Function Test
| Mode Control | Temp Control | Fan Switch | Blower Speed | Heater Outlets | Defroster Outlets | See Remarks |
|---|---|---|---|---|---|---|
| Before beginning the functional test of the heater system, ensure that the vehicle is idling with the coolant hot and the thermostat open. Ensure that the coolant temperature is 90°C (194°F). Even if a problem is found during any intermediate step of the functional test, complete the test before the repair begins. | ||||||
| Off | Cold | Off | No Air Flow | No Air Flow | ||
| Vent | Cold | High | High | No Air Flow | No Air Flow | A,B |
| Heater | Hot | High | High | Air Flow | Min Air Flow | A,B |
| Blend | Hot | High | High | Air Flow | Air Flow | A,B |
| Def | Hot | High | High | Min Air Flow | Air Flow | A,B |
| A. Engage the detent in each mode. B. Some air bleed will occur through defroster and side window defogger vents in heat mode. | ||||||
Function Test
System Performance Test (Pickups - Non Utilities)
Use this test and the accompanying chart in order to aide in the evaluation of the air conditioning (A/C) system performance. While increased engine RPM may provide extra capacity and cooler A/C discharge temperatures, the test results may not be repeatable due to other variables. The following test procedure must be followed.
- Park the vehicle indoors or in a shaded area.
- Engage the parking brake.
- Open the hood, the doors, and the windows in order to ventilate the interior.
- Vent the engine exhaust, if necessary.
- Install the high and the low side pressure gauges.
- Record the ambient temperature at the vehicle.
- Record the temperature and the relative humidity by using a psychrometer or by consulting the local weather bureau.
- Close the doors.
- Close all of the windows.
- Place the transmission in park (auto) or in neutral (manual).
- Start the engine.
- Set the mode control to the upper mode setting.
- Depress the A/C and the Max/Recirculation buttons.
- Set the blower speed to the HIGH position.
- Set the temperature control to the FULL COLD position.
- Open the A/C outlets.
- Install a temperature tester into the left center A/C outlet.
- Stabilize the engine speed to idle RPM.
- Start the timer.
- Operate the A/C system for about 5 minutes or until the left center outlet reaches the lowest temperature.
- Record the following data: The left outlet air temperature The high-side pressure The low-side pressure
- Turn the ignition off.
- Compare the readings with the following table.
- Normally operating A/C systems should be within 5 degrees and 10-20 PSIG of the levels appearing in the table.
| Relative Humidity | Ambient Air Temperature | Maximum Low Side Pressure | Engine Speed | Maximum Left Center Air Outlet Temperature | Maximum High Side Pressure |
|---|---|---|---|---|---|
| 20% | 21°C (70°F) | 223 kPa (32 psi) | Idle | 7°C (45°F) | 1 138 kPa (165 psi) |
| 20% | 27°C (80°F) | 239 kPa (35 psi) | Idle | 8°C (47°F) | 1 255 kPa (182 psi) |
| 20% | 32°C (90°F) | 277 kPa (35 psi) | Idle | 12°C (53°F) | 1 469 kPa (213 psi) |
| 20% | 38°C (100°F) | 330 kPa (48 psi) | Idle | 16°C (60°F) | 1 737 kPa (252 psi) |
| 20% | 43°C (110°F) | 385 kPa (56 psi) | Idle | 19°C (67°F) | 2 020 kPa (293 psi) |
| 30% | 21°C (70°F) | 230 kPa (33 psi) | Idle | 10°C (49°F) | 1 269 kPa (184 psi) |
| 30% | 27°C (80°F) | 268 kPa (39 psi) | Idle | 11°C (52°F) | 1 400 kPa (203 psi) |
| 30% | 32°C (90°F) | 323 kPa (47 psi) | Idle | 15°C (59°F) | 1 648 kPa (239 psi) |
| 30% | 38°C (100°F) | 376 kPa (55 psi) | Idle | 19°C (66°F) | 1 862 kPa (270 psi) |
