I admire your bravery, Bill! 6 volt GMC gauges with a 12 volt supply. I got some kind of reducer(?) and put that on the incoming side. (I’ll check to make sure I picked the right side and get back to you.) Original was positive ground, of course, so there’s that added ? In the mix. Maybe I need to start a new thread instead of high jacking this one.
Thanks, Nate. I’ll be on the lookout. It would be great if the original was still willing. I drive my truck a lot, and once I get the door glass in it, I’ll drive it just as much in the winter, as long as the heater works- especially the defroster.
Yes, the original motors are pretty stout . It's a seriously fiddly job to open them up and replace the brushes but IMO well worth the effort . Grainger sells a nifty 12 drop in replacement fan motor, no I don't remember the P/N although there's an unused one under the piles 'O crap on my dining room table . My old Mercedes HVAC motors always need brushes, Ma Benx used to get $1,200.00 for them , I bought one aftermarket one and didn't like it, took it back out and gave it to a buddy up near the Canadian Border who lives off the grid, he loves having robust heat in his old 240D again, I taught my self how to take the original BOSCH motors apart, clean out the accumulated dust and crud, replace the soldered in brushes ($10/ pair) , re lube and so on, I have two waiting to be installed right now , always things to do . FWIW, the electric motors and fuel gauges care not a whit about polarity, just the VOLTAGE ~ DO NOT use one of those ceramic dropping resistors ! . Go to 5th Avenue Auto Parts and buy the proper one from Randy or cobble one up using Radio Shack voltage regulators .
