K Tahoe 4WD V8-4.8L VIN V (2000)
Service Port HVAC: Testing and Inspection
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:
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The evaporator inlet and outlet
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The accumulator inlet and outlet
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The condenser inlet and outlet
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All of the brazed and welded areas
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The areas showing signs of damage
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The hose couplings
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The compressor rear head
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The housing joints
Service Ports/Access Valves
The primary seal for the service ports is the sealing cap. This cap contains a specially designed O-ring seal or gasket that provides a leak-free seal. A
loose or missing cap, or using the wrong cap, results in the loss of the refrigerant charge.
Evaporator Core
Finding leaks in the evaporator core is very difficult. In order to leak test the core, complete the following steps:
1. Turn the blower fan to the HI position for 15 seconds or longer.
Then, turn the blower fan to the OFF position.
2. Wait 10 minutes.
3. Remove the passenger compartment air filter.
4. Insert the probe of the leak detector as close to the evaporator as possible.
A solid alarm indicates the discovery of a leak.
5. If possible, visually inspect the core face for evidence of refrigerant oil. Use a flashlight.
Compressor Block Fitting and Shaft Seal
Complete the following steps:
1. Blow shop air behind and in front of the compressor clutch/puller for at least 15 seconds.
2. Wait 1-2 minutes.
3. Probe the area in front of the pulley.
A solid alarm indicates the discovery of a leak.