| 30% | 43°C (110°F) | 430 kPa (62 psi) | Idle | 22°C (72°F) | 2 103 kPa (305 psi) |
| 40% | 21°C (70°F) | 250 kPa (36 psi) | Idle | 10°C (49°F) | 1 269 kPa (184 psi) |
| 40% | 27°C (80°F) | 293 kPa (43 psi) | Idle | 12°C (54°F) | 1 462 kPa (212 psi) |
| 40% | 32°C (90°F) | 341 kPa (50 psi) | Idle | 17°C (62°F) | 1 682 kPa (244 psi) |
| 40% | 38°C (100°F) | 391 kPa (57 psi) | Idle | 20°C (68°F) | 1 931 kPa (280 psi) |
| 50% | 21°C (70°F) | 248 kPa (36 psi) | Idle | 10°C (50°F) | 1 241 kPa (180 psi) |
| 50% | 27°C (80°F) | 296 kPa (43 psi) | Idle | 13°C (56°F) | 1 448 kPa (210 psi) |
| 50% | 32°C (90°F) | 355 kPa (52 psi) | Idle | 18°C (65°F) | 1 675 kPa (243 psi) |
| 50% | 38°C (100°F) | 417 kPa (61 psi) | Idle | 21°C (70°F) | 1 999 kPa (290 psi) |
| 60% | 21°C (70°F) | 251 kPa (36 psi) | Idle | 11°C (51°F) | 1 227 kPa (178 psi) |
| 60% | 27°C (80°F) | 300 kPa (44 psi) | Idle | 14°C (57°F) | 1 420 kPa (206 psi) |
| 60% | 32°C (90°F) | 365 kPa (53 psi) | Idle | 19°C (66°F) | 1 689 kPa (245 psi) |
| 60% | 38°C (100°F) | 427 kPa (62 psi) | Idle | 22°C (71°F) | 1 999 kPa (290 psi) |
| 70% | 21°C (70°F) | 256 kPa (37 psi) | Idle | 10°C (50°F) | 1 234 kPa (179 psi) |
| 70% | 27°C (80°F) | 299 kPa (43 psi) | Idle | 14°C (57°F) | 1 420 kPa (206 psi) |
| 70% | 32°C (90°F) | 379 kPa (55 psi) | Idle | 19°C (66°F) | 1 737 kPa (252 psi) |
| 80% | 21°C (70°F) | 254 kPa (37 psi) | Idle | 10°C (50°F) | 1 200 kPa (174 psi) |
| 80% | 27°C (80°F) | 305 kPa (44 psi) | Idle | 14°C (57°F) | 1 407 kPa (204 psi) |
| 80% | 32°C (90°F) | 387 kPa (56 psi) | Idle | 19°C (67°F) | 1 717 kPa (249 psi) |
| This is not a maximum A/C Capacity Test. Increased engine temperatures may not provide repeatable test results. | |||||
System Performance Test (Pickups)
System Performance Test (Suburban/Yukon XL - Utilities)
Use this test and the accompanying chart in order to aide in the evaluation of the air conditioning (A/C) system performance. While increased engine RPM may provide extra capacity and cooler A/C discharge temperatures, the test results may not be repeatable due to other variables. The following test procedure must be followed.
- Park the vehicle indoors or in a shaded area.
- Engage the parking brake.
- Open the hood, the doors, and the windows in order to ventilate the interior.
- Vent the engine exhaust, if necessary.
- Install the high and the low side pressure gauges.
- Record the ambient temperature at the vehicle.
- Record the temperature and the relative humidity by using a psychrometer or by consulting the local weather bureau.
- Close the doors.
- Close all of the windows except the driver's window. Leave the driver's window open 5 inches.
- Place the transmission in park (auto) or in neutral (manual).
- Start the engine.
- Set the mode control to the upper mode setting.
- Depress the A/C and the Max/Recirculation buttons.
- Set the blower speed to the HIGH position.
- Set the temperature control to the FULL COLD position.
- Open the A/C outlets.
- Install a temperature tester into the left center A/C outlet.
- Stabilize the engine speed to idle RPM.
- Start the timer.
- Operate the A/C system for about 5 minutes or until the left center outlet reaches the lowest temperature.
- Record the following data: The left outlet air temperature The high-side pressure The low-side pressure
- Turn the ignition off.
- Compare the readings with the following table.
- Normally operating A/C systems should be within 5 degrees and 10-20 PSIG of the levels appearing in the table.
