Hi guys,
I bought this beauty a year ago and at that time the AC system was flat. I replaced a line that had a huge hole in it, pulled a vacuum, charged it with R12 and it started making cold air !!!! Oh happy days !!!
AC runs great until I take the transmission out of Park (and put it into Drive or Reverse). At that point it just fan shuts down. If I put it back in Park the fan starts blowing cold air again.
What the heck ? My only thought is that it might have something to do with the neutral safety switch (it hisses when I put car in Drive).
Any suggestions ??
Page 13-20 or 13-22 of the 1964 shop manual (I don't remember which) has a vacuum circuit diagram which shows that the vacuum input to the neutral switch is interconnected with the vacuum input to the dash control head for the climate control. I would suggest a review of that diagram, and checking all fittings for leaks. The hissing of the NSS could also indicate an improper adjustment. Does the car start only in P and N, and not in any other range? Do the reverse lights turn on in reverse, and not in any other range? The shop manual provides some instructions on how to adjust it.
-Charles
If it hisses that bad and the hoses are not disconnected, the switch is bad. It's creating enough of a vacuum leak to disable the climate control (I believe the steamboat switch needs vacuum to turn on the fan). All that controls at the switch is the automatic parking brake release anyway. Disconnect the supply line at the switch, plug it (golf tees are great for this) and see if that works. If so, leave it plugged until you get another switch (if you want to use the automatic parking brake release).