A/C - Lack of Heating Performance
87buick13Bulletin: 88-1-2
Date: Dec., '87
Ref. No.: 88-028-1
Corp. Ref. No.: 801101
SUBJECT: POOR HEATER PERFORMANCE
MODELS AFFECTED: 1985 THRU 1988 ELECTRA/PARK AVENUE WITH C68 AIR CONDITIONING (AUTOMATIC) 1986 THRU 1988 LESABRE WITH C68 AIR CONDITIONING (AUTOMATIC)
In the event of low heat in any of the above cars, check the following:
^ Proper coolant level
^ Proper coolant fill procedure
^ Proper movement and position of slave door
If all of the above operations have been checked and heat is still insufficient, perform the following:
1. Remove the heater evaporator case cover to gain access to the heater core.
2. Inspect the alignment of the heater core to the case. Be sure the core is properly sealed to the case. The C68 automatics use a copper brass core different from the C60 manuals, which use an aluminum core with plastic in/out tubes. It is possible in manufacturing to improperly install the C68 copper brass core in the case; thus allowing cold air to bypass the core (See Illustration 1), and blend in with the hot air from the core before entering the passenger compartment.
3. Reposition core, retainer and seals as necessary.