It seems like there are two types of heaters on old trucks-those that work really well, and those that don't work at all. Why there isn't much of a middle ground I don't know; it's one of the many wonders of the world.
Well, it's wintertime again, and while we Southern Californians may not have the frigid winters that torment the rest of the country, we get covered in a cold damp blanket in the mornings, affectionately known as the marine layer. I've been trying to work out the gremlins in my '72 C-10 so I can get it to daily driver status, one that both myself and passengers could be comfortable in, but the heater was leaving me out in the cold. Enough was enough; it doesn't work now, so what was the harm in trying to fix it? While I had never attempted to decipher all the levers and cables running to and fro under the dash of any of my vehicles, I didn't think I could make it much worse.
I knew I was going to need some new parts to make this happen, so I flipped through the back of CLASSIC TRUCKS and looked for a company who could help. I settled on Harmon's Classic Chevrolet and logged onto www.harmons.com to peruse their wares. Under their heater section, I found a new heater core, a heater control rebuild kit I needed badly, a heater-to-firewall seal kit, and ducts and vents, too. Since this was uncharted territory for me, I also ordered the '67-72 Chevy/GMC Factory Assembly Manual, which is good to have for any situation or educational bathroom reading.
Aside from the parts I ordered from Harmon's, I also picked up some semi-gloss black rattlecans to repaint the heater boxes while they were out, which were filthy inside, by the way! You'll be happy you did this when you see how much dirt is in your heating system. The instructions also call for some Krylon #1403 Dull Aluminum spray paint if you have the silver or chrome-faced controls, like mine; if you have the black face, use Krylon #1613 Semi-Flat Black. I also picked up some 3M weatherstrip adhesive and 3M Strip-Calk, which is a sticky non-hardening weatherstrip; there are a couple of different types out there, but something comparable will do. Other than that, follow along for the details, and pretty soon you can keep nice and toasty this winter for less than a new winter wardrobe!
Harmon's Classic Chevrolet has the goods to rehab your Chevy's heating system. Here we hav
Here's part of the cold-air culprit-the old heater control assembly. It worked as well as