Hi... The defroster/blower for my '63 C10 is not working. I keep blowing fuses immediately when I put a new one in and turn on the blower. What would cause this and what should I be looking for? Thanks!
It sounds like it might be a short in the power wire running from the switch to the motor, or a short in the motor windings. An easy way to determine which, would be to run a separate wire (with an inline fuse) and connect it directly to the motor from a power source. If the fuse blows the motor is the problem. If it doesn't, the problem is elsewhere. If the motor worked on high speed but not mid or low speed, I would think it's the resistor. You might want to pull and inspect the resistor anyway just to look and make sure it isn't physically damaged. It's on the back of the ducting inside the cab and just snaps in and out.
I use to keep a spare resistor in the glovebox ,especially during cold weather. My '66 was famous for burning those out. Glad you found out what it was.
