Timing belt replacement: Opel Corsa B (12NZ, C12NZ, C14NZ, X12SZ, …)

🧭 Before you start

Disconnect intake, ignition, throttle and exhaust, remove the ancillary belt and timing covers, set TDC on cylinder one and lock the flywheel. Release the tensioner, remove the belt, camshaft cover, gearwheel and rear cover, then undo the head bolts and lift off the rocker shaft and head. Refit in reverse using the head bolt torque settings, and run the engine to check.

Fits: platform codes 1.2I, |, 1.4I

• Timing position: the crankshaft or camshaft is set and locked during this job

Don't miss

• Set the crankshaft to TDC for cylinder one and align the timing marks before the belt comes off.
• Lock the flywheel with the special tool so the crank cannot move.
• The alternator can be moved aside without disconnecting it.
• Follow the cylinder head torque settings from the adjustment data, not guesswork.
• As general practice, check head and block faces for flatness before fitting a new gasket.

Written for this job from the workshop steps below · TorqFix editorial.

🔧 Engine codes this applies to

📋 Procedure

1. Run the engine
2. Turn the engine off
3. Disconnect the battery
4. Refit all parts in the reverse order of removal
5. Cylinder head torque settings - Refer to 'Adjustment data/Torque settings'

6. Remove the air filter and the air inlet hose
7. Disconnect the distributor wiring
8. Disconnect the throttle cable
9. Disconnect the remaining wiring, cables and hoses
10. Disconnect the front exhaust pipe from the manifold
11. Remove the ancillary drive belt
12. Remove the alternator but do not disconnect
13. Remove the timing belt upper cover
14. Remove the timing belt lower cover
15. Turn the crankshaft to TDC for cylinder 1
16. Align the timing marks
17. Lock the flywheel
18. Use a special tool:
19. Alloy
20. Push the tensioner pulley away from the timing belt
21. Lock the tensioner
22. Remove the timing belt
23. Remove the camshaft cover
24. Remove the camshaft gearwheel
25. Remove the timing belt rear cover
26. Remove the cylinder head bolts
27. Remove the rocker shaft assembly
28. Remove the cylinder head

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