Today, I ate a serving of elephant.
I decided to restore the heater assembly. I didn't take any before pictures, but I'm sure you can imagine what a 46 year old heater must have looked like. It lives way up under the dash and obviously never gets cleaned or even noticed as long as it continues to heat the cab.
First, a little theory. A heater is actually a very simple thing. The main component is a small radiator. There are two hoses that connect to this little radiator. One takes hot coolant in, that is, the antifreeze that runs through the trucks cooling system. The other returns the coolant back to the engine. As your engine runs, it produces heat, which is carried out to your radiator to be dissipated by the airflow, therby keeping the engine at a reasonable temperature. A heater core simply takes part of this coolant and runs it underneath your dash to a seperate small radiator. Using this little radiator and it's hot coolant, we can warm the inside of the cab by using a fan to blow air over it.
I started by disassembling the whole unit. Then, I bead blasted all the parts and powdercoated them in silver vein with clear. The smaller detail parts, I coated in gloss black. It's not a flashy choice of colors, but a heater is meant to be a utilitarian thing, not something to draw your eye's attention every time you sit in the truck.
Here are the main pieces after I took them out of the curing oven...
Next I got the list of new parts. I bought a new heater core, a new fan motor, a new resistor, and new sealing gaskets.
Heater core- This may seem overkill to some folks, but I have my reasons. If a heater core ruptures or begins to leak, that hot coolant I mentioned above now leaks into your floorboard. I tend to keep my feet in the floorboard area when I'm in the truck, so hot coolant sharing the same space with my feet is a bad thing. I wear Jerusalem cruisers (sandals) pretty often too, so 200 degree antifreeze running over my toes is not a good thing. Plus, the thing is 46 years old. It has to be corroded internally and running on borrowed time.
Fan motor- I sprung for a new fan motor too. The old one was hard to turn and I had my doubts whether it would turn quick enough to move a good quantity of air. Plus, old, gummed up motors pull excessive amperage from the electrical system, leading to blown fuses, burned out switch contacts and other issues. I figured why not spend the 30 bucks right now and never worry about it again in my lifetime.
Resistor- This is an inexpensive item, at around 11 dollars. The purpose of this is to vary the voltage going to the fan motor. By varying the voltage, you can control the speed of the motor, giving that wonderful feature we all love, hi-med-low, speeds to our heater. Money well spent.
Gasket and seal kit- This is a 13 dollar item that almost no one ever bothers to mess with. Here is why I did...The heater core is intended to be contained in a sealed box beneath the dash, with a fan blowing over it. When the old seals are damaged, shrunken with age, or just flat missing, the charge of air from the fan will leak out around the box seams, rather than be forced over the heater core and out the floor and defroster vents. Why go to all this trouble only to lose system efficiency because a measure of our blower air is leaking out in unintended places ?
The final tally for all of this was 125 dollars. That's pretty steep I suppose in the scheme of things. I had to order the parts from Missouri, so shipping charges are reflected in the above price too. I justify this expenditure to myself by the fact that with all of this love and care, this heater unit will perform exceptionally well for a long time. I figure if the original was still intact after 46 years, this should last even longer. The factory didn't bother with powdercoating the parts or fitting the seals as thoroughly as I did. Nor did they use stainless steel hardware for lifelong corrosion resistance. We can't have rusty screw and nuts now can we ?
The final product..