This bulletin is being revised to include 1991 model years and to update a discontinued part number for high side valve cap and seal.
1985-1991 DeVilles and Fleetwoods, 1982-1991 RWD DeVilles and Broughams, 1986-1991 Eldorados and Sevilles, 1982-1988 Cimarrons, and 1987-1991 Allantes air conditioning High Side and Low Side access fittings are supplied with a BLACK PLASTIC CAP AND SEAL ASSEMBLY WHICH PROVIDES THE PRIMARY REFRIGERANT SEAL for the service fittings.
If the cap and seal assembly is missing or loose, a significant amount of refrigerant may leak through the valve core located in the access fitting which could result in poor A/C performance or failure. WHEN SERVICING ANY VEHICLE'S A/C SYSTEM, MAKE SURE ALL ACCESS FITTING CAP SEALS ARE IN PLACE AND TIGHT. Refer to Figure 1. Caps should be threaded on until contact with the O-ring seal is made and then tightened another 1/4-1/2 turn to ensure proper sealing.
High Side Low Side Valve-Cap and Seal (3/8 x 24) Valve-Cap and Seal (7/16 x 20) P/N 52451233 P/N 6551640
Parts are currently available from GMSPO.
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.