AIR CONDITION ORIFICE TUBE LOCATION CHANGE

VEHICLES AFFECTED: 1987 "H" AND "C" MODELS

On 1987 "H" and 'C" models the air conditioning orifice tube was moved from the inlet of the evaporator (1986 models) to a point midway between the evaporator and condensor (Figure 1). The orifice tube was relocated to eliminate the hissing sound which was objectionable to some owners.

Some technicians have not been aware of this relocation and have installed another orifice tube back at the evaporator. This obviously will severely reduce cooling. To check for the presence of the orifice tube, feel the liquid line between the orifice tube and the evaporator; it should be cold when the air conditioning is in operation.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.