A/C - Refrigerant Loss Prevention

91chevy22

GMC NUMBER: 91-1B-112(A)

GROUP: 1B Air Conditioning


DATE: September, 1991


CORPORATE NUMBER: 971202R


SUBJECT: A/C REFRIGERANT LOSS DUE TO LOOSE OR MISSING ACCESS FITTING CAPS

MODELS: 1980-91 TRUCKS WITH A/C

THIS BULLETIN CANCELS AND REPLACES GMC TRUCK BULLETIN 91-1B-112 DATED JULY 1991. ALL COPIES OF 91-1B-112 SHOULD BE DISCARDED.


This bulletin is being revised to add 1990-91 model years and to update a discontinued part number for high side valve-cap and seal.

All GM 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.

Figure 1:

When servicing any vehicle's A/C system, make sure all access fitting cap seals (refer to Figure 1) are in place and tight. 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 Valve - Cap and Seal
P/N 52451233 PIN 6551640

Parts are currently available from GMSPO.