Toothed Belt, Removing and Installing
Notes: Mark the direction of rotation before removing the toothed belt. If a used belt rotates in the wrong direction when reinstalled, this can result in breakage.
1 - Engine support
^ Removing (removing toothed belt)
2 - 45 Nm
3 - Toothed belt guard, top
^ To remove belt guard, it may be necessary to unbolt retainer for coolant return line (for turbocharger).
4 - Toothed belt
^ Mark direction of rotation before removing
^ Check for wear
^ Do not kink
5 - Idler roller
6 - 27 Nm
7 - 65 Nm
^ Use counter - hold 3036 to loosen and tighten
8 - Camshaft sprocket
^ For exhaust camshaft.
^ To remove and install, first remove toothed belt
^ Note installation position; camshaft sprocket is installed with smaller side facing out and TDC marking for cylinder 1 visible.
9 - Tensioner
10 - Washer
11 - Tensioner for toothed belt
12 - O ring
^ Replace
^ Lightly coat with coolant G 012 A8 D before installing
13 - Coolant pump
14 - 15 Nm
15 - Crankshaft sprocket
^ Contact surface between sprocket and crankshaft must be free of oil
^ Can only be installed in one position
16 - 90 Nm + 1/4 turn (90°) further
^ Replace
^ Counter - hold with 3099 to loosen and tighten
^ Place 2 washers between sprocket and retainer when screwing on retainer
17 - 15 Nm
18 - 20 Nm
19 - Toothed belt guard, center
20 - Toothed belt guard, bottom
21 - 10 Nm
Removing toothed belt
Special tools, testers and workshop equipment required:
^ 10 - 222A
^ 10 - 222A/1
^ Engine, disassembling and assembling
^ Engine in vehicle
^ Disconnect air duct at bottom of right - hand longitudinal member (air duct leads to charge air cooler).
^ Remove noise insulation panels in center and on the right - arrows -.
^ Remove ribbed belt and tensioning element.
^ Detach coolant expansion tank and power assisted steering reservoir - arrows - and move to one side with the hoses connected.
^ Disconnect vacuum hose from activated charcoal filter and from connection on throttle valve.
^ Unplug electrical connectors on coolant expansion tank and activated charcoal filter.
^ Remove toothed belt guard (top).
^ Set up engine support bracket 10 - 222 A with supports 10 - 222 A/1.
^ Fix retainer 3180 to right lifting eye and attach to engine support bracket 10 222 A.
^ Lift engine slightly with spindle of engine support bracket 10 - 222 A.
Notes: Lift coolant expansion tank and power assisted steering reservoir and tie them in place on the engine support bracket.
^ Set crankshaft to markings for TDC of No. 1 cylinder - arrows - by turning central bolt on crankshaft sprocket in direction of rotation.
^ Remove vibration damper, making sure not to change the TDC position.
^ Remove center and bottom sections of toothed belt guard.
^ Unbolt engine support from engine console and engine console from body - arrows -
^ Unbolt connecting piece between engine console and body. - Take out engine console.
^ Remove bolts for engine support - arrows - , but do not take out the engine support.
Notes: To remove the bolts for the engine support, raise or lower the engine slightly as necessary via the spindles on engine support bracket 10 - 222A.
^ Mark direction of rotation of toothed belt with chalk or felt pen.
^ Screw M5x55 stud - 1 - into toothed belt tensioning element. Screw hexagonal nut - 2 - onto stud - 1 - using a large washer - 3 - .
^ Only tension piston of tensioning element as