Leak in Dash Heat/AC control

[michael g. linderman]

Thom

I have recently purchased pieces from Dale.

Arch has too... Dale made a delivery to see Arch.

Keep trying to reach him.

It took me a few calls to get to him, but when I did he was enjoyable to
talk to and had a few items at a good price

Mike Linderman
76 Eleganza II
Ft Wayne, Indiana

 

[thom hole]

I have introduced a vacuum leak in my dash heater/AC control switch when I
reworked the dash. The control 'disc' That has all of the vacuum lines
attached appears to be OK. In fact, the system works great when the engine
is at idle with high vacuum. The problem appears when you 3-5 minutes at
cruise with the vacuum lower. At that time the system reverts to the
'Vent' setting even though the switch is set to something else (heat,
Defrost). As soon as you get off the gas (and restore the higher vacuum)
the different valves open/close to reflect the setting of the switch. Any
thoughts out there?? Could this be a broken or split vacuum hose going to
one of the valves?? Hoe do you diagnose such a thing??

As a part of pursuing this issue, I have tried to call Dale Anderson
(815-485-2462), who is supposed to be 'parting out' a couple of GMCs to see
if I could buy a used replacement. There's no person answering, just a
machine, left message. Any other potential source for a replacement
Heat/AC dash switch??