AC - Bypass?
at1212b
04-03-2008, 01:55 AM
I was wondering is there some way to bypass the AC?
I know it may sound like a dumb question, but for my 87 Astro, many many years ago, I remember the AC didn't work, and when I took it to the mechanic for the general inspection, if I recall correctly they did something (maybe like a light switch?) to make it work again. I'm not sure how much they charged, but it wasn't that much.
Then it blew cold until...
one day, I had my engine bracket and bolt behind the power steering pump break. (the serpentine belt stayed on I think, but but wasn't moving properly/grinding against something)
As there was some kind of crazy whining/wheezing type noise which I was told that the AC compressor was broken causing that noise. As result they also tried to sell me a rebuilt AC compressor.
Is that possible? For the serpentine belt or break in engine bracket to cause the AC compressor to break?
Or is it possible that they turned 'off' the 'switch' in order to sell the AC compressor?
Its always been a mystery to me, and something that hasn't felt right (this happened almost 10 years ago now which I recall vividly) so if anybody has any input on it, it would be very much appreciated.
I know it may sound like a dumb question, but for my 87 Astro, many many years ago, I remember the AC didn't work, and when I took it to the mechanic for the general inspection, if I recall correctly they did something (maybe like a light switch?) to make it work again. I'm not sure how much they charged, but it wasn't that much.
Then it blew cold until...
one day, I had my engine bracket and bolt behind the power steering pump break. (the serpentine belt stayed on I think, but but wasn't moving properly/grinding against something)
As there was some kind of crazy whining/wheezing type noise which I was told that the AC compressor was broken causing that noise. As result they also tried to sell me a rebuilt AC compressor.
Is that possible? For the serpentine belt or break in engine bracket to cause the AC compressor to break?
Or is it possible that they turned 'off' the 'switch' in order to sell the AC compressor?
Its always been a mystery to me, and something that hasn't felt right (this happened almost 10 years ago now which I recall vividly) so if anybody has any input on it, it would be very much appreciated.
old_master
04-03-2008, 11:09 PM
The "quick fix" may have been a thermal limit switch, does that sound familiar?
If the compressor hub bearing wears out, the clutch will rub against the clutch hub and can make a "crazy whining/wheezing type noise". Depending on how severe the damage is to the bearing, it's possible to replace just the bearing. If the bearing damage is too severe, then the entire compressor needs to be replaced.
If the compressor needs to be replaced, the refrigerant system will have to be retro fitted to accept the new refrigerant, (R134a). R12 is what came in your system originally, but it's no longer legal to install it.
If the compressor hub bearing wears out, the clutch will rub against the clutch hub and can make a "crazy whining/wheezing type noise". Depending on how severe the damage is to the bearing, it's possible to replace just the bearing. If the bearing damage is too severe, then the entire compressor needs to be replaced.
If the compressor needs to be replaced, the refrigerant system will have to be retro fitted to accept the new refrigerant, (R134a). R12 is what came in your system originally, but it's no longer legal to install it.
brcidd
04-04-2008, 09:35 AM
Hate to dissagree- but R-12 is not illegal to install- least not in the US. The system does not have to be converted. R-12 is still available and plentiful. It is just necessary to have a license to handle it. There are many vehicles that still have it in their systems. Any shop who says it is illegal- just wants to not be bothered by it, conversion to 134a in their minds is the easiest route- but not necessarily the best.
at1212b
04-04-2008, 04:33 PM
The "quick fix" may have been a thermal limit switch, does that sound familiar?
Is there a specific reason to engage/disengage it?
Hmm, I'm not sure of that specific term, but I defintely think that's what it was based on what I was told. Could the hub clutch just break due to the serpentine belt and therefore cause the AC compressor to break? The AC was working fine before the alignment of the belt was off.
After the engine bracket/serpentine belt was fixed, there was no noise anymore, but just that the AC wasn't working.
The gut feeling I had was they somehow turned the switch off to say it was broken try to make the sale of a rebuilt compressor as the guy was a bit shady (though I could be wrong).
I'm actually located in Canada, so I'm not sure of the exact specifications, though I think it does have to be converted but he was willing to sell a rebuilt R12 compressor. But in any case, I would definitely take it to a professional.
Is there a specific reason to engage/disengage it?
Hmm, I'm not sure of that specific term, but I defintely think that's what it was based on what I was told. Could the hub clutch just break due to the serpentine belt and therefore cause the AC compressor to break? The AC was working fine before the alignment of the belt was off.
After the engine bracket/serpentine belt was fixed, there was no noise anymore, but just that the AC wasn't working.
The gut feeling I had was they somehow turned the switch off to say it was broken try to make the sale of a rebuilt compressor as the guy was a bit shady (though I could be wrong).
I'm actually located in Canada, so I'm not sure of the exact specifications, though I think it does have to be converted but he was willing to sell a rebuilt R12 compressor. But in any case, I would definitely take it to a professional.
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