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88 DeVille a/c pressure line muffler


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Cadillac A/C experts,

Well, it happened. The compressor died a black death a couple of months after the 134a conversion. I am putting it back together now. New (reman) compressor, accum., new condenser, and filter/oriface. I flushed the evap and the high pr line to the evap. The hi pr line from the compressor to the condensor however, has the muffler. I think it is partically clogged. What can I use to emulsify the contamination in there? Or should the muffled be eliminated from the line altogether?

Any recommendations would be greatly.

Bill

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Cadillac A/C experts,

Well, it happened. The compressor died a black death a couple of months after the 134a conversion. I am putting it back together now. New (reman) compressor, accum., new condenser, and filter/oriface. I flushed the evap and the high pr line to the evap. The hi pr line from the compressor to the condensor however, has the muffler. I think it is partically clogged. What can I use to emulsify the contamination in there? Or should the muffled be eliminated from the line altogether?

Any recommendations would be greatly.

Bill

You cannot flush through a muffler. The line needs to be replaced. If it's not available from GM, you can have one made. There are hose fabricators that can make A/C lines.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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:( I thought that is what you were going to say. But, should the new hose have a muffler? Or can it be eliminated?

Thanks

You can eliminate the muffler and the system will work fine.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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One last question. The new reman compressor had oil in it right from the box. I turned the clutch assembly by hand with the clutch facing down to pre lube the shaft seal. Now the system is all put together and I'm ready to pressure test and evacuate. The specs call for PAG oil. Would that have been PAG in the new compressor, (because it is a Cadillac spec HR6 compressor)?

Or do I pull the compressor and drain the oil?

Thanks.

Bill

1988 Sedan Deville 4.5L

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One last question. The new reman compressor had oil in it right from the box. I turned the clutch assembly by hand with the clutch facing down to pre lube the shaft seal. Now the system is all put together and I'm ready to pressure test and evacuate. The specs call for PAG oil. Would that have been PAG in the new compressor, (because it is a Cadillac spec HR6 compressor)?

Or do I pull the compressor and drain the oil?

Thanks.

Bill

1988 Sedan Deville 4.5L

Is this a chain store remanufactured compressor or a Delco/GM remanufactured compressor? Usually compressors are not shipped with PAG oil in them as the PAG oil is hydroscopic.

If the remanufactured compressor has oil in it, I bet it is mineral oil for R-12. Mineral oil will not be carried by the R-134a. If you are going to stay with R-134a, remove the compressor, drain the oil from the compressor and then flush it with PAG-150 viscosity oil. After you drain the oil, turn the clutch hub by hand until the additional oil is pumped out of the discharge port. Now add PAG-150 oil to the suction port while turning the clutch hub until you see clean PAG oil coming out the discharge port. Keep track on how much of the PAG oil you use while flushing. Add an additional amount to bring the total to equal 8 oz total to the new accumulator. Reinstall the compressor.

The system oil capacity is 8 oz (check the label on your old accumulator to be sure). I know 8 oz is the quantity for ther Northstar equipped cars but double check.

Next, you will need to evacuate and charge the system. Some auto parts stores rent vacuum pumps and gages for A/C service but you may need to take the car to a shop to have this procedure done. Do not skip the evacuation step - you must draw a vacuum on the system in order to remove all moisture and air. Air in the system will affect cooling performance and increase head pressures. Moisture will react with the refrigerant to form acids that will eat away at the system or freeze in the orifice tube and result in poor cooling performance.

Hopefully, you bought your R-134a before the prices went through the roof...

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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Yes, I bought the reman compressor fro Autozone. I have a vacumm pump and guages. I will pull the compressor and flush/cycle in PAG 150. Thanks for the tips and help. 8oz is correct.

Bill

1988 Sedan Deville 4.5

Just trying to keep the old girl on the road.

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Charge the same amount of R-134a as what is called out for R-12 or you will get a low refrigerant code.

Post back your results.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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Ok, it been 8 days since the A/C overhaul. The system is working great (without the muffler). I had a local shop rebuild the pressure lines for $34. I am getting 52 degrees F at the side vents. No codes. I put in 30oz 134a and 8 oz PAG. Vac to 28.5psi for 45 minutes.

Thanks for all help.

Bill

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Ok, it been 8 days since the A/C overhaul. The system is working great (without the muffler). I had a local shop rebuild the pressure lines for $34. I am getting 52 degrees F at the side vents. No codes. I put in 30oz 134a and 8 oz PAG. Vac to 28.5psi for 45 minutes.

Thanks for all help.

Bill

Glad to hear your A/C is fixed. Do you notice any increased noise due to eliminating the muffler from the A/C line?

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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