REBUILDING YOUR HEATER CONTROL VALVE
FORD 1953 TO 1963
BY STEVE CLINE
More often than not, the leaking part on a heater control valve is a rubber diaphragm that is slightly bigger in diameter than a quarter, or a seal between the heater control valve and the heater core. If the cooling system has always been maintained with a mixture of 50% water and 50% antifreeze, the metal portion of the heater control valve will most likely be usable and only require some light cleaning with “brake clean” soap and water. Take the complete unit (heater core and heater control valve) to a quality radiator shop and have it tested for leaks so you can repair the complete unit and won't have additional trouble a hundred miles down the road.
Replacement diaphragms are available from
Rebuilding a heater control valve:
1) Clean valve with 'brake clean" and hot soapy water.
2) Check the water tubing on the valve to make sure that the metal has not rotted.
3) Disassemble the moving parts from the heater valve, making sure that you remember how they go back together. Be organized and take notes.
4) On my unit there are 4 flanges that must be bent upwards. Take your time, this is the hardest part.
5) Remove the water tube and you will see the rubber diaphragm to be replaced.
6) Check the seat for the water shut off plunger to make sure that it seats well, as it may need cleaning inside from an accumulation of 44+ years of crud.
7) Assemble diaphragm onto plunger stem and insert flanges onto body of the heater control valve.
8) Bend flanges down.
9) Re-assemble working mechanism of the heater control valve.
10) Mount heater control valve onto heater core with a new seal.
11) Take the completed unit to your quality radiator shop for testing.
Additional models of cars that this diaphragm will fit: AMC 1955.73, Chrysler 1950-69, Desoto 1950-63, Fiat some early models, GM 1950-63, Hudson 1950-55, HICK 1950-75, Packard 1953-55, SAAB1974-80, Studebaker 1950-63, Volvo through 1983.