Greg:
Your noise sounds suspiciously like a belt tightness problem to me.
Particullarly if you notice it every time the compressor clutch cycles on.
Most likely, high head pressure in the compressor causes sufficient
resistance duting each start-up cycle.
If I remember correctly, my system does not have the orifice tube (it's
actually a very small diameter conical screen inserted inside the tubing)you
mention. I believe it usually goes in the fitting attaching to the outlet
side of the dryer.
What was your source and part number for the dryer you purchased??
As far as your trip is concerned, you may be better off heading for home and
run the generator so you can then run the rooftop A/C unit. Doing that vs.
the loss in both mileage and engine power running the engine driven A/C
compressor, are reportedly about break even. That way you could have
someone at home you trust fix it and not be at the mercy of the unknown's
while you're on the road.
Paul
From: GONEMAD5
Sent: 7/3/99 9:49 PM
Subject: GMC: dash AC compressor nightmare (long-winded)....
Help! When i bought my GMC back in October, i knew that the dash AC had
not
been operational for a while, and the compressor was diagnosed as the
problem... So, about a month ago I had a rebuilt NAPA compressor put
in,
charged with R12 and everything was COOL... for about 200 miles until i
heard a squeal sometimes when the AC was on, going over bumps... I
thought
it was the belt, but later found out that the clutch on the compressor
had
gone bad. Of course, now i was 2,500 miles from the shop that had done
the
job for me, but at least the NAPA compressor was guaranteed. So, i
found a
local shop that could do the swap and R12 evac/recharge for me, went to
get
another NAPA rebuild, as well as an evaporator/dryer (which i was now
told
after-the-fact should have been done the first time). So now once
again,
everything worked fine until about 200 miles later ....i'm hearing the
beginnings of the squeal of death. In the midst of a holiday weekend
i'm
unable to get anything happening until Tuesday, but i have a few obvious
questions:
1) what could be the cause? (too much of a coincidence to blame the NAPA
part)? i'm now told after-the-fact (part 3), that you're also supposed
to
change the orifice tube when changing a compressor. Is this common
practice?
if so, then why didn't either of my 2 AC service shops advise me of
this?
any chance i could find this part local without having to special order?
Also told that perhaps the oil wasn't refilled to the proper level, or
perhaps too much freon was added, which would result in too much
pressure for
the compressor.
2) Is the compressor clutch perhaps able to be saved this time since i
caught
the squeal early and stopped using the AC?
3) I'm guessing that it must be the oil level that's the culprit. i
imagine
that when my old original compressor was taken out, the oil level could
have
been very low, and the mechanic just took a wild guess at how much to
add
(?). then, the 2nd mechanic just copied the previous level. What's the
rule
of thumb here?
(4) I was able to locate and pick-up a 4 Season's compressor right
before all
the shops closed on Saturday, and in case this last NAPA compressor is
fried,
does anybody have anything good or bad to say about 4 Season's?
Thanks in advance for any advice! I was supposed to leave 4 days ago,
heading back from Boston to LA... Don't want to even consider this long
solo
drive w/o dash AC!
regards,
Greg
78 Eleganza II
Your noise sounds suspiciously like a belt tightness problem to me.
Particullarly if you notice it every time the compressor clutch cycles on.
Most likely, high head pressure in the compressor causes sufficient
resistance duting each start-up cycle.
If I remember correctly, my system does not have the orifice tube (it's
actually a very small diameter conical screen inserted inside the tubing)you
mention. I believe it usually goes in the fitting attaching to the outlet
side of the dryer.
What was your source and part number for the dryer you purchased??
As far as your trip is concerned, you may be better off heading for home and
run the generator so you can then run the rooftop A/C unit. Doing that vs.
the loss in both mileage and engine power running the engine driven A/C
compressor, are reportedly about break even. That way you could have
someone at home you trust fix it and not be at the mercy of the unknown's
while you're on the road.
Paul
From: GONEMAD5
Sent: 7/3/99 9:49 PM
Subject: GMC: dash AC compressor nightmare (long-winded)....
Help! When i bought my GMC back in October, i knew that the dash AC had
not
been operational for a while, and the compressor was diagnosed as the
problem... So, about a month ago I had a rebuilt NAPA compressor put
in,
charged with R12 and everything was COOL... for about 200 miles until i
heard a squeal sometimes when the AC was on, going over bumps... I
thought
it was the belt, but later found out that the clutch on the compressor
had
gone bad. Of course, now i was 2,500 miles from the shop that had done
the
job for me, but at least the NAPA compressor was guaranteed. So, i
found a
local shop that could do the swap and R12 evac/recharge for me, went to
get
another NAPA rebuild, as well as an evaporator/dryer (which i was now
told
after-the-fact should have been done the first time). So now once
again,
everything worked fine until about 200 miles later ....i'm hearing the
beginnings of the squeal of death. In the midst of a holiday weekend
i'm
unable to get anything happening until Tuesday, but i have a few obvious
questions:
1) what could be the cause? (too much of a coincidence to blame the NAPA
part)? i'm now told after-the-fact (part 3), that you're also supposed
to
change the orifice tube when changing a compressor. Is this common
practice?
if so, then why didn't either of my 2 AC service shops advise me of
this?
any chance i could find this part local without having to special order?
Also told that perhaps the oil wasn't refilled to the proper level, or
perhaps too much freon was added, which would result in too much
pressure for
the compressor.
2) Is the compressor clutch perhaps able to be saved this time since i
caught
the squeal early and stopped using the AC?
3) I'm guessing that it must be the oil level that's the culprit. i
imagine
that when my old original compressor was taken out, the oil level could
have
been very low, and the mechanic just took a wild guess at how much to
add
(?). then, the 2nd mechanic just copied the previous level. What's the
rule
of thumb here?
(4) I was able to locate and pick-up a 4 Season's compressor right
before all
the shops closed on Saturday, and in case this last NAPA compressor is
fried,
does anybody have anything good or bad to say about 4 Season's?
Thanks in advance for any advice! I was supposed to leave 4 days ago,
heading back from Boston to LA... Don't want to even consider this long
solo
drive w/o dash AC!
regards,
Greg
78 Eleganza II
But this brings up an interesting point that i
