RE: [Chrysler300] heater 1964 300k

Cannot tell why / what is wrong --- only from a post, but generally the cardboard interlock cams inside the switch fall apart, need replacing. They are in grease it just makes paper based pieces fail. If you push one button , the last one pushed before that one, should come out almost all the way….if not , or some are hard to press , cam inside is falling apart. Being heavy cardboard , WD40 might make it fall apart more, but could reduce friction for now. . when interlock cam moves/slides sideways, that is what moves the vacuum switch, selecting canisters to act---not the push buttons directly. But seeing if buttons come back out tells you it is moving. New cams are engineering plastic (delrin) .

Vacuum leaks are another whole separate issue ; there is a lot of info on 300 site on that, and how this works, I believe? Canisters (the operating cans) can be checked with a mity vac . On both sides. Should hold vacuum. But check hose to engine , especially, often damaged while working on the engine .

If you unplug the vacuum hoses , at the switch, do NOT wiggle plug side to side trying to get it off, it breaks off the little nipples ; go straight back with plug when removing, might need help from small screwdrivers etc. take whole assembly out, then unplug carefully ? ? This from F -----I have never worked on K switch in the car.

Hope this helps

john

From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of Harry Torgeson torg66@xxxxxxxxx [Chrysler300]
Sent: Monday, December 18, 2017 3:14 PM
To: Chrysler 300 List
Subject: [Chrysler300] heater 1964 300k

Hi group, my mechanic sprayed WD40 into the heat defrost AC controls that were real stiff, now there easy to use but they do not work, should I rebuild the control or do I have a vacuum leak. Before the WD40 the controls hardly worked for AC, defrost, air flow.

Harry in Portland OR