Chevrolet Cobalt Service & Repair Manual: Leak Test

Before beginning any leak test, attach a manifold gauge set and note pressure. If little or no pressure is indicated, a partial charge must be installed. Inspect all connections, compressor head gasket, oil filler plug and compressor shaft seal for leaks.

Electronic Leak Detectors

Current versions of electronic leak detectors have three settings, one for R-12, one for R-134a and one for gross. The gross setting is for isolating very large leaks already found in one of the other two settings. Refer to operating instructions for the unit being used and observe these general procedures.
1. Move detector probe one inch per second in areas of suspected leaks.
2. Position probe below test point, as refrigerant gas is heavier than air.
3. Inspect service access gauge port valve fittings, particularly when valve caps are missing, as dirt accumulations can destroy sealing area of valve core when manifold gauge set is attached. Replace missing valve caps after cleaning valve core area. Valve caps should only be finger tightened. Using pliers to tighten valve caps may distort sealing surface of valve.
4. Inspect for leaks in manifold gauge set and hoses, as well as rest of system.

Fluid Leak Detectors

Apply leak detector solution around joints to be tested. A cluster of bubbles will form immediately if there is a leak. A white foam that forms after a short while will indicate an extremely small leak. In some confined areas such as sections of the evaporator and condenser, use of an electronic leak detector is recommended.

Fluorescent Leak Detectors

The high density black light tool No. J2848-E, tracer dye injector tool No. J41436 and tracer dye tool No. J41447, or equivalents, were developed to detect refrigerant leaks on R-134a systems. Do not use any other tracer dye in these systems. Another type dye may cause premature compressor failure. Use only a 1/4 ounce charge of dye, larger amounts may effect system performance. After adding tracer dye, clean service valves and all affected surfaces of the dye with GM engine degreaser part No. 1050436, or equivalent, to prevent any false leak diagnosis.
    Flushing
    1. Remove expansion tube, if equipped. 2. Remove air compressor. 3. Install flush adapter to air compressor ...

    Oil Change
    Add the recommended refrigerant oil in the amount listed if you replace any of the parts listed. To avoid contamination, do not return the oil to the container once dispensed, and n ...

    See also:

    Chevrolet Cobalt Service & Repair Manual. Window Switch R&R
    Refer to Fig. 1 when performing following procedure. 1. Remove door panel pull cup trim plate. 2. Remove armrest pull cup. 3. Remove door lock switch and disconnect electrical connector. ...

    Chevrolet Cobalt Owners Manual

    Chevrolet Cobalt Service Manual


    Copyright © 2024 www.cheviguide.com - Chevrolet Auto Manuals - 0.0042