Heater issue
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Joined: Nov 2018
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Heater issue
The heater in my '72 is acting weird. It is a Vintage Air unit my father installed (gen IV, I believe). If you start the car and let the motor warm up but not drive it, the heater will blow out hot air. Once you get moving though, it cools down and the air is just above ambient temperature.
I took some measurements with an infrared thermometer. If I let the car warm up in the driveway, the heater hoses are about 170 (my thermostat is 180). The hoses feel hot and firm like they have some pressure to them. This is when the heater blows hot.
Once I drive it around, however, it cools off. The readings on the same hoses are then about 110-120 on the hose coming from the intake manifold. This reading is near the firewall and is the same before and after the heater valve. The hose doesn't feel like it has the same pressure it did when it was hotter. Also the temperature near the intake manifold outlet is warmer, about 150. Thoughts? Is that a bad thermostat? The temp gauge reads about 180.
Thanks in advance,
Ivan
I took some measurements with an infrared thermometer. If I let the car warm up in the driveway, the heater hoses are about 170 (my thermostat is 180). The hoses feel hot and firm like they have some pressure to them. This is when the heater blows hot.
Once I drive it around, however, it cools off. The readings on the same hoses are then about 110-120 on the hose coming from the intake manifold. This reading is near the firewall and is the same before and after the heater valve. The hose doesn't feel like it has the same pressure it did when it was hotter. Also the temperature near the intake manifold outlet is warmer, about 150. Thoughts? Is that a bad thermostat? The temp gauge reads about 180.
Thanks in advance,
Ivan
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Joined: Sep 2004
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
a lot of us added ball valves to the heater hoses sometimes even on both sides to stop all hot water flow to the heater core to prevent this.
my guess is the the valve that controls the water flow to the heater core is failing and allowing water to flow to it all the time regardless of the heat setting
my guess is the the valve that controls the water flow to the heater core is failing and allowing water to flow to it all the time regardless of the heat setting