| % Relative Humidity | Ambient Air Temperature (°F/°C) | Maximum Low Side Pressure (psig/kpa) | Engine Speed | Maximum Front System Left Center Air Outlet Temperature (°F) | Maximum Rear System 3rd Seat Right Air Outlet Temperature (°C/°F) | Maximum High Side Pressure (psig/kpa) |
|---|---|---|---|---|---|---|
| 10 | 110/43 | 54/372 | Idle | 64/18 | 66/19 | 248/1710 |
| 15 15 | 100/38 120/49 | 46/317 57/393 | Idle Idle | 58/14 66/19 | 61/16 67/19 | 211/1455 281/1937 |
| 20 20 20 | 80/27 90/32 110/43 | 31/214 38/262 54/372 | Idle Idle Idle | 44/7 50/10 65/18 | 47/8 54/12 67/19 | 143/986 174/1200 250/1724 |
| 30 30 | 100/38 110/43 | 46/317 55/379 | Idle Idle | 58/14 66/19 | 60/16 68/20 | 211/1455 253/1744 |
| 40 40 | 80/27 90/32 | 32/221 39/269 | Idle Idle | 45/7 52/11 | 48/9 55/13 | 142/979 176/1214 |
| 45 45 | 80/27 100/38 | 26/179 48/331 | Idle Idle | 38/3 60/16 | 42/6 62/17 | 116/800 214/1476 |
| 60 60 | 80/27 90/32 | 32/221 41/283 | Idle Idle | 45/7 54/12 | 48/9 56/13 | 145/1000 178/1227 |
| 70 | 70/21 | 27/186 | Idle | 39/4 | 42/6 | 117/807 |
| 75 | 60/16 | 34/234 | Idle | 47/8 | 50/10 | 75/517 |
System Performance Test (Suburban/Yukon XL)
Leak Testing
| CAUTION | Avoid breathing A/C Refrigerant-134a and lubricant vapor and mist. Exposure may irritate eyes, nose and throat. To remove R-134a from the A/C system, use service equipment certified to meet the requirements of SAE J2210 (R-134a recycling equipment). If accidental system discharge occurs, ventilate work area before resuming service. Additional health and safety information may be obtained from refrigerant and lubricant manufacturers. |
Perform a refrigerant leak test on the system whenever you suspect a leak. Perform a refrigerant leak test on the system following a service operation that disturbs the components, the lines, or the connections. Many methods and special tools are available for this purpose. However, no matter which tool is used, care and diligence are the biggest keys to success.
Test Procedure
| CAUTION | Take care to prevent personal injury which could occur due to touching a hot engine when testing. Tests should be done with the engine "Off" and as cool as possible. Do not operate the detector in a combustible atmosphere since its sensor operates at high temperature. |
| IMPORTANT | Always follow the refrigerant system in a continuous path, so that no areas of potential leaks are missed. Always test all of the areas listed below in order to make sure the entire system is leak-free, even when one leak is already found. |
Use this procedure in order to test the following components and locations in the system
- The evaporator inlet and outlet
- The accumulator inlet and outlet
- The condenser inlet and outlet
- All of the brazed and welded areas
- The areas showing signs of damage
- The hose couplings
- The compressor rear head
- The housing joints
CCOT Air Conditioning (A/C) System Diagnosis
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| 1 | Inspect the following components of the air conditioning (A/C) system: The fuses The wire connectors The blower fan operation Did you find and repair a condition? | System OK | Go to Step 2 | |
| 2 | Is the drive belt loose, missing, or damaged? | Go to Step 4 | Go to Step 3 | |
| 3 | IMPORTANT: The ambient temperature must be above 10°C (50°F) for completion of this diagnostic procedure. Use the following steps in order to inspect the compressor clutch engagement: Start the engine. Idle the engine at approximately 1000 RPM. Set the A/C control assembly to the NORM position. Set the blower to the HIGH position. Place an auxiliary fan in front of the vehicle. Observe the clutch operation for a period of 5 minutes. Does the clutch engage or cycle? | Go to Step 7 | Go to Step 11 | |
| 4 | Has the compressor seized? | Go to Step 5 | Go to Step 6 | |
| 5 | Replace the compressor assembly. Refer to Compressor Replacement (LR4, LM7, LQ4 w/ Denso ) or Compressor Replacement (L35 w/ Harrison) or Compressor Replacement (LR4, LM7, LQ4 w/Harrison) . Does the A/C system operate properly? | System OK | Go to Step 6 | |
| 6 | Tighten or replace the belt, as needed. Does the A/C system operate properly? | System OK | Go to Step 3 | |
| 7 | Feel the liquid line before the orifice tube. Is the liquid line cold? | Go to Step 8 | Go to Step 9 | |
| 8 | Inspect the high side of the system for a frost spot in order to locate a restriction. Repair the restriction. Conduct a leak test of the system. Refer to Leak Testing . Is the A/C system operating properly? | System OK | Go to Step 9 | |
