Trying to figure out the control of the heater. I heard they had a manual control valve - was there also one with a slider control on the dash? I only have two controls, FAN and DEF.
1. Where does the manual heater valve mount?
2. Can I add a slider-control to my dash and use the other valve, the one that operates with a cable?
3. How do you determine which heater core is correct? With "re-circulating air heater" or "fresh air heater"?
I suspect your heater and heater control is the same as pictured. 1st picture looks into cab, passenger side fire wall. Carefully observe the 3 cables running from the back of your panel to the heater box in picture. Heater core in 2nd picture - in upper left corner of heater core notice 1 of those 3 cables as it comes through firewall. Cables control louvers within heater box to divert air to DEF, AIR or Heat. 4th control level (you have 2 shown in your picture) is electrical switch to fan. Maybe orange wire. Pretty good chance your levers are broken off. Parts are easily available and rebuild is not hard.
Last edited by Hambone; 05/12/20204:41 PM.
~ HB 1966 Chevrolet K-10 | Ghost: formerly Flappy Fenders | In the Stovebolt Gallery 1962 Chevrolet C10 1962 Suburban
As said, your cable system needs rebuilt. Your whole heater system may need "rebuilt". All of the parts are available in the aftermarket. I rebuilt my deluxe heater and will use a remote valve positioned right outside the fire wall and operated by the lever and cable on the dash. Click and Click
May take a slight modification to outside box lid to fit new core.
Hi, Your pictures look very familiar. This is because I have the same year and design of heater in my 63 c10. Most 60-66 chevy/gmc trucks had 2 designs of heaters.
Deluxe: where the heater core and motor were in the engine compartment and the air box when in through the firewall into the cab. Most the these heaters had cores got pretty leaky, since they were on the outside of the truck. They also had more levers on the dash panel to control options of heat, hence they were "deluxe" in standards of the 60's.
Recirculating/Fresh Air: Is where the hole system is inside of the cab, under the dash behind the glove box. These systems had the heater core inside the cab, and usually a greater percentage of these that remained original had a good core last longer since they were inside the truck. The heater air box, core and motor are all in the cab underneath as well. They also only had 2 levers on the control on the dash. When working properly they work quite nice. I've had mine defrost the glass on cold days and heats the cab up in about 5 minutes while diving, since the cabs are not that big.
Reciculating heaters have a cable, so no need to buy another one. The defroster lever is hooked to a cable. When the defroster is "on" you will know this by being in the down position and their will be a flap on the heater box that closes and all the warm heat only rises up through the dash vents near the glass to defrost the glass. The heat is only on, and blows through the floor when the opposite is true. Up position and flap open. The fan simply operates the fan speeds: I believe there is 3 or 4 speeds.