SL 500 (129.067) V8-5.0L (119.982) (1996)
Variable Valve Timing Actuator: Description and Operation
Engine timing, valves
1
Bolt, M6 X 18
2
Solenoid with 2-pole plug
3
Washer-head bolt, M5 X 12
4
Armature with roll pin
6
Nut, M20 X 1.5, wrench size 30 mm
7
Front left cover
12
Cover
13
Camshaft sprocket
14
Adjustment piston
14a
Spiral cone spring
15
Washer-head bolt, M7 X 12
16
Flanged hub
17
Compression spring
18
Control piston
19
Retaining ring, 18 X 1
20
Sealing cap for oil passage, A18
21
Dowel pin in camshaft
22
Intake camshaft
Camshaft timing adjusters
With the engine running both camshaft timing adjusters hydraulically/mechanically rotate the intake camshafts relative to the driving camshaft
sprocket by 20° of crankshaft angle in the advanced position and back to the retarded position. The adjustment is controlled electromagnetically
through the engine control unit.
The adjustment time of about 1 second is dependent on the engine oil pressure at the camshaft adjusters and the temperature or viscosity of the oil.
The camshaft position indicator on the camshaft sprocket (13) sends the camshaft rpm signal from the camshaft position sensor as an input parameter
for the ignition control unit. The angle of rotation for the camshaft advancement is limited by circumferential stops between the camshaft sprocket (13)
and the flanged hub (15).
A spiral cone spring (14a) prevents gear play from causing noise during cranking.