11 31 051 Replacing timing chain

Special tools required: 

• 11 2 000
• 11 8 250
• 11 8 300
• 11 8 370

Necessary preliminary tasks: 

• Unscrew all spark plugs. Refer to 12 12 011 REPLACING ALL SPARK PLUGS .
• Remove cylinder head cover. Refer to 11 12 000 Removing and installing, sealing cylinder head cover (COOPER S)  .
• Remove pulse generator on camshaft. Refer to 12 14 537 REPLACING CAMSHAFT PULSE GENERATOR .
• Remove hydraulic chain tensioner. Refer to 11 31 091 Removing and installing/replacing hydraulic chain tensioner (COOPER S)  .
• Remove timing chain cover. Refer to 11 14 122 Removing and installing, sealing / replacing timing case cover (COOPER S)  .
• Remove left engine mounting. Refer to 22 11 001 REPLACING RIGHT ENGINE MOUNT .

Fit special tool 11 8 370 on cylinder block (1) and engine mounting (2).

Fig 1: Fitting Special Tool On Cylinder Block

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Release camshaft retaining bolt (1) and hold camshaft gear with special tool 11 8 250.

Fig 2: Releasing Camshaft Retaining Bolt

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Unscrew plugs (2).

Unscrew retaining bolt for camshaft gear, then remove gear wheel and chain.

Fig 3: Removing Gear Wheel & Chain

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Remove camshaft gear from timing chain.

Unscrew retaining bolts (1) of chain guides and remove both guides (2).

Installation note: 

If the timing chain is replaced, the camshaft gear and crankshaft gear must also be replaced.

Remove crankshaft gear using special tool 11 8 300 together with 11 2 000.

Fig 4: Removing Crankshaft Gear

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Installation note: 

Shrink-fit crankshaft gear (1) onto crankshaft.

Fig 5: Fitting Crankshaft Gear Onto Crankshaft

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Check correct position of locating pin (2).

Use a hotplate to heat crankshaft gear to a maximum temperature of 150°C. 

Install timing chain.

Fig 6: Installing Retaining Screws Of Chain Guides

Courtesy of BMW OF NORTH AMERICA, INC.

Install clamping rail and guide rail (2).

Install retaining screws (1) of chain guides.

Tightening torque: 11 12 12AZ. Refer to ENGINE - TIGHTENING TORQUES .

Place timing chain on camshaft gear.

Fit camshaft gear onto camshaft.

Fit central bolt for camshaft gear.

Tightening torque 11 12 5AZ. Refer to ENGINE - TIGHTENING TORQUES .

Installation note: 

Triangular adjustment mark (1) on camshaft gear must be aligned with copper -colored timing chain links (2).

Fig 7: Identifying Triangular Adjustment Mark

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Installation note: 

The two triangular adjustment marks (1) on crankshaft gear must be aligned with copper -colored timing chain links (2).

Fig 8: Aligning Adjustment Marks On Crankshaft Gear

Courtesy of BMW OF NORTH AMERICA, INC.

1. Camshaft adjustment mark lines up with colored chain link.
2. Camshaft gear.
3. Left timing chain guide.
4. Right timing chain guide.
5. Tensioning device for timing chain.
6. Crankshaft gear.
7. Chain.
8. Crankshaft adjustment mark lines up with the two colored chain links.
Fig 9: Identifying Camshaft Adjustment Components
Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.