Camshaft: Service and Repair

Camshafts

Special tools, testers and auxiliary items required

• Puller (T40001)

• Retainer (3036)

Removing

• Sealing surfaces on guide frame at bottom and on cylinder head at top must not be worked.

• Camshaft bearings are integrated in cylinder head or in guide frame. Before removing guide frame, tension on toothed belt must be released.

• If guide frame was loosened, camshaft sealing ring and sealing cap must be replaced.

- Remove the cylinder head cover. Refer to => [ Cylinder Head Cover ] Service and Repair.

- Remove camshaft adjuster. Refer to => [ Camshaft Adjuster ] Camshaft Adjuster.

- Remove toothed belt. Refer to => [ Toothed Belt, without Divided Toothed Belt Guard ] Toothed Belt, without Divided Toothed Belt Guard.

- Loosen camshaft gear with the (3036).






- Pull off camshaft gear using the (T40001) , (T40001/6) and (T40001/7).






- Remove toothed belt guard at rear of cylinder head.

- Remove guide frame bolts in sequence - 6 through 1 - and carefully remove guide frame.






- Remove camshafts together with drive chain from cylinder head.

Installing

• For the correct tightening specifications, refer to => [ Valvetrain Overview ] Valvetrain Overview

• For the correct tightening specifications, refer to => [ Cylinder Head Assembly Overview ] Cylinder Head Assembly Overview

• Sealing surfaces must be completely free of oil and grease.

• The pistons must not be positioned at TDC.

• Make sure that all roller cam followers make contact correctly on valve stem ends.

- Remove the old sealant from the guide frame groove and from sealing surfaces.






- Prevent dirt and adhesive residue from entering cylinder head.

- Oil journal surfaces of camshafts.

- Place the drive chain onto the removed camshaft chain sprockets as follows:

- Oil journal surfaces of camshafts.

• Cams - A - of cylinder 4 must face each other.






• The notches - arrows - on both camshafts must align.

• The side surfaces of the notches must be exactly vertical.

- Place camshafts together with drive chain in cylinder head and in chain tensioner.

- Verify TDC position of camshafts again.

• Cams - A - of cylinder 4 must face each other.






• The notches - arrows - on both camshafts must align.

• The side surfaces of the notches must be exactly perpendicular to the cylinder head.

- Oil journal surfaces of camshafts.

- Apply an even, light sealant bead into the clean groove of the guide frame.






Sealant, refer to the electronic parts catalog ETKA.

• Sealant must not be applied too thickly.

• Attaching and bolting the guide frame should be performed without interruption because the sealant begins to harden immediately as soon as it contacts the sealing surfaces.

• Note the expiration date of the sealing compound.

- Set the guide frame in place so that it can get by the EGR vacuum regulator solenoid valve (N18) - arrow -.






- Replace guide frame bolts.

• The placement of the camshafts must be exact within the axial bearings of the guide frame.

- Tighten bolts in several stages in tightening sequence. Refer to => [ Guide Frame Tightening Sequence ] Valvetrain Overview.






• Ensure guide frame is not tilted.

- Then check TDC position of camshafts by inserting the (T10252) as far as stop.






• Rotate camshafts back and forth slightly if necessary to insert the (T10252).

• Ignore - arrows -.

- If the (T10252) cannot be inserted, remove guide frame again and repeat camshaft installation.

- Remove the (T10252).

- Drive in the sealing cap => [ (Item 25) Sealing Cap ] Valvetrain Overview with the thrust piece (3334) approximately 1 to 2 mm deep.

- Install camshaft sealing ring. Refer to => [ Exhaust Camshaft Seal ] Service and Repair.

- Install the rear toothed belt guard.

- Insert fitting key into camshaft.

- Install the camshaft sprocket. Hold the camshaft sprocket with the (3036) and tighten the bolt






• When turning camshaft, pistons may not be at TDC for any cylinder. Valves/pistons may be damaged.

• Be sure fitting keys are properly seated.

- Install toothed belt. Refer to => [ Toothed Belt, without Divided Toothed Belt Guard ] Toothed Belt, without Divided Toothed Belt Guard.

- Install camshaft adjuster. Refer to => [ Camshaft Adjuster ] Camshaft Adjuster.

- Install cylinder head cover. Refer to => [ Cylinder Head Cover ] Service and Repair.

Assemble in reverse order of disassembly.