety factor with AN fittings and hose as opposed to heater hose and worm clamps.
 
Ron,

If the tubes are thick enough and the right size you may try threading them and then put a plug in or thread the outside and put a cap on ... still usable in the future but water tight under pressure... just a thought richard
 
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Hi Ron I took a look around the Garage just now and couldn't find the bag of these ( can't remember if I picked them up at Jeg's or Summit ) But here they are on line Heater Hose Delete Cap I have also seen them at swap meets. Wally
 
Notice how similar this is to your old 302 pump, you need the T-Stat bypass.

To remove the heater return grab an old hacksaw blade & sp;lit the ID of that heater return fitting so you can yank it out like a loose tooth..

Wonder if it has a pressed steel impellor, do I get a sense of history about to repeat itself here.:)
 
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Ron, I just soldered a dime over the tops of these a few years back. The solder will hold the pressure just fine and when you want to add a heater you just get out the butane torch and off they come. Simple and elegant.
 

Ron Earp

Admin
Notice how similar this is to your old 302 pump, you need the T-Stat bypass.

To remove the heater return grab an old hacksaw blade & sp;lit the ID of that heater return fitting so you can yank it out like a loose tooth..

Wonder if it has a pressed steel impellor, do I get a sense of history about to repeat itself here.:)

Thanks for the ideas guys.

The picture I put up is a 302 pump, the V6 is similar but only has one water return that is teed and three from the manifold.

And Jac Mac, I'm slow but learning - Stewart has two of the V6 pumps in hand now to build me a race pump. The V6 pump looks just like the crappy V8 pump that failed the Lola. We don't want to see that movie again!
 
Dear Ron

use it as main feed connection to and from your expansion tank. It is on the low pressure side of the pump. It helps to maintain a higher pressure in the incoming side of the pump, thus minimizing cavitation likeliness. Basicly works as good as a T in the main return line from the cooler just in front of the pump intake.

See my other post about WP theory.

TOM
 

Ron Earp

Admin
Dear Ron

use it as main feed connection to and from your expansion tank. It is on the low pressure side of the pump. It helps to maintain a higher pressure in the incoming side of the pump, thus minimizing cavitation likeliness. Basicly works as good as a T in the main return line from the cooler just in front of the pump intake.

See my other post about WP theory.

TOM

Good post on the water pump theory. I believe you have explained that situation fairly accurately.
 

Terry Oxandale

Skinny Man
The plugs or caps you originally described from McMaster would not work. I've used much smaller ones, exposed to the same pressure, and the combination of heat and pressure resulted in a failure. I was only experimenting, but chose the short hose stub, with aluminum rod (it was actually a 3/4" or 7/8" aluminum bolt shank with the head/threads removed, squared off, and filed smooth) cut to a reasonable length (3/4" in my case), and then clamped into the hose with a hose clamp. In my mind, it looked more sanitary than the Summit part, which I've used before as well. The Summit part eventually swells a little bit and just didn't look as well once clamped in place as the rod-in-hose method.
 

Randy V

Moderator-Admin
Staff member
Admin
Lifetime Supporter
Hi Ron,

I just lay the WP flat on my bench and clamp a vice grip on the thin pipes and twist them as I pull on the vice grip and the come right out. The holes left behind are just about perfect for 3/8 and 1/2 NPT taps, then I screw in brass plugs..

Maybe hard to see here and will look for better pictures when I get to a real computer rather than this iPad..

IMG_1325.jpg
 
napa auto parts sells caps in both sizes. They look like rubber cups. Just put over the tube and put a hose clamp. Looks professional. If i had the pump off the car i would tap it and put brass plugs in it. No worries about the rubber cap rotting.
LLoyd
 
Ron-
I just used a straight tap with a pitch diameter a little larger than the cast aluminum tube to thread the ID, coated a SS cap screw with high temp thread lock, and screwed it in tight. Reversible and looks sanitary.
 
As Will Campbell says, the easyist way is to connect the 2 tubes. I have done this on my '40 after one of the previously installed plugs (not installed by me) blew out and dumped a lot of the coolant. No problems since. It only needs a short "U" hose.

Hope this helps.

Chris
 
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