Camshaft: Service and Repair
Camshaft
Special tools, testers and auxiliary items required
• Diesel Injection Pump Locking Pin (3359)
• Camshaft Gear Counter Holder (T10051)
• Puller (T10052)
• Camshaft Fitting Tool (T40094)
• Camshaft Fitting Tool (T40095)
• Camshaft Fitting Tool (T40096)
• Torque Wrench (5-50 Nm) (V.A.G 1331)
• Torque Wrench (40-200 Nm) (V.A.G 1332)
• Silicone Adhesive Sealant (D 176 501 A1)
Removing
- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.
- Remove the fuel filter.
- Remove the auxiliary fuel pump/fuel pump 2.
- Remove the toothed belt from the camshaft and high pressure pump gears. Refer to => [ Toothed Belt ] Toothed Belt.
- Remove the cylinder head cover. Refer to => [ Cylinder Head Cover ] Cylinder Head Cover.
- Remove the bolts - 1 - for the camshaft gear.
- Remove the camshaft gear from the hub.
- Counter hold the hub using the camshaft gear counter-holder (T10051) and loosen the hub bolt - 1 -.
- Unscrew the hub bolt approximately 2 turns.
- Install the puller (T10052) and align it to the bores in the hub.
- Tighten the bolts - 1 -.
- Tighten the puller - 2 - evenly to tension the hub until the hub loosens from the camshaft.
• Hold the valve stem removal tool with a 30 mm wrench.
- Remove the hub from the camshaft.
- Remove the vacuum pump. Refer to => [ Vacuum Pump ] Service and Repair.
- Remove the bearing frame bolts/nuts in sequence - 24 through 1 -.
- Remove the bearing frame.
- Carefully remove the camshafts.
Installing
• Seal the surfaces between the bearing frame and the cylinder head with silicone adhesive sealant (D 176 501 A1).
The camshafts may only be installed using the camshaft fitting tool (T40094) as described. Otherwise the axial bearings inside the bearing frame will get permanently damaged and it will be necessary to replace the cylinder head.
- Remove any sealant still on the cylinder head and on the bearing frame with a rotating plastic brush.
Make sure that no sealant residue enters the cylinder head and bearings.
- Clean the sealing surfaces, they must be free of oil and grease.
- Oil the journal surfaces of the camshafts.
Assemble the camshaft fitting tool (T40094) as follows:
- Remove the mounts (T40094/3) , (T40094/4) and (T40094/5) from the base plate. Loosen the threaded connections from below.
• If the camshaft fitting tool (T40094) mounts are not marked, mark the removed mounts, for example, with numbers, to assure it can be assembled later.
- Instead, mount the mounts (T40094/9) and (T40094/10) in the empty outer locations.
- Position the (T40094/2) on "A" and (T40094/1) on "F".
- First, install the intake camshaft as illustrated. Make sure the indentation - arrow - for the cylinder head bolt faces "outward".
- Install a 0.55 mm feeler gauge and push the mount (T40094/8) into the groove in the intake camshaft.
- Install the exhaust camshaft and lock it by the groove - arrow - using the cover (T40094/11).
- Mount the component of T40096 (T40096/1) on the toothed gears of the exhaust camshaft.
Make sure the clamping jaw marked with an arrow is on the wider sprocket.
- Tighten the component of T40096 (T40096/1) with the thumb wheel until the tooth faces align. Use a 13 mm open end wrench if necessary.
- Slide the exhaust camshaft toward the intake camshaft until the splines mesh.
- Position the bearing frame on the camshafts.
• All the camshaft bearings must lie on the camshafts.
- Position the camshaft fitting tool (T40095) as illustrated and secure the camshafts in the bearing frame.
- Remove the cover (T40094/11).
- Remove the mount (T40094/8) from the groove in the intake camshaft.
- Cut the sealant tube nozzle at the front mark (nozzle diameter: approximately 2 mm).
- Apply a bead of sealant (approximately 2 to 3 mm thick) - arrow - on the sealing surfaces of the cylinder head as illustrated.
Excess sealant could get on the camshaft bearings or seal off the oil supply holes.
• Do not apply the sealant bead thicker than indicated.
• Make sure that the excess sealant does not seal off the oil supply holes - arrow - for the bearing frame.
Sealant Bead for the Bearing Frame
- Remove the camshafts with the bearing frame and the camshaft fitting tool (T40095) from the camshaft fitting tool (T40094).
- Carefully install the camshafts and bearing frame on the cylinder head.
- First, tighten the bearing frame bolts/nuts hand tight in sequence - 1 through 24 -.
• The bearing frame must be touching the entire contact surface of the cylinder head.
- Fasten the bearing frame bolts/nuts in sequence - 1 through 24 - until they stop. Tightening specification: 10 Nm
- Remove the camshaft fitting tool (T40095) and component of T40096 (T40096/1).
- Replace the camshaft seal. Refer to => [ Camshaft Seal ] Service and Repair.
- Drive a new sealing cap (- item 15 - in the => [ Valvetrain Overview ] Service and Repair) into the cylinder head with a suitable drift until it is flush.
Further installation is performed in the reverse order of removal, noting the following:
Risk of damaging valves and piston heads after working on the valvetrain.
• The engine must not be started for about 30 minutes after installing the camshafts because the hydraulic lash adjusters must seat themselves.
• To ensure the valves do not strike the pistons when starting, carefully rotate the crankshaft at least 2 revolutions.
- Place the hub onto the camshaft.
- Tighten the bolt - 1 - for the hub to 100 Nm. To do this, use the camshaft gear counter-holder (T10051).
- Push the camshaft gear onto the hub.
• The toothed segment - arrow - of the camshaft gear must face upward.
- Install the bolts - 1 - for the camshaft gear by hand to eliminate play.
- Lock the hub using the diesel injection pump locking pin (3359).
- Install the toothed belt and adjust the valve timing. Refer to => [ Toothed Belt ] Toothed Belt.
- Install the vacuum pump. Refer to => [ Vacuum Pump ] Service and Repair.
- Install the cylinder head cover. Refer to => [ Cylinder Head Cover ] Cylinder Head Cover.
- Install the fuel filter.
- Install the auxiliary fuel pump/fuel pump 2.