The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Getting up the nerve to tackle A/C, need to remove the old

*randy500* · 07-15-2019, 12:28 PM

Your going with a shotgun approach under the hood which will probably fix your leak and get you a bunch of cheap looking and I’ll fitting parts.
I would suggest finding your leak or replacing components that are likely leaking.
Your leak is probably the high pressure rubber line and the large o-rings that seal each one of the compressor. Often those only leak under high pressure and can’t be found by pulling a vacuum.
I pressurize the system using nitrogen because it’s very dry and you can pressurize it to extreme operating system pressures, 300psi or so and look for leaks with soap and water solution. You could use dry compressed air.
For the least cost most benefit just buy a new compressor four seasons part number 58096, $267 on amazon, it’s metric threads but comes with the metric bolts to mount to stock brackets. Buy a new high pressure line, $40 or so from classic parts.com and o ring kit.
That seals up under hood likely leak points.

Remove the inner fender and hood hinge to remove the inner and outer boxes, you don’t gain anything by removing the engine. Prop up the hood at the rf using a stick, prop up the rear of the hood using a piece of long wood from the cowl to the core support.

The inner box has 2 inside sheet metal screws, 3/8 or 7/16 head, and 4 outside nuts, one by the heater hoses, one below that and 2 on the rh side which are easy to find.
There is usually mucho debris in front of the evaporator which is only accessible by removing the evaporator core.

Inside is easy to work on once you remove the glovebox liner and the radio.
Remove the 3/8 sheet metal screw above the floor vent and the screws holding it and the s duct to the diverter valve, then the inside box. Then remove the control panel.
The repro diverter valve is almost as good as the later gm ones sold about 2 years ago. I’m sure it’s got a broken hinge.
Buy a new cloth type hose set, the plastic replacement ones suck.
Fix all your stripped out holes with j nuts, on the metal or plastic parts, stripped holes in the fiberglass, use resin and toothpicks, then re drill the holes.

07-15-2019, 12:28 PM	#4
randy500 Account Suspended Join Date: Jul 2016 Location: Tacoma, WA Posts: 6,873	Re: Getting up the nerve to tackle A/C, need to remove the old Your going with a shotgun approach under the hood which will probably fix your leak and get you a bunch of cheap looking and I’ll fitting parts. I would suggest finding your leak or replacing components that are likely leaking. Your leak is probably the high pressure rubber line and the large o-rings that seal each one of the compressor. Often those only leak under high pressure and can’t be found by pulling a vacuum. I pressurize the system using nitrogen because it’s very dry and you can pressurize it to extreme operating system pressures, 300psi or so and look for leaks with soap and water solution. You could use dry compressed air. For the least cost most benefit just buy a new compressor four seasons part number 58096, $267 on amazon, it’s metric threads but comes with the metric bolts to mount to stock brackets. Buy a new high pressure line, $40 or so from classic parts.com and o ring kit. That seals up under hood likely leak points. Remove the inner fender and hood hinge to remove the inner and outer boxes, you don’t gain anything by removing the engine. Prop up the hood at the rf using a stick, prop up the rear of the hood using a piece of long wood from the cowl to the core support. The inner box has 2 inside sheet metal screws, 3/8 or 7/16 head, and 4 outside nuts, one by the heater hoses, one below that and 2 on the rh side which are easy to find. There is usually mucho debris in front of the evaporator which is only accessible by removing the evaporator core. Inside is easy to work on once you remove the glovebox liner and the radio. Remove the 3/8 sheet metal screw above the floor vent and the screws holding it and the s duct to the diverter valve, then the inside box. Then remove the control panel. The repro diverter valve is almost as good as the later gm ones sold about 2 years ago. I’m sure it’s got a broken hinge. Buy a new cloth type hose set, the plastic replacement ones suck. Fix all your stripped out holes with j nuts, on the metal or plastic parts, stripped holes in the fiberglass, use resin and toothpicks, then re drill the holes.