Defroster circuit closing

[Michel]

I took the truck for a short journey on Saturday morning and after few kilometers found that the temperature was increasing in the cabin even I was driving with windows opened. I check the defroster and found it hot as there are no valve to close the coolant circuit.
I plan now to install a valve/tap in order to close the circuit but don't know on which hose to install it:
The one coming from the water pump or the one on the thermostat housing?
Is there no risk for the water pump to install a valve in the circuit.
Any idea ?

Thank you
Michel

[tmoble]

the hot water will come from the the thermostat housing or near it. the return from the heater goes to the water pump.

How's things in France? besides the recent mass murder by an Islamic terrorist? Hot days of summer?

Michel, I don't know what it's like buying hardware type stuff where you are, but I recommend to try to get one of the 1/4 turn ball valves rather than the junky ones they sell for automotive use.

[_Ogre]

either line will work, both line are pressurized by the cap
sometimes you can get issues with flow or air trapped in the system
two 2mm (1/8'') holes drilled in the thermostat will alleviate all issues
do keep an eye on the engine temps when you drive it a few miles

i've run many with valves, plugs and by pass hoses over the years with no problems

[tmoble]

What Ogre said.

[mr48chev]

+1 for what Ogre said. In or out it doesn't really matter as long as you cut the flow off.

A lot of guys use a control valve similar to this one that is operated by a cable

It fits 66/72 Ford Broncos and some Ford pickups along with some mopar pickups.


I'd think that you could find a similar valve in France that fits something made there though.

I had a truck a few years ago that came with a ball valve in the heater line that you had to open the hood to open or close the valve to the heater or adjust it to get the right amount of heat. Simple but not very convenient.

[tmoble]

Mr48, I've had that type and they rust and fall apart. Is it the part itself or the cruddy water here in Phx? This is why I started using the inconvenient ball valves.

[mr48chev]

I haven't had that problem but they do sell plastic ones that won't rust. I' thinking that some of them for Mopars that are quite similar in design are made of plastic. The ball valve actually works great but as we agree it is somewhat inconvenient. Here locally at certain times of the year we have 80+ days and the nights get down in the 30s so you might head out when it was nice and warm and be heading back when it is pretty chilly.
The truck I had that came with one was a 64 GMC that had a lot of "modifications" that were a bit questionable but I used the truck as a work truck on a dairy farm and it was great for that.

[Michel]

Thank you all for your advices. I will start searching for a valve, may be starting with a 1/4 ball one as it is easy to find here jusdt to stop being cooked each time I drive the truck. I have measured the hose and the diameter is 5/8" ID. Next step will be to find something with cable so I can actuate it from inside of the cab.

@tmoble : France is a quite country until those fu... guys starts to bother us, I think this is not the right place to discuss that here. Temps are now lowering with only 28°C during daytime now, we got 35°C last week, better to stay inside the house. No airconditioner in house or truck, nether at work, c'est la vie !

@_Ogre : Thank you for the advice of drilling holes in the thermostat, but on the body or 'valve' ?

Thank you
Michel

[_Ogre]

a regular ball valve works, a little bulky after screwing in 2 hose nipples
some of the mopar plastic valves have 4 ports: 2 in, 2 out
when in off position it bypasses in a closed loop
jeep valve,vac operated




1 or 2 small hole near the edge works, like this