AC Troubleshooting

[scotty1998]

Can someone just check my sanity? I am trying to pull vac on my ac system while the service valves are in the neutral (service) positions. No matter what I do, vac will not hold. I'm relatively sure that I have all of my fittings tight and I just want to tell you all the troubleshooting I've gone through and why I think the compressor is leaking.

If I turn the service valves all the way clockwise, this isolates the compressor. If I draw vacuum independently on both the high and low sides, vac holds fine. This would mean that the compressor is the culprit, right?

Thanks .

[Chevelleguy]

Are you converting it? 134 is cheap enough last time a checked. You could just shoot a can in and see where it leaks out. Some times, that is your only choice to find it.

[scotty1998]

Already converted. Just trying to fire everything back up after replacing a hose. It's definitely leaking. You can watch the gauge drop and it returns to ambient pressure in about 2 minutes.

[sonoraed]

add a couple of oz 134a and listen for leaks or spray with soapy water, that kind of leak should be easy to find
I would replace those backseating service valves with valves that have schraeder valves and 134a ports,makes life a little easier

[babywag]

Can someone just check my sanity? I am trying to pull vac on my ac system while the service valves are in the neutral (service) positions. No matter what I do, vac will not hold. I'm relatively sure that I have all of my fittings tight and I just want to tell you all the troubleshooting I've gone through and why I think the compressor is leaking.

If I turn the service valves all the way clockwise, this isolates the compressor. If I draw vacuum independently on both the high and low sides, vac holds fine. This would mean that the compressor is the culprit, right?

Thanks .

If you turn the service valves all the way in the compressor is isolated from the system and safe to remove.
Drawing a vacuum when the valves are in this position *and* vacuum holding would indicate the compressor is NOT leaking.

[scotty1998]

Ok, by revisiting the diagrams for the valve ops on Tom's old Jeep web site I figured out why I was confused. Diagrams a and B are reversed. A is actually showing the compressor isolation position, not normal ops as indicated. I see now why full clockwise position indicates that the compressor isn't leaking. Soap and water next. ThNx guys.