Variable Valve Timing Actuator: Service and Repair

Camshafts and camshaft adjuster, removing and installing
Special tools and workshop equipment required
^ Counterhold 3036
^ Chain tensioner holder 3366

Removing
^ Cylinder head installed
^ Lock carrier in service position
^ Remove toothed belt from camshaft sprocket.





^ Remove engine cover -arrows-.
^ Remove secondary air combination valve.





^ Unplug connector -arrow- at camshaft adjuster.
^ Remove cylinder head cover.
^ Loosen camshaft sprocket (counterhold with 3036).
^ Pull off cam shaft sprocket.
^ Remove entire Hall sensor.

Note: Excessive tightening of chain tensioner holder can damage camshaft adjuster.





^ Secure camshaft adjuster with chain tensioner holder 3366.





^ Re-check TDC position of camshafts:
^ Mark on the two camshafts must be in line with arrows on bearing caps.
^ Clean chain and camshaft sprockets opposite two arrows on bearing caps and mark installation position using colored markings.





^ The distance between the two arrows or between colored markings is 16 rollers on the drive chain.
^ The notch on exhaust camshaft is offset slightly toward inside in relation to chain roller -1-.

Note: Do not mark chain with a center punch or by making a notch, etc.





^ First remove bearing caps 3 and 5 on intake and exhaust camshafts.
^ Remove double bearing cap.
^ Remove both bearing caps on intake and exhaust camshaft chain sprockets.
^ Remove bolts securing camshaft adjuster.





^ Loosen bearing caps 2 and 4 of intake and exhaust camshafts alternately in diagonal sequence and remove.
^ Remove intake and exhaust camshafts together with camshaft adjuster.

Installing





^ Replace rubber/metal gasket for camshaft adjuster and apply a thin coat of sealant "AMV 188 001 02" to shaded areas.
^ Install drive chain on camshaft sprockets as follows:





^ If old chain is re-installed, install chain so that colored markings are in line-arrows-.





^ If new chain is installed, distance between notches -A- and -B- on camshafts must be 16 rollers on chain. Illustration shows exact positions of 1st and 16th rollers on sprockets.
^ The notch -A- is offset slightly toward inside in relation to chain roller -1 -
^ Insert camshaft adjuster between drive chain (2 mechanics needed).
^ Locate camshafts together with drive chain and camshaft adjuster in cylinder head.
^ Oil running surfaces of both camshafts.

Notes:
^ Dowel sleeves for bearing caps and camshaft adjuster must be installed in cylinder head.
^ When installing bearing caps ensure that identification mark is readable from intake side of cylinder head.

^ Tighten mountings of camshaft adjuster (watch position of dowel sleeves).





^ Tighten bearing caps 2 and 4 of intake and exhaust camshafts alternately in diagonal sequence (watch position of dowel sleeves).
^ Install both bearing caps on intake and exhaust camshaft chain sprockets.
^ Check correct setting of camshafts:





^ The two markings on camshafts must be in line with the two arrows on bearing caps -arrows-.





^ The distance between the two arrows on bearing caps or between colored markings is 16 rollers on the drive chain.
^ The notch on exhaust camshaft is offset slightly toward inside in relation to chain roller -1
^ Remove chain tensioner holder 3366.





^ Apply thin coat of sealant "AMV 188 001 02" to shaded area on double bearing cap and install bearing cap (watch position of dowel sleeves).
^ Install remaining bearing caps (watch position of dowel sleeves).
^ Replace oil seals for intake and exhaust camshafts.





^ Install camshaft sprocket.

Note installation position:
Narrow web of camshaft sprocket must face outward -arrows- and marking for TDC No. 1 cylinder must be visible from front.
^ Install securing bolt for camshaft sprocket (use counterhold 3036).
^ Install Hall sensor.
^ Install cylinder head cover.





^ Align marking on camshaft sprocket with marking on cylinder head cover.
^ Align marking on vibration damper with marking on bottom section of toothed belt guard.

Note: The crankshaft must not be at TDC when camshaft is turned. Otherwise there is a risk of damage to valves and piston crowns.

^ Install toothed belt (adjust valve timing).
^ After installing camshafts, engine must not be started for approximately 30 minutes. Hydraulic valve compensation elements have to settle (otherwise valves will strike pistons).
^ After working on valve gear, turn engine carefully at least 2 rotations to ensure that none of the valves make contact when starter is operated.





Tightening torques