Thermostat?
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Yeah, it's factory I believe
Laughing Gas
Joined: Nov 2013
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From: S.E. Louisiana;so far USA
I have a 1973 f-100 with a 302 and factory air (I think). It now seems to run a lot cooler but it never gets to operating temperature. It used to go about 5/8-3/4 of the way up the gauge with the old radiator, but still stayed well within normal range. Now the needle barely moves. At first I just thought my gauge was inaccurate, but now it's getting colder and my heat isn't really working that well, so I'm thinking thermostat.
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The heater function may be a separate issue from the operating temperature of the engine. As mentioned, things like an air door or heater water control valve could be the problem for the heater. As far as the engine's operating temperature goes, perhaps using a known good thermometer would be an accurate indicator. It's hard to imagine that the engine will not warm up if the thermostat is closed, unless you live in a really cold place.
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I'll try that, the new thermostat worked and it now gets up to normal temp. I'll check the heater hoses when I get home in a bit, thank you all for your help
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Tried the hose test, they are not hot. Room temperature air coming from the vents
ill look into replacing the core and go from there, thanks guys!
ill look into replacing the core and go from there, thanks guys!
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Laughing Gas
Joined: Nov 2013
Posts: 1,207
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From: S.E. Louisiana;so far USA
Could also be a problem with heater coolant valve, air door, or control.
Post Fiend
Joined: Apr 2002
Posts: 19,311
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From: Waterloo, Iowa
I'd try unblocking the stoppage before tackling a heater core replacement, depending on the rig it can be a &%#ing Pain dè Royale.
Try backflushing with a garden hose or shop air, something like that, if you have it.
Try backflushing with a garden hose or shop air, something like that, if you have it.
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I'm going to flush the lines and check all of that just in case. I don't want to replace that core if I don't have to
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that's what I'm going to do, maybe that's the problem. First I'm going to take the hoses off and flush them, then try and flush out the core somehow, if that's possible
Post Fiend
Joined: Apr 2002
Posts: 19,311
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From: Waterloo, Iowa
The hoses are probably clear? Try to determine the inlet and outlet hose. Backflush or, direct a strong stream of water in the opposite direction of normal flow. Think heater hose is 5/8"? Maybe a female garden hose end could be temporarily installed. Betcha a bunch of crud gets dislodged. Even if that's not the problem, it probably needs it anyway.
Ford Parts Specialist
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From: Simi Valley, CA
D4AZ-18495-A (replaced C7SZ-18495-A & D1AZ-18495-B) .. Vacuum Controlled Heater Water Valve (Motorcraft YG-136) / Available from Ford
1973/79 F100/350 & 1978/79 Bronco with factory installed integral A/C // With factory A/C: 1967/76 Thunderbird; 1969/73 Mustang/Cougar; 1969/78 Galaxie/LTD.
1972/76 Torino/Ranchero; 1974/78 Pinto/Bobcat; 1975/91 Econoline.
1973/79 F100/350 & 1978/79 Bronco with factory installed integral A/C // With factory A/C: 1967/76 Thunderbird; 1969/73 Mustang/Cougar; 1969/78 Galaxie/LTD.
1972/76 Torino/Ranchero; 1974/78 Pinto/Bobcat; 1975/91 Econoline.