58 GMC 1/2ton truck 6 cylinder. Have two outlets side by side on the firewall under the battery tray.Which one goes where? Thanks
From a technical view it doesn't matter you're just circulating the engine fluid through the heater core. Just connect them how they look the tidiest and you're good to go.
Ok, I ran the hose closest to the inner fender to the water pump.The other hose to the thermostst housing. Just wanted to know the correct way is all....
Truck (my '55 F100) was in my shop, engine out for cam change and other updates. Cleaned up the compartment, installed my new heater core in the interior housing, all restored nicely. Ran the heater hoses, connected everything up, ran in the cam, replaced the hood, got it out of the shop by noon Sunday, so I'd be ready for Monday morning rush! Omitted heater control valve, in my haste to get it done...That was ONE HOT SUMMER! Heater 'on' all the time... LOL Bad policy: "Hurry Up!" Always on my own stuff...never 'time'.
"Heater valve" Mine didn't have a heater control valve when I bought it?. So if I buy one where do I install it? Which line? from the water pump or the thermostat housing? I'm guessing waterpump
heater water valves were used on the "deluxe" heater, not on the "cheap" recirculating heater. If the heater has a single knob to control fan speed, and a lever to flip on the defrost, then it's the cheap heater. If it's the deluxe, it will have a control unit with 3 levers and cables, and a fan speed lever switch. Then the water valve is inside the housing, and is controlled by the TEMP lever and cable. The recirc heater does not need a water valve because air does not flow until you turn on the fan. The deluxe, air will flow without the fan on. If the heater core tubes are different sizes, the small one connects to the "hot" hose, which comes from the thermostat housing.
If there isn't a valve you can just put a valve from the hardware store in the line and shut it off in summer. Or get this one and connect it to a choke cable. They used the same valve for years and years on many Chrysler built cars and trucks. Try a 75 Dodge pickup if you go to your local parts store. http://www.ebay.ca/itm/HVAC-Heater-...ash=item36142971a3:g:l90AAOSw5cNYmN5N&vxp=mtr
I had a 56 buick Special and she had no heat when I brought her home.The heater on them were under the front seat.I remembering changing the T stat. and taking out the heater core and flushing it but still no heat. I though I wonder if the last owner had put the heater hoses on wrong? I changed them around and BANG! I had heat. I had to replace all the heaters hoses because they were so old. I think I had to buy about 20 feet of hose, but had good heat.LOL Bruce.
Just remember that the water control valve should always (ideally) be positioned to control or restrict the OUT flow of water from the engine before it heads to the heater core. If you accidently put the valve restriction between the heater and the return line to the engine, you will subject the heater core to higher burst pressures when the engine revs up. Picture the control valve as the dividing point between "high side" and "low side" pressures in the water flow. You may think that it doesn't matter, and that the 12lb or whatever radiator cap will keep the heater core from being overpressured, but internally you can generate quite a bit more internal surge pressure in between components when the engine revs up the pump output. If you connect the heater core outlet (pick one , heater cores can flow either direction) to the suction side (return line) of the water flow without a shutoff valve in the return line, and connect the inlet side of the heater to the control valve that is installed in the engine outlet or water outlet line, you will subject the heater core to much less line pressure surge in higher rev operation. It DOES make a difference especially to older heater cores that may or may not be built for the extra high coolant pressures of today. It DOES make a difference in pressure whether your heater core is on the low pressure (suction) side of the valve restriction, or the high pressure side (engine outlet or pump outlet) side of the heater control valve. Slightly different but related subject... I have seen control valves that are directional. usually the thermostatic type... The type that use a plunger inside the valve will sometimes be pressured to stay shut by the water flow if you hook them up the wrong direction with the flow from the engine pushing the plunger valve shut. If the water flow is such that helps push the plunger open, it flows and regulates correctly. You may think it sounds obvious, but it is easy to overlook it without realizing. why be ordinary?[/QUOTE]
Think about it. The hose coming out of the thermostat housing is the hottest water. The heater doesn't know or probably doesn't care. The return hose goes to the water pump just like the lower radiator hose. So the answer.... Make it look good. As for a shut off, I've seen them mounted under the battery in the feed hose. Kind of cheap looking thing with stem with about an 1/8" tee handle, they were br*** however...goodluck. It's fun reading about your truck.
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