67 Imperial Crown heater help

[weirdbeard]

Detmatt posted some pics of the differences. That probably explains it better than me.

 

[Ross Wooldridge]

I'm not sure. Sorry, but I need to go dark for a while and deal with Honey-do stuff. ;)

 

[weirdbeard]

Ha ha! Me too.

 

[detmatt]

And I have 2 non ac and one auto temp car here currently so I can’t even cheat for you. Although I might have a complete harness or 2...

 

[weirdbeard]

I may try ringing out the 3 terminal one with a tester and see what’s different.

 

[weirdbeard]

I was reading on the Imperial club website about these vacuum switches. It seems that the 3 terminal switch can replace the 2 terminal one by ignoring the extra terminal. This would definitely be cheaper since the original one is expensive if you can find it.

I tried the used one I have but it doesn’t work properly. Switch could be bad. On a/c the fan won’t shut off and in defrost or heat the fan will not run. I have to do some more investigating.

 

[detmatt]

I wonder if these are rebuildable?

 

[Ross Wooldridge]

Apparently they are. There's an article somewhere on line. I'll try and find it.

 

[weirdbeard]

There is a link on this site someone posted about rebuilding them yourself. I think it was from “A” bodies only.

 

[weirdbeard]

Ok I finally got around to the vacuum switch with the three terminals. I disassembled it and cleaned it up. I then installed it and it does in fact work in place of the two terminal original.
I just wanted to update so everyone has the info. Another item I just dissected and repaired was one of the vacuum actuators. The diaphragm had a tear so I siliconed it. I now have defrosters!

 

[Ross Wooldridge]

Here's that article for rebuilding these - although it's for an earlier model, the basic principles apply...

How To Rebuild a Vacuum Heater Control Switch