70 Autotemp problems

["Peter Engel" <peter.engel@xxxxxxxxxxx>]

Having had a 70 LeBaron (for 20 years this month!) I can safely say that
I know the source of at least SOME of your cars problem.

The vacuum check valves located on the underside of the heater
core/evaporator case have failed.  When the valves won't hold vacuum,
the blower turn-on vacuum switch isn't activated.

These are plastic bodies valves with 4 ports each, p/n 2820 880.  They
are used on quite a few cars from the mid-60s up into the late 70s and
they all have the same problem -- an internal chamber cracks.  This is
because a plastic cap is pressed into the chamber and long term stress
causes the chamber to split.  Here's a pic:

http://www.bos-engel.com/imperial/theworks.jpg

I've used Parts Voice and other locating services to search for these
and they are out there.... At $20 -$40 each.  The problem is that I
believe ALL these valves will have the same problem regardless of
whether they're NOS valves sitting on a shelf or "used" parts in a
junkyard car.  I couldn't get any sellers to check the valves (simple
test with a short length of hose and a vacuum pump) so I didn't buy any.
$40 for a very likely broken, not returnable chunk of plastic was too
much of a gamble for me.

I've been searching for an alternative for the valves and even finding a
way to repair them using my lathe but that hasn't happened yet.

Pete in PA



From: IMP7T@xxxxxxx
Date: Sat, 17 Apr 2004 20:51:19 EDT
Subject: IML: Auto Climate Control

I have a 1970 Imperial with Automatic Climate Control.  Here is the
problem. 
The heater motor does not respond properly. If I activate the defrost,
it 
appears to work. When I switch to auto heat / cold the heater motor will
run at 
high speed. The AC works for several minutes and then quits. If I go
back to 
defrost, wait for the motor to start again, I can than go back to AC for
a short 
time. If I jumper the motor, all functions appear to be working. A test
light 
indicates that the motor in not getting any power. The manual states the

resister block might be bad. I cannot find this part. Any ideas? If I
find it, how 
do I test it.