>.... My brother is into cooling systems and used an electronic
>temperature gauge with a needle-like sensor on mine. ....
Scott,
Michael brings up some interesting points. You can buy a "AC" thermometer
at most auto parts store. About a 3/4" round face with a long stem coming
out the back. Stick it in your center air vents and turn on the AC and drive
around. See what the lowest temp reading is. It should be down about between
35-40 deg F. This is measuring how cold the AC unit can get the air.
If not, then there could be a couple of problems even though your system is
"fully charged":
1. You hot water control valve is leaking and letting hot water into the
heater box. The hot air is blowing across the AC coil and heating up
the air.
2. There is some sort of expansion valve in the line, that could be messed
up or cloged. This will reduce the efficiency of the AC system.
3. There is temp switch on the side of the cooling coils in the AC box. It
has a long tube that goes into the cooling coils. If that switch isn't
working properly, the unit can freeze up (also if you don't have enough
refrigerant in the system).
Do you know if the unit is freezing up?
I don't know what it will cost to have the AC system really checked out.
I found a fellow (through the local chapter of the Antique Automobile Club
of America - AACA) that is a retired AC fellow. He now works on peoples
car in his spare time. Very cost effective!!!
If we have established that your AC is making COLD air, there are some more
possibilities:
1. How long are you driving the car. I keep the AC thermometer in the vents
on 1 of my street cars all the time. As I said in a earlier post I only
live 10 minutes from work. When I leave work on a hot summer day, the
car doesn't start to really cool off until I'm within a few blocks from
home. This is due to the short drive, and the large amount of heat that
has been accumulating in the car all day.
So maybe you're problem is the same. Take it out for a drive of at least
1/2 hr or more. Put one of the AC thermometers in the vents and one in
the seat next to you. See what the interior temp is.
2. Are you doors in the heater and AC box working correctly? Do you want
cold air comming out on the floor or only the vents? Is it doing it
correctly?
I do think that relocating the AC box to get a better alignment with the
heater box is a big help. (Although I really can't speak from experience
only theory.) If relocated my box, but don't have the AC working yet. We
have had to pull the AC box out and replace the 2 lines - they were both
cracked and leaking from age.
We did however do this to Jim Kelliher's car. Seems to have made a big
difference. We also had my AC friend charge Jims car just before he left
for the Meet last July. He said that it blew cold the entire trip and he
was nice and cool. If you do decide to move the AC box, do it on a cool
day, and try to get at least 1 helper. Makes the job a lot easier.
Finally, how often do you drive the car, or should I say how much does it
sit. I don't know what happens when the "seals" dry out - does the system
leak down, or do the internal seals shrink and then the system can not
perform up to part? I do know that NOT using the AC a lot, will let it
leak down more than if you use it. I use the AC in my 84 Accord almost
9 mo. out of a year, and when not in full time use in the winter, I still
try to run it at least every couple of days. The car had the original
charge on it until this summer. The compressor is going and somehow
dropped the charge when the car wasn't driven for about 15 days.
Hope this helps. Keep us informed on what you find out?
John
John T. Blair WA4OHZ email: jblair@exis.net
Va. Beach, Va Phone: (757) 495-8229
48 TR1800 48 #4 Midget 65 Morgan 4/4 Series V
75 Bricklin SV1 77 Spitfire 71 Saab Sonett III
65 Rambler Classic
Morgan: www.team.net/www/morgan
Bricklin: www.bricklin.org
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