TorqFix

W204/W212 - 651 engine - ancillary drive belt — MERCEDES-BENZ

W204/W212 - 651 engine - ancillary drive belt on Mercedes-Benz: 17 steps, engines 651.911, 651.912, 651.913, 651.924.

Workshop procedure for MERCEDES-BENZ — the exact step sequence and torque figures, straight from real workshop data.

17 steps 5 engine codes

🧭 Before you start

Fits: platform codes 180, CDI, BLUEEFF, -T, |, 200, 220, -COUPE, 250, 4MATIC, -4MATIC, 300, HYBRID

  • Timing position: the crankshaft or camshaft is set and locked during this job
  • Special tools named: locking pin

🔧 Engine codes this applies to

651.911651.912651.913651.924651.925

📋 Procedure

  1. Remove the air filter air inlet
  2. Turn the tensioner anti-clockwise
  3. Remove the ancillary drive belt bracket
  4. Note: Release the tensioner slowly
  5. Note: In an anti-clockwise direction
651.911? Steps differ between engine variants — check this job against your exact car before you commit to it. Check my car — free →
  1. Lock the tensioner; use a locking pin
  2. Remove the ancillary drive belt
  3. Refit the air filter air inlet
  4. Start the engine
  5. Check for correct operation

Other MERCEDES-BENZ procedures

Who makes these pages, and how

TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.

The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.

Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.

Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com

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Workshop data on this page last updated 20 Sep 2026.