VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Heater & Defroster knobs

In 39 Master Deluxe I have two knobs. One that controls the Heater and one that control the Defrosters and are mounted on the underside of the dash. They both work by rotating them. Each also have a bulb in the middle of the knob. An the moment I can not get them to turn off. Can these be rebuilt. Or is there some place to get replacements

I have no experience rebuilding them but, if it were me, I'd pull them for inspection and a good cleaning & go from there.

Hello Twigs ....
Yes, the controls can be cleaned / refurbished. My son cleaned both of mine for my '37 MD. They had dead spots and now they work much better. Also, when you remove the knobs from the switch portion make note of the position. If I remember correctly the knob & the switch are (kinda sorta) keyed. When working properly the light bulb should shine brighter for the higher speeds.
I did do some searching and could not find a vendor for any kind of replacement parts ... perhaps someone knows of a parts vendor.
good luck ....

rgds jim p

.... If your woman can't find you handsome .... maybe she can find you handy ..

Thanks Jim...I see you can take the switch apart with some clips being moved. How did your son clean it? Did he take the switch apart?

Twigs ...
I'll be with my son tomorrow ... I'll ask which cleaning fluids he used, etc. I'll get with you in the next couple days.
Send me your email address via the PM. I have a photo that might help you.
rgds jim p

Great..I will ..Thanks a bunch...

Jim
Did you get my email address?..My switch looks like this.

Hello Twigs ...

Two links are included to provide info on two of the products used. My son had these products readily available.

The aerosol spray is the deoxit compound diluted into solvent that is good for flushing out dirt and corrosion. For actually removing the oxidation the concentrate is much more effective. Tough jobs can benefit from having both... but if one already has a good spray solvent... probably fine just to use that for cleaning and only purchase the D100L concentrate.

Some isopropyl alcohol and acetone might also have been used during the cleaning … that my son does not remember.

His tools included a plastic bristle brush, brass bristle brush, fine-point cotton swabs … and likely some 600 grit sandpaper for the wiper and any other surfaces that needed to be sanded.

https://www.amazon.com/DeOxit-Cleaning-Solution-Spray-spray/dp/B0002BBV4G

https://www.amazon.com/CAIG-LABORATORIES-D100L-25C-Contact-Cleaner/dp/B0000YH6F8

I would add the 'after the clean-up' photo; however, I don't have the rights to add a file.

Your switch looks very similar to mine, if not exactly like mine.
good luck with the cleaning .. let me know the results.
rgds jim p