| 9 | Feel the evaporator inlet pipe. Feel the evaporator outlet pipe. Is the inlet pipe colder than the outlet pipe? | Go to Step 10 | Go to Step 24 | |
| 10 | Conduct a leak test of the system. Refer to Leak Testing . Repair any leaks as necessary. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the A/C system operating properly? | System OK | Go to Step 20 | |
| 11 | Connect a fused jumper wire from the compressor hot lead to the positive battery post. Observe the compressor operation. Does the compressor clutch engage? | Go to Step 12 | Go to Step 18 | |
| 12 | Remove the jumper. Measure the pressure at the accumulator fitting. Is the pressure below the specified value? | 483 kPa (70 psi) | Go to Step 13 | Go to Step 15 |
| 13 | Measure the refrigerant pressure on the high side of the system. Is the pressure above the specified value? | 483 kPa (50 psi) | Go to Step 14 | Go to Step 10 |
| 14 | Recover the refrigerant. Inspect for the following conditions: A plugged orifice A restriction in the high side of the system Complete the necessary repairs, or replace the orifice. Evacuate the system. Charge the system. Conduct a leak test of the system. Refer to Leak Testing . Is the A/C system operating properly? | System OK | Go to Step 10 | |
| 15 | Connect a fused jumper wire between the pressure switch and the positive battery post. Does the compressor operate? | Go to Step 16 | Go to Step 17 | |
| 16 | IMPORTANT: Do not recover the refrigerant. The fitting has a Schrader Valve®. Replace the pressure switch. Refer to Pressure Cycling Switch Replacement in HVAC Systems - Manual.Is the A/C system operating properly? | System OK | Go to Step 7 | |
| 17 | Inspect the pressure switch for an open circuit or a broken wire. Complete any necessary repairs. Is the A/C system operating properly? | System OK | Go to Step 7 | |
| 18 | Apply an external ground to the compressor. Does the compressor clutch engage? | System OK | Go to Step 19 | |
| 19 | Replace the clutch coil. Refer to Compressor Clutch Coil Removal (Harrison) or Compressor Clutch Coil Removal (Denso) . Is the A/C system operating properly? | System OK | Go to Step 12 | |
| 20 | Add 0.45 kg (1 lb) of refrigerant to the system. Inspect the clutch cycle rate. Is the clutch cycle rate greater than the specified value? | 8 cycles/minute | Go to Step 21 | Go to Step 22 |
| 21 | Recover the refrigerant. Inspect the system for a plugged orifice. Repair the orifice as necessary. Evacuate the system. Charge the system. Does the air conditioning system operate properly? | System OK | Go to Step 11 | |
| 22 | Feel the evaporator inlet pipe. Feel the evaporator outlet pipe. Is the inlet pipe colder than the outlet pipe? | Go to Step 23 | System OK | |
| 23 | Add 0.45 kg (1 lb) of refrigerant to the system. Feel the evaporator inlet pipe. Feel the evaporator outlet pipe. Is the inlet pipe colder than the outlet pipe? | Go to Step 21 | System OK | |
| 24 | Install a gauge set. Inspect the compressor cycling pressure. Does the compressor cycle on within the specified value range? | 280-350 kPa (41-51 psi) | Go to Step 25 | Go to Step 27 |
| 25 | Does the compressor cycle off within the specified value range? | 140-190 kPa (20-28 psi) | Go to Step 26 | Go to Step 27 |
| 26 | Set the A/C control assembly to the MAX position. Set the temperature setting to full cold position. Set the blower to the HIGH position. Stabilize the engine speed for 5 minutes. Install a thermometer in the left center air outlet. Perform the Performance Test. Refer to System Performance Test (Pickups) or System Performance Test (Suburban/Yukon XL) . Is the temperature performance within the limits of the test specifications? | System OK | Go to Step 10 | |
| 27 | Does the compressor cycle high on above the specified value? | 350 kPa (51 psi) | Go to Step 28 | Go to Step 29 |
| 28 | Does the compressor cycle OFF below the specified value? | 140 kPa (20 psi) | Go to Step 16 | Go to Step 29 |
| 29 | Disconnect the blower wire. Determine when the compressor cycles OFF. Does the compressor cycle off below the specified value range? | 140 kPa (20 psi) | Go to Step 16 | Go to Step 30 |
| 30 | Reconnect the blower motor wire. Is the wire reconnected? | Go to Step 26 | ||
| 31 | Observe the compressor cycling. Does the compressor cycle ON continuously? | Go to Step 32 | Go to Step 21 | |
| 32 | Recover the refrigerant. Inspect the orifice. Is the orifice missing? | Go to Step 33 | Go to Step 34 | |
| 33 | Install the orifice. Evacuate the system. Charge the system. Does the A/C system operate properly? | System OK | Go to Step 34 | |
