MANUAL UPDATE- A/C COMPRESSOR AND EVAP. TUBE/HOSE ROUTINGS

Model and Year: 1989 CORVETTE

The following supersedes information previously published in the 1989 Corvette Service Manual Section lBl, Pages 27 to 29, "Manually Controlled Air Conditioning, Cycling Clutch (Orifice) Tube CCOT type.

The flange joining the air conditioning compressor hose and evaporator tube to the condenser has been eliminated. The compressor hose and evaporator tube fittings are now separate connections to the condenser. The following steps detail new air conditioning compressor hose and evaporator tube removal and installation procedures.

IMPORTANT: The opposing fitting should always be backed up with a wrench to prevent distortion of connecting lines or components, when tightening flexible hose connections.

COMPRESSOR HOSE AND O-RING SEAL

Figure 1

Remove or Disconnect

1. Discharge air conditioning system. 2. Hose and 0-ring from accumulator. 3. Hose and 0-ring from condenser. 4. Hose and 0-rings from compressor.

Install or Connect

IMPORTANT: Coat new 0-rings with clean 525 refrigerant oil prior to assembly.

1. Hose and new 0-rings to compressor.

Tighten

- Compressor hose bolt to 33 N.m (24 lbs. ft.).

2. Hose and new 0-ring on condenser.

Tighten

- Condenser hose fitting nut to 23 N.m (17 lbs. ft.).

3. Hose and new 0-ring on accumulator.

Tighten

- Compressor hose fitting to 40 N.m (30 lbs. ft.).

4. Evacuate and charge air conditioning system.

AIR CONDITIONING EVAPORATOR TUBE

Figure I

Remove or Disconnect

1. Discharge air conditioning system

2. Air conditioning compressor pressure cycling switch.

3. Air conditioning engine coolant temperature switch.

4. Hose and 0-ring from evaporator core.

5. Hose and 0-ring from condenser.

Install or Connect

IMPORTANT: Coat all new 0-rings with clean 525 refrigerant oil prior to assembly.

1. Evaporator tube and new 0-rings to condenser.

Tighten

- Evaporator tube fitting to 16 N.m (30 lbs. ft.).

2. Evaporator tube and new o-rings to evaporator core.

Tighten

- Evaporator tube fitting to 40 N.m (30 lbs. ft.).

3. Air conditioning compressor engine coolant temperature switch.

Tighten

- Air conditioning compressor engine coolant temperature switch to 2 N.m (18 lbs. in.).

4. Air conditioning compressor pressure cutoff switch to 2 N.m (18 lbs. in.).

5. Evacuate and charge air conditioning system.

TORQUE SPECIFICATIONS

Compressor Hose bolt to Compressor 33N.m (24 lbs. ft.)

Compressor Hose Fitting to Condenser 23N.m (17 lbs. ft.)

Compressor Hose Fitting to Accumulator 40N.m (30 lbs. ft.)

Evaporator Tube Fitting to Condenser 16N.m (12 lbs. ft.)

Evaporator Tube Fitting to Evaporator Core 40N.m (30 lbs. ft.)

Air Conditioning Engine Coolant 2 N.m (18 lbs.in.) Temperature Switch

Air Conditioning Compressor Pressure Cycling Switch 2 N.m (18 lbs. in.)

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.