1. Disconnect the negative battery cable.
2. Discharge the refrigerant from the system. (See RECOVERY.) (See CHARGING.)
Caution
3. Disconnect the cooler hose (Lo) (L.H.D) or cooler pipe No.4 (R.H.D.) and cooler pipe No.3. (See REFRIGERANT LINES REMOVAL/INSTALLATION.)
4. Remove the dashboard. (See DASHBOARD REMOVAL/INSTALLATION.)
5. Remove the duct (1).
6. Remove the air mix actuator. (Full-auto air conditioner)
7. Remove the screws and cover.
8. Remove the one plate (L.H.D.) or two plates (R.H.D.).
9. Remove the bolts and shift the outlet pipe. Do not allow compressor oil to spill.
10. Remove the expansion valve. Do not allow compressor oil to spill.

11. Install in the reverse order of removal.

12. Perform the refrigerant system performance test. (See REFRIGERANT SYSTEM PERFORMANCE TEST.)
A/c unit disassembly/assembly
Evaporator inspectionMazda 6 Service Manual: Rocking the Vehicle
WARNING
Do not spin the wheels at more than 56 km/h (35 mph), and do not allow
anyone to stand behind a wheel when pushing the vehicle: When the vehicle
is stuck, spinning the wheels at high speed is dangerous. The spinning tire could
overheat and explode. This could cause serious injuries.
...
Mazda 6 Service Manual: Timing chain
TIMING CHAIN REMOVAL/INSTALLATION
Warning
Fuel vapor is hazardous. It can very easily ignite, causing
serious injury and damage. Always keep sparks and flames away from fuel.
Fuel line spills and leakage are dangerous. Fuel can ignite and
cause serious injures or death and damage. Fuel ...