|
Sunday, October 30, 2005 - I spent a few hours
this afternoon getting some parts boxed up for shipment, and
then decided to kill a little time getting acquainted with the
factory underdash A/C setup, since this is what I'll be using
for my project truck. I have three units, two of which had
cracked cases and therefore would be my parts units and a third
with very minor case damage that I would repair and use.
First of all, I was kinda surprised to discover that the three
factory A/C units I have were all a little different. Even
though I've had them all for some time, I'd never really paid
that close attention to them. In
case you weren't already aware, '68 was the first year for the
large suitcase-type factory A/C unit. The '68-'69 units' front
aluminum trim panel was black with silver horizontal ribs, which
was replaced with a flat woodgrain panel for the '70-'72 trucks.
The front register vents are also styled differently....except
on the '70 model. It appears that '70 was a transition year, in
that the A/C units used the earlier-style register vents but got
the new front woodgrain trim panel.
Since I figured I'd probably break something during disassembly,
mainly due to my inexperience with them, I grabbed the unit with
the worst case damage and set it up on the workbench for
disassembly, which was the '68 unit (Fig. 2). The first order of
business was to get the front case cover off. After removing
about a half-dozen screws, it became apparent that unless I kept
track of where each screw was removed, I'd have a heck of a time
during reassembly....so I came up with a neat idea. I cut out a
chunk of cardboard app. 12" x 16", drew a rough sketch of the
A/C unit on it, and then placed each screw into the approximate
location on the sketch (Fig. 3). This will help immensely during
the reassembly process.
After removing the front case cover (Fig. 4), I got my first glimpse of
the inside....and man, it wasn't pretty. Since this unit had
come from a non-operational parts truck that had been sitting
for a while and had become a home for field mice, there was some
nasty-smelling debris inside that I could see would need to be
cleaned out once I got into it a little more.
Next
on the list was to remove the A/C evaporator. It's simply
screwed down with 4 sheetmetal screws (Fig. 5). Then I removed
several more screws to remove the metal plate that the blower
motor is secured to, and set it out of the way.
The
metal plate underneath the condenser is what needs to be removed
next, to get access to the heater core (Fig. 6). The core is
retained by four sheetmetal screws.
At
this point the A/C unit is almost completely disassembled and
ready to be cleaned up. I'll be adding another page in the near
future showing the cleanup and assembly process. Since I have
two other units, I'll be combining the three into one good
useable unit. Stay tuned!
|
Fig.
1 - This shot shows the differences in the front trim panel and
the front registers.
Fig. 2 - The '68 unit became the guinea pig for disassembly,
since the front grille area had several fins broken out and
missing.
Fig. 3 - Here's a view of the 'bolt board' I made to keep track
of the screws I removed during the A/C's disassembly. This was
taken right after the front cover was removed.
Fig. 4 - Here's a view of the suitcase with the front
cover peeled back.
Fig. 5 - The evaporator has been removed, revealing the
metal plate underneath, hiding the heater core. |
