INADEQUATE HEAT FROM HEATER REPOSITION HEATER CORE

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.

Illustration 1:

1 - SLAVE DOOR

2 - HEATER CORE

3 - EVAPORATOR

4 - TEMPERATURE VALVE

5 - IMPROPER HEATER LORE POSITION

6 - HEATER CLAMP

7 - "LEAK" /AIR BYPASS

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.