Dye on 17 year old Delphi 6628
Posted: Tue Jun 06, 2017 8:26 am
New here to autoacforum and new to working on AC systems.
I'm the original owner. 17 year old GM truck. 200k miles, 4.3L v6. The bluebook on my truck is down to about $1000. I plan to keep the truck for another year or two and absolutely need the AC during the summers up here. Original Delphi 6628 compressor etc. System holds 1.8lbs 134a.
I think the compressor seals are blown (dye on housing), but wondering if maybe it is only a failed high pressure relief valve and hoping I could get by with replacing only the valve. Where does the relief valve discharge? At this point there are only a few PSI in the system. Compressor is fairly quiet when I jump the connector at the pressure switch on the accumulator. Certainly no squealing.
AC worked fine since new, until early last summer when it wasn't cooling very well. The clutch was cycling every 10 seconds. Bought a $60 set of manifold gauges and 134a to bring it into operating range. I didn't add dye or oil. I can't remember too clearly, but pretty sure I didn't top it off, but added only enough to stop the cycling and get some cold air. Blew cold all summer. Have not use it much since last October other than it automatically running when using defrost.
When I started using it again last month, there was no cold air. The static pressure was about 20 PSI. Added a 12 oz can (though it needed more). It lasted only a couple days. Bought a can that included dye. Leak at the switch mounted on the accumulator. It seemed loose when I put a wrench on it, so I just tightened it and added more 134a, aiming fill it and top it off. That leak seems to have stopped. But a week later, it's lost nearly the entire charge.
Now I'm noticing dye around the middle of the compressor, none on the "ends" None of the clutch or hoses or condenser. The middle of the compressor is dark with oil/grim, so much that I couldn't see there was a label. Since the compressor is mounted on top of the engine, i presume the grime is from compressor oil. I suppose the layer of dark grime indicates it's been leaking for a while. The is some pressure in the system when I burp the schrader valve, but it is very low, and it's too low to move the needle on the manifold gauge.
What should I replace? I have a vacuum pump, compressor, LP switch, accumulator and orifice tube on order.
I'm the original owner. 17 year old GM truck. 200k miles, 4.3L v6. The bluebook on my truck is down to about $1000. I plan to keep the truck for another year or two and absolutely need the AC during the summers up here. Original Delphi 6628 compressor etc. System holds 1.8lbs 134a.
I think the compressor seals are blown (dye on housing), but wondering if maybe it is only a failed high pressure relief valve and hoping I could get by with replacing only the valve. Where does the relief valve discharge? At this point there are only a few PSI in the system. Compressor is fairly quiet when I jump the connector at the pressure switch on the accumulator. Certainly no squealing.
AC worked fine since new, until early last summer when it wasn't cooling very well. The clutch was cycling every 10 seconds. Bought a $60 set of manifold gauges and 134a to bring it into operating range. I didn't add dye or oil. I can't remember too clearly, but pretty sure I didn't top it off, but added only enough to stop the cycling and get some cold air. Blew cold all summer. Have not use it much since last October other than it automatically running when using defrost.
When I started using it again last month, there was no cold air. The static pressure was about 20 PSI. Added a 12 oz can (though it needed more). It lasted only a couple days. Bought a can that included dye. Leak at the switch mounted on the accumulator. It seemed loose when I put a wrench on it, so I just tightened it and added more 134a, aiming fill it and top it off. That leak seems to have stopped. But a week later, it's lost nearly the entire charge.
Now I'm noticing dye around the middle of the compressor, none on the "ends" None of the clutch or hoses or condenser. The middle of the compressor is dark with oil/grim, so much that I couldn't see there was a label. Since the compressor is mounted on top of the engine, i presume the grime is from compressor oil. I suppose the layer of dark grime indicates it's been leaking for a while. The is some pressure in the system when I burp the schrader valve, but it is very low, and it's too low to move the needle on the manifold gauge.
What should I replace? I have a vacuum pump, compressor, LP switch, accumulator and orifice tube on order.