Variable Valve Timing Actuator: Service and Repair
Remove complete air guide for alternator.
Remove fan using special tools 11 5 030 and 11 5 040.
CAUTION! Left-hand threads.
Hold belt pulley in position using special tool 11 5 030 and unscrew union nut on water pump.
Removing fan and fan coupling from water pump and removing together with fan shroud.
Installation:
Tighten fan with special tool 11 5 040.
Tightening torque = 40 Nm
NOTE: 40 Nm tightening torque is equal to 30 Nm on scale of torque wrench.
Removing cylinder head cover.
Removing spark plugs.
REMOVAL:
Removal of VANOS adjustment unit is described separately from installation. Assembly sequence for removal and installation is different.
Unscrew oil pressure pipe.
Disconnect solenoid-valve plug-in connection.
Unscrew suspension eye.
Remove cable channel.
Pull off plastic cover for intake camshaft.
Rotate engine engine-wise until cam tips on intake and exhaust camshafts on 1st cylinder face one another.
Pull dust guard out of the special tool bore.
Secure crankshaft in TDC position with special tool 11 2 300.
CAUTION! Removing special tool 11 2 300 before starting engine.
Unscrew studs.
Locate camshafts with special tool 11 3 240.
Unfasten screw plugs.
Unfasten sprocket screws on exhaust camshaft.
Press chain tensioner down from above and lock with special tool 11 3 290.
Unscrew nuts.
Version with plate spring
Fit special tool 11 5 490 to exhaust camshaft gear. Using special tool 11 5 490, rotate sprockets and secondary chain clock-wise, at the same time removing the VANOS adjustment unit.
Version without plate spring
NOTE: On the version without plate spring, the VANOS adjustment unit can be removed without special tools.
Remove VANOS adjustment unit.
Installation:
Installation of VANOS adjustment unit is described separately from removal. Assembly sequence differs between removal and installation.
Version with plate spring
Rotate sprockets and secondary chain clockwise with special tool 11 5 490 until detent position is reached.
Version without plate spring
NOTE: On version without plate spring, special tool is not required.
Turn sprockets with mounted secondary chain clockwise as far as stop.
Press back spline shaft on adjustment unit (1) as far as detent in housing (2).
Note dowel sleeves (1).
Coat edges of joint between cylinder head and VANOS adjustment unit with Drei Bond 1209 sealing agent (refer to BMW Parts Service).
Replace seal.
Fit VANOS adjustment unit.
Rotate spline shaft (1) until internal spline engages.
Version with plate spring
Fit special tool 11 5 490 to exhaust camshaft. Rotate chain and gears with special tool 11 5 490 counter-clockwise until spline shaft engages in internal spline of sprocket (2).
CAUTION! Always ensure that the FIRST suitable tooth engages.
Version with plate spring
Slide VANOS adjustment unit towards cylinder head. Guiding the helical bevel splined shaft into the helical bevel splined sprocket turns the sprockets with mounted chain counterclockwise.
Rotate chain and gears with special tool 11 5 490 counter-clockwise.
Version without plate spring
Rotate chain and gears by hand counter-enginewise until spline shaft locates in internal spline of sprocket (2).
CAUTION! Always ensure that the FIRST suitable tooth engages.
Version without plate spring
Slide VANOS adjustment unit towards cylinder head. Guiding the helical bevel splined shaft into the helical bevel splined sprocket turns the sprockets with mounted chain counterclockwise.
Guide the chain with sprockets in counterclockwise direction by hand.
Tighten down VANOS adjustment unit.
Removing special tool 11 3 290.
CAUTION! Strong spring force.
Unfasten screw connection (3).
Remove spring (2) and piston (1).
Install special tool 11 3 390 in chain tensioning sleeve (1).
Fit adjusting screw to tensioning rail.
Preload tensioning rail with special tool 11 3 390 by rotating the adjusting screw with special tool 00 9 250 or standard torque wrench to 1.3 Nm.
Tighten sprocket on exhaust camshaft in two passes.
Tightening torque:
Application torque = 5 Nm
Jointing torque = 22 Nm
Remove special tool 11 3 240.
Remove special tool 11 2 300.
NOTE: If work was carried out on the camshafts previously, rotate engine twice engine-wise, then check camshaft setting.
Secure crankshaft with special tool 11 2 300 in TDC position of 1st cylinder.
CAUTION! Do not turn the engine back.
Remove special tool 11 2 300 before switching on the engine.
Fit special tool 11 3 240 to camshafts.
The camshaft setting is correct if the special tool 11 3 240 can be fitted to the cylinder head without a gap.
Remove special tool 11 3 240.
Unfasten and remove special tool 11 3 390.
Install chain tensioning piston (1) with guide lugs engaging in tensioning rail.
Install spring (2) and screw connection (3) with new seal.
Tightening torque = 50 Nm
Install plugs with new sealing rings.
Tightening torque = 50 Nm
Check function of VANOS adjustment unit.
Fit special tool 11 3 450 with banjo bolt on oil pressure line.
Connect up compressed air (2 .. 8 bar).
Measure gap (x) between secondary tensioner and edge of sensor gear.
Note down distance 1.
Connect special tool 12 6 410 to plug connection for VANOS solenoid valve.
Connect positive clip to battery connection point.
To adjust camshaft, connect negative terminal to vehicle earth.
CAUTION! Reversing terminals on special tool will destroy installed diode on VANOS solenoid valve. Solenoid valve remains serviceable but current spikes can give rise to faults in vehicle circuit.
Measure gap (x) between secondary tensioner and edge of sensor gear.
Note down distance 2.
Determine control travel:
Distance 2 - distance 1 = length of stroke.
CAUTION! If adjustment stroke is less than 8.5 mm, VANOS adjustment unit must be readjusted.
Remove special tools 11 3 450 and 12 6 410.
Fit cable duct.
Fit suspension lug.
Fit oil pressure line with new seals.
Tightening torque = 32 Nm
Install solenoid-valve plug-in connection.
Remove special tool 11 2 300 (setting mandrel). Assemble engine.