| 34 | Inspect the suction line. Is the suction line restricted? | Go to Step 35 | Go to Step 36 | |
| 35 | Repair the suction line, as required. Evacuate the system. Charge the system. Does the A/C system operate properly? | System OK | Go to Step 36 | |
| 36 | Evacuate the system Charge the system Does the A/C system operate properly? |
| IMPORTANT |
|---|
| The ambient temperature must be above 10°C (50°F) for completion of this diagnostic procedure. |
| IMPORTANT |
|---|
| Do not recover the refrigerant. The fitting has a Schrader Valve®. |
CCOT Air Conditioning (A/C) System Diagnosis
Noise Diagnosis
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| IMPORTANT: A constant air rush is typical of all heater systems. Some systems may be louder than others. If possible, inspect a similar vehicle in order to determine whether the noise is typical or excessive. | ||||
| 1 | Inspect all the electrical connections and the grounds for proper connections. If a connection is doubtful, use a voltmeter in order to test for constant voltage at the blower motor. Is the repair complete? | Go to Step 2 | ||
| 2 | Sit in the vehicle with the doors and windows closed. With the ignition switch in the ON position and the engine off, start the blower on the HI mode. Select full COLD on the temperature rotary knob. Cycle through the blower speeds, modes and temperature valve positions in order to find where the noise occurs. Define the noise as one of the following types: An air rush A whine A tick/click A squeal/screech A flutter A rumble A scrape If possible, compare the noise with another vehicle of the same model in order to determine if the noise is typical. Is the noise typically a flutter or a rumble that is constant at high blower speeds in certain modes, but can be eliminated at lower blower speeds? | Go to Step 3 | Go to Step 5 | |
| 3 | With the blower on HI, inspect the full HOT to the full COLD temperature positions in all modes. Is the noise audible in all modes and in all temperature positions? | Go to Step 4 | Go to Step 7 | |
| 4 | Inspect the system for obstructions or foreign materials between the fan and the temperature valve. Remove, repair, or replace the fan and the temperature valve as necessary. Retest the system for the noise. Is the noise audible? | Go to Step 2 | System OK | |
| 5 | Feel the blower armature in order to check for vibration of the motor and the fan at each blower speed. Is the vibration excessive? | Go to Step 6 | Go to Step 9 | |
| 6 | Examine the blower fan for wear spots, cracked blades, or a cracked hub. Examine the blower case for wear spots. Repair or replace parts as necessary. Retest the system for the blower noise. Did you find and correct the condition? | System OK | Go to Step 10 | |
| 7 | Is the noise audible in all modes, but not audible in all temperature positions? | Go to Step 8 | Go to Step 11 | |
| 8 | Inspect the temperature valve seals. Repair or replace the temperature valve seals as necessary. Retest the system for the noise. Is the repair complete? | System OK | ||
| 9 | Remove the blower motor and fan assembly. Refer to Blower Motor and Fan Replacement Inspect for foreign material at the orifice of the blower inlet. Repair or replace the blower motor and fan assembly as necessary. Recheck the system for the noise. Did you find and correct the condition? | System OK | Go to Step 6 | |
| 10 | Replace the blower motor and fan assembly. Refer to Blower Motor and Fan Replacement Retest the system for the noise. Did you complete the replacement? | System OK | Go to Step 12 | |
| 11 | Inspect the ducts of the noisy modes for obstructions. Remove any obstructions. Inspect the seals of the suspected mode air valves. Repair or replace the valves as necessary. Refer to Mode Valve Replacement . Retest the system for the noise. Is the repair complete? | System OK | ||
| 12 | Is the noise a click/tick or a whine? | Go to Step 13 | Go to Step 3 | |
| 13 | Replace the blower motor with a second new blower motor. Refer to Blower Motor and Fan Replacement Did you complete the replacement? | System OK | Go to Step 14 | |
| 14 | Reinstall the original blower motor. Refer to Blower Motor and Fan Replacement Is the repair complete? | Go to Step 3 | ||
| IMPORTANT |
|---|
| A constant air rush is typical of all heater systems. Some systems may be louder than others. If possible, inspect a similar vehicle in order to determine whether the noise is typical or excessive. |
Noise Diagnosis
Compressor Leak Testing
Tools Required
- J 39893 Pressure Testing Connector. See «Special Tools»(ref-235300-S01064053572006061900000) .
