Refrigerant Type: CFC-12
Ambient Temp: 75F
Pressure Low: vac
Pressure High: 60
Country of Origin: Japan
Got this car a while ago. When I got it, the system was completely empty. I pulled a vacuum and it held it ok, so I charged it with specified amount of R12 by weight.
The compressor engages, then after 5 minutes or so, it makes clanking noise similar to an MRI machine. The pressure corresponds to acoustic noise, but the fluctuation isn't so dramatic.
This car uses a TXV.
No cooling at all, inside or feeling along the lines. Suction by compressor actually feels hot. I can't feel any heat at the condenser, but I can see liquid dancing around in sight glass at receiver-drier.
Low side drops to vacuum.
High side is 60-70 psi
Both low and high service ports are right near the compressor, so if there's an obstruction on high-side, I would imagine there will be an excess pressure on high side.
If it's the compressor, I don't know why low side pulls into vacuum and if it's just the TXV, I don't see why the high side is so low.
One shop feels that the noise is due to obstruction, but allowing high side to bypass into low side through manifold doesn't relieve the clattering noise.
Where do I go from here? I don't want to replace more parts than needed, but I don't want to have to remove charge from the system again. I've already had to do that once.
What is the static pressure? Looks like the refrigerant is almost all gone. If it leaked down to zero once it's going to do it again.
If it is still full, there must be a restriction somewhere inbetween the compressor and the high side port. The noise you are hearing could be due to very high pressure at the compressor which you aren't seeing at the port.
Edited: Sun May 13, 2012 at 9:47 AM by mk378
Well, so far you have a leak, and a bad compressor.
The only answer is to locate the leak(s) then recover the system.
The compressor is junk if it makes as much noise as an MRI. You have an obstruction someplace, perhaps a TXV that is rusted shut.
The dryer needs to be replaced. Pull the TXV & inspect it - or just replace it for less than 50 bucks. The evaporators can usually be flushed.
The condensors on those cars we either tube & fin or serpentine - depending on the whim of Fuji Heavy Industry. If you have a tube & fin it can be flushed. If you have the serpentine, it is probably trashed with pieces of clanging compressor and should be replaced. You can't flush a serpentine, and small pieces of compressor can block enough of it's passages to make it worthless - but you can still blow air through it.
You are looking at 650 bucks in parts to do it right if you have a serpentine condensor, and 450 with a tube & fin. New compressor is 350 from AMA, 50 bucks in the TXV & 20 for a new dryer. Add some O rings & oil.
Patch it up & I can bet you will spend twice that over 2 years and only have A/C for about 2 months of that 2 years - but you will get to work on it a lot more.
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.
With a totally blocked TXV, all the refrigerant would fill up the receiver and condenser and sit there at a low pressure, though it would need about 60 degree ambient to stay at 60 psi. I agree with Bohica that loud noise from inside the compressor means that it is done.
Edited: Sun May 13, 2012 at 6:53 PM by mk378
We've updated our forums!
Click here to visit the new forum
Copyright © 2016 Arizona Mobile Air Inc.