Removal and Replacement

Camshafts, removing and installing
(with cylinder head installed)





Special tools, testers and auxiliary items required
^ Retainer 3036
^ Chain tensioner retainer 3366
^ Torque wrench V.A.G 1331
^ Torque wrench V.A.G 1332
^ Sealant AMV 174 004 01
^ Sealant D 454 300 A2

Removing
- Remove engine cover.
- Remove upper toothed belt guard.





- Bring camshaft gear to marking for TDC cylinder 1 by turning crankshaft. Marking on camshaft gear must be flush with marking on cylinder head cover.
- Remove cylinder head cover.
- Remove toothed belt from camshaft gear.
- Turn crankshaft back slightly.
- Remove camshaft sprocket. To loosen bolt, counterhold camshaft gear using retainer 3036.
- Remove Hall sensor housing.
- Remove washer and cover for Hall sensor.





- Clean drive chain and camshaft chain sprockets - arrows - across from both on bearing caps and mark installed position with a color marking.

Note:
^ Do not mark chain using a center punch or similar means!
^ The distance between both - arrows - or colored markings consists of 16 rollers of the drive chain.





- Secure camshaft adjuster or chain tensioner using Bracket for Chain Adjustment 3366.

Note: Hydraulic chain tensioner can be damaged if Bracket for Chain Adjustment 3366 is tightened too hard.





- First remove bearing caps 3 and 5 from intake and exhaust camshafts.
- Remove double bearing cap.
- Remove both bearing caps from chain sprocket on intake and exhaust camshafts.
- Remove securing bolts of camshaft adjuster/chain tensioner.
- Alternating in diagonal sequence, loosen bearing caps 2 and 4 of intake and exhaust camshafts and remove.
- Remove intake and exhaust camshafts with camshaft adjuster or chain tensioner and Bracket for Chain Adjustment 3366.

Installing

Note:
^ When installing the camshafts, the cam lobes for cylinder 1 must point upward.
^ When installing bearing caps, verify marking on cap is readable from intake side of cylinder head.

- Place drive chain onto both camshaft sprockets according to color markings.





Note:
^ When using a new drive chain, distance between notches - A - and - B - must be 16 rollers on the chain.
^ Illustration shows where first and sixteenth drive chain rollers must be installed on chain gears.
^ Notch - A - is slightly offset inward toward chain roller - 1 -





- Replace rubber/metal seal for camshaft adjuster or chain tensioner and coat hatched surface with thin coat of sealant D 454 300 A2.
- Insert camshaft adjuster/chain tensioner between drive chain.
- Oil running surfaces of both camshafts.
- Insert camshafts with drive chain and camshaft adjuster/chain tensioner into cylinder head.
- Tighten camshaft adjuster/chain tensioner to 10 Nm (pay attention to bushing).





- Alternating in diagonal sequence, tighten bearing caps 2 and 4 of intake and exhaust camshafts and tighten to 10 Nm (pay attention to bushing).





- Install both bearing caps on chain gears of intake and exhaust camshafts. Check camshaft for proper adjustment and tighten bearing cap to 10 Nm (pay attention to alignment bushing).
- Remove chain tensioner retainer 3366.





- Coat hatched surface of double bearing cap lightly using sealant AMV 174 004 01, install and tighten to 10 Nm (pay attention to bushing).
- Install remaining bearing cap and tighten to 10 Nm (pay attention to alignment bushing).





- Install camshaft gear (thin rib toward outside and TDC marking visible) and tighten bolt to 65 Nm (use Retainer 3036).





- Check position of camshafts - arrows - to each other again.

The rest of assembly is basically a reverse of disassembling.

Install toothed belt and adjust valve timing.

Note: After installing new valve lifters, the engine may not be started for approx. 30 minutes. The hydraulic equalization elements must seat themselves (otherwise the valves will crash into the pistons).