- J 39500-B R134a A/C Refrigerant Recovery, Recycling and Recharging System (ACR4). See «Special Tools»(ref-235300-S01064053572006061900000) .
- J 34992 Compressor Holding Fixture. See «Special Tools»(ref-235300-S01064053572006061900000) .
- J 39400 Leak Detector. See «Special Tools»(ref-235300-S01064053572006061900000) .
- Install the J 39893 on the rear head of the compressor. See «Special Tools»(ref-235300-S01064053572006061900000) .
- Using the J 39500-B , attach the center hose of the manifold gauge set on the charging station to a refrigerant drum standing in an upright position. See «Special Tools»(ref-235300-S01064053572006061900000) .
- Connect the charging station high and low pressure lines to the corresponding fittings on the J 39893 . See «Special Tools»(ref-235300-S01064053572006061900000) . The suction port (1) (low-side) of the compressor has a large internal opening. The discharge port (high-side) has a smaller internal opening into the compressor. The discharge port (2) (high-side) also has a deeper recess.
- Open the following controls on the charging station in order to allow refrigerant vapor to flow into the compressor: The low pressure control The high pressure control The refrigerant control
- Use the J 39400 in order to inspect for leaks at the following locations:. See «Special Tools»(ref-235300-S01064053572006061900000) . The pressure relief valve (5) The rear head switch location The compressor front head seal The compressor rear head seal The center cylinder seal The through bolt head gaskets The compressor shaft seal
- Turn OFF the low-pressure control and the high-pressure control on the charging station.
- Perform the following steps if an external leak exists: Perform the necessary corrective measures. Inspect the components for leaks again in order to verify that the leak is corrected.
- Recover the refrigerant.
- Disconnect both hoses from the J 39893 . See «Special Tools»(ref-235300-S01064053572006061900000) .
- Add 90 ml (3 fl oz) of new PAG lubricant to the compressor assembly.
- Slowly rotate the complete compressor assembly (excluding the crankshaft and the drive plate hub) several turns in order to distribute oil to all of the cylinder and the piston areas.
- Install a M9 x 1.25 threaded nut on the compressor crankshaft if the drive plate and clutch assembly are not installed.
- Use a box-end wrench or socket and handle in order to rotate the compressor crankshaft or clutch drive plate on the crankshaft several turns. Performing the above action will ensure piston assembly to cylinder wall lubrication.
- Using the J 39500-B , connect the J 39893 to the test plate high-side connector. See «Special Tools»(ref-235300-S01064053572006061900000) .
- Using the J 39500-B , connect the charging station low-pressure line to the low-pressure port of the J 39893 . See «Special Tools»(ref-235300-S01064053572006061900000) . Oil will drain out of the compressor suction port (1) if the compressor is positioned with the suction port downward.
- Attach the compressor to the J 34992 . See «Special Tools»(ref-235300-S01064053572006061900000) .
- Mount the compressor in a vise in order to place the compressor in a horizontal position.
- Use a wrench in order to rotate the compressor crankshaft or the drive plate hub ten complete revolutions at the speed of approximately one-revolution per second. Turning the compressor at less than one-revolution per second can result in a lower pump-up pressure. Low pump-up pressure may disqualify a good pumping compressor.
- Observe the reading on the high-pressure gauge at the completion of the tenth revolution of the compressor. The pressure reading for a good pumping compressor should measure 690 kPa (100 psi) or above. A pressure reading less than 620 kPa (90 psi) indicates one or more of the suction and/or discharge valves have an internal leak or an inoperative valve. Perform the following procedure if one of the valves are leaking or inoperative: Recover the refrigerant. Disassemble the compressor. Inspect the compressor for the cause of the leak. Repair the compressor as necessary. Reassemble the compressor. Repeat the pump-up test. Test for external leaks
- Recover the refrigerant from the high-side.
- Remove the J 39893 . See «Special Tools»(ref-235300-S01064053572006061900000) .
- Tilt the compressor with the compressor suction port (1) and the discharge port (2) positioned downward.
- Drain the PAG lubricant from the compressor. Allow the compressor to drain for 10 minutes.
- Refill the compressor with the proper amount of PAG lubricant. Pour the PAG lubricant into the suction port (1).
- If further assembly or processing is necessary, install a shipping plate or the J 39893 . See «Special Tools»(ref-235300-S01064053572006061900000) . The shipping plate or the J 39893 prevents the following materials from entering the compressor until the compressor is installed:. See «Special Tools»(ref-235300-S01064053572006061900000) . Air Dirt Moisture