Yep.  A common failure point in that vintage car is where the little
vacuum hoses attach to the vacuum resevoir (the big white container
that looks kinda like a weenie on the right side of the car.)  Typically
these hoses will split (always on the bottom where you can’t see ‘em)
and will allow enough vacuum to leak to make the heater inop.  Since
the system fails to air conditioning, that is what you get.  For minor
leaks, you’ll only notice the problem when accelerating or going up
hills.  (cold going up, hot comming down  Another common place is
where the vacuum is tapped from the intake manifold.

One reason the vacuum resevoir is such a common failure point is that
you almost always hit it with your arms while changing plugs or the
oil filter.  I’ll bet you just changed your oil, right?

IF you don’t find any problems in the above places, then inspect the whole
vacuum piping system for splits.  Especially check around the solonoids that
are mounted near the vacuum resevoir.  Also look under the dash on the
passenger side.  There is a damper and its associated hose within easy
reach of a passenger’s feet.

John

–
John De Armond, WD4OQC  | "The truly ignorant in our society are those people
Radiation Systems, Inc. | who would throw away the parts of the Constitution
Atlanta, Ga             | they find inconvienent."  -me   Defend the 2nd
{emory,uunet}!rsiatl!jgd| with the same fervor as you do the 1st.

manifold also-this can be a bitch or it can  be quite easy…
good luck-hope it is easy on your car.

–  

        Steve Kaess, Steve.Ka…@p0.f417.n109.z1.fidonet.org
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