Camshaft, Engine
Removal
Model 116.120
1 Disconnect regulating linkage to remove cylinder head cover. Pull out locking eye of longitudinal regulating shaft (arrow).
Model 123
On models 116.120 and 123, pull longitudinal regulating shaft out of rubber mount in forward direction and remove in rearward direction.
Model 126.120:
Model 126.120
On model 126.120, pull longitudinal regulating shaft out of guide lever in rearward direction and remove in forward direction.
On models 123 with automatic transmission 722.303 (W 4 A 040) and 126.120, pull off central plug for vacuum lines (71) or vacuum lines. Disconnect Bowden wire, compress black plastic clip (arrow) and pull Bowden wire out of holder in rearward direction.
2 Remove rocker arms together with rocker arm brackets. Service and Repair
3 Remove slide rail in cylinder head. Pull out bearing bolt by means of impact puller.
4 On engines with EGR (USA) remove pipe line between EGR valve and exhaust manifold (arrow). Unscrew shielding plate (10) for this purpose.
5 Unscrew closing plug of chain tensioner and remove compression spring. Service and Repair
6 Set crankshaft to ignition TDC.
Rotate crankshaft with tool combination for this purpose.
7 Mark camshaft sprocket and timing chain in relation to each other.
8 Remove camshaft sprocket.
To loosen necked-down screw, apply counterhold to camshaft sprocket by means of a screwdriver or a steel bolt.
9 Remove compensating washer.
10 Unscrew camshaft bearing screws by means of screwdriver socket (10 mm).
Unscrew nuts M 8.
11 Remove camshaft together with camshaft bearings and oil pipe.
Pay attention to dowel pins.
Loosen stuck camshaft bearings by means of light blows with a plastic hammer.
12 Pull camshaft out of camshaft bearings in rearward direction.
Installation
13 Provide camshaft bearings, camshaft bearing journals and cams with engine oil.
14 Slip camshaft from the rear into camshaft bearings.
15 Mount camshaft with camshaft bearings and oil pipe.
Pay attention to dowel pins.
16 Tighten camshaft bearing bolts (cylinder head bolts) from inside out as specified.
On engines with hex. socket cylinder head bolts, slightly loosen the remaining 14 cylinder head bolts also from inside out individually and tighten to 100 Nm.
Tighten M 8 nuts to 25 Nm.
17 Rotate camshaft manually to check for easy operation.
If camshaft is hard to rotate, proceed as follows:
Loosen camshaft bearings individually. Then rotate camshaft each time.
Repeat until the binding bearing point is found. Depending on sag of camshaft, touch up pertinent camshaft bearing at base (arrows) on a surface plate.
18 Slip compensating washer on journal for camshaft sprocket.
19 Mount camshaft sprocket. Pay attention to color marks.
Tighten necked-down screw to 80 Nm. For this purpose, apply counterhold to camshaft sprocket by means of a screwdriver or steel bolt.
20 Install slide rail.
21 Place compression spring into chain tensioner and tighten closing plug to 90 Nm.
22 Install rocker arms together with rocker arm bearing brackets.
23 Adjust valve clearance. Adjustments
24 On engines with EGR (USA), install pipe line between EGR valve and exhaust manifold. Screw on shielding plate.
25 Mount Cylinder head cover.
Camshaft and camshaft bearings
6 Combination screw M 6 x 12
7 3 combination screws M 5 x 10
9 3 fastening clamps
10 Oil pipe
11 Camshaft bearing crank end
12 Camshaft bearing
14 4 nuts M 8
15 4 washers 8.4
16 8 cylindrical pins 8 x 8
17 4 studs M 8 x 18
50 Necked-down screw M 14 x 1.5 x 40
51 Snap ring B 14
52 Washer
53 Camshaft sprocket
54 Compensating washer
55 Woodruff key
56 Camshaft