david85
Full Access Member
Before pulling my truck off the road for the resto, I used it briefly in some warmer weather. I had recently installed a new receiver dryer since I thought it would be a good idea when I tried out a variable orifice tube. Everything seemed fine after recharging but it was a few days before the real test happened.
While idling in traffic, I started to hear a chirping belt. I tried turning off the AC. Sure enough the sound stopped. Got home and the belt tension was good but the compressor was extremely stiff and I couldn't turn it by hand. My first thought was the compressor was shot.
Then a few days later it tested fine...for a few minutes. Something was gradually loading up. After pulling apart the system, I found the orifice tube was rather forcefully jammed in place under a pipe of oily "grey stuff". I tried cleaning it out and putting it back together but there were still issues. Low side pressure stayed very low so the compressor kept trying to push until the belt couldn't keep up. I had no way of measuring the hot side pressure but I assume it would have been too high.
The compressor didn't appear to be internally leaking. After shutting it off, the hot and cold lines stayed that way so the internal seals and valves appear to be holding. Once the pressure dissipates through the orifice, I can turn it by hand and still hear a slight hiss as small amounts of refrigerant are pushed through.
Not long after, the truck got decommissioned and went under the knife so I wasn't able to pursue the matter further. That was more than a year ago. Now that its back together, I'm trying to plan my attack on this problem.
After doing some reading, It seems this could be the desiccant material coming out and getting pumped through the system until getting clogged in the screen for the orifice. The dryer was ordered new from rockauto at the same time I purchased the variable orifice tube (don't remember exact brand, but think it was 4 seasons).
So what do you think guys? Am I on the right track? Any recommendations for a better brand of orifice tube and dryer? Will I have to replace the compressor now?
While idling in traffic, I started to hear a chirping belt. I tried turning off the AC. Sure enough the sound stopped. Got home and the belt tension was good but the compressor was extremely stiff and I couldn't turn it by hand. My first thought was the compressor was shot.
Then a few days later it tested fine...for a few minutes. Something was gradually loading up. After pulling apart the system, I found the orifice tube was rather forcefully jammed in place under a pipe of oily "grey stuff". I tried cleaning it out and putting it back together but there were still issues. Low side pressure stayed very low so the compressor kept trying to push until the belt couldn't keep up. I had no way of measuring the hot side pressure but I assume it would have been too high.
The compressor didn't appear to be internally leaking. After shutting it off, the hot and cold lines stayed that way so the internal seals and valves appear to be holding. Once the pressure dissipates through the orifice, I can turn it by hand and still hear a slight hiss as small amounts of refrigerant are pushed through.
Not long after, the truck got decommissioned and went under the knife so I wasn't able to pursue the matter further. That was more than a year ago. Now that its back together, I'm trying to plan my attack on this problem.
After doing some reading, It seems this could be the desiccant material coming out and getting pumped through the system until getting clogged in the screen for the orifice. The dryer was ordered new from rockauto at the same time I purchased the variable orifice tube (don't remember exact brand, but think it was 4 seasons).
So what do you think guys? Am I on the right track? Any recommendations for a better brand of orifice tube and dryer? Will I have to replace the compressor now?