1997 Ram diesel, high suction pressure, low discharge, need help

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12valve
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1997 Ram diesel, high suction pressure, low discharge, need help

Post by 12valve »

In a nutshell:

Compressor was short-cycling, 1 second on, 2 seconds off, constantly, no cold air. The static pressures were equal on both sides, but when I started it up I had as high as 90 on the low side, but only 125 max on the high side, dropping down to 90 when it cycled. Ambient temp outside was roughly 75.

I tried to add refrigerant through the low side (through my manifold gauges) to see if I could slowly bring the high side up, to no avail. I evacuated the system, and pulled the orifice tube. It was clean. I found evidence of refrigerant oil at the manifold hose assembly connection to the compressor, so I replaced the sealing washers. I put the system in a vacuum, and it held 28Hg for a few hours.

I then tried to charge off a can into the low side, but it will not take it, maybe only an ounce or two. I had made sure to carefully purge all lines of air before I did. When I open the low side valve, my gauge will rise to nearly 100 psi, but almost no refrigerant enters the system, like there's a restriction in the low side preventing any refrigerant from going in. When I jump the compressor it will not draw it in. I have verified that the schrader is indeed being pressed. I have to turn it off because it starts getting hot.

Am I dealing with a compressor which won't pump? The fan clutch pulls air hard. I can put a rag in front of the condenser and it sticks to it. I have the blower on high and the ac on max. There are no gross leaks as I've had the truck 4 years and it still had some refrigerant in it. I am willing to buy a compressor if need be, but want to make sure that's my problem. Any help is greatly appreciated. Thank you.
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Tim
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Re: 1997 Ram diesel, high suction pressure, low discharge, need help

Post by Tim »

No control valve in this model compressor. So if it not pumping and clutch engaged, dead compressor.
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12valve
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Re: 1997 Ram diesel, high suction pressure, low discharge, need help

Post by 12valve »

Thanks for the reply. It ended up being faulty equipment. The low side hose on my brand new Chinese FJC manifold gauge assembly had a complete blockage where the washer/gasket was supposed to be. It would intermittently feed pressure back to the gauge, but not accept refrigerant. I had ended up charging the system through the high side with the vehicle off and the refrigerant in a bucket of hot water. I finally took the gauges apart and found, to my disgust, the problem.
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Tim
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Re: 1997 Ram diesel, high suction pressure, low discharge, need help

Post by Tim »

Good deal. Cheaper than a comprssor replacement.
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tbirdtbird
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Re: 1997 Ram diesel, high suction pressure, low discharge, need help

Post by tbirdtbird »

Fai, you just posted on a 5 year old thread. We have another dude on here doing the same, or is that guy really you.
You have contributed nothing to this forum which is intended for serious posters.
Suggest you find a different forum to dilute or better yet a different hobby.
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
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