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 (with overrunning clutch)
2009 BMW 335dSECTION 12 31... Replacing alternator belt pulley (with overrunning clutch)
Special tools required
- 12 7 120
Remove and install alternator drive belt.
Grip alternator shaft with:
- internal serration
Release nut with special tools 12 7 120.
Installation:
RENDER: 1.0x
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.