Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
12 31... Replacing alternator belt pulley
- 12 7 110
Remove and install alternator drive belt.
Depending on alternator type, grip shaft with:
- hexagon socket
- multi-tooth socket or
- Torx socket wrench
Release nut with special tool 12 7 110.
Installation:
For tightening torque refer to 2AZ / 3AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .
Procedure with special tool 12 7 121:
Illustration shows N42 engine
If fitted, remove cover cap from belt pulley.
Depending on alternator type, slacken screw with:
- Torx key
- Hold inner multi-wrench tool (special tool 12 7 122).
Release freewheel with special tool 12 7 121 and remove.
Installation note:
For tightening torque refer to 8AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .
Procedure with special tool 12 7 123:
Depending on alternator type, slacken screw with:
- Torx key
- Hold inner multi-wrench tool (special tool 12 7 122).
Release freewheel with special tool 12 7 123 and a ring spanner and remove.
Installation note:
For tightening torque refer to 8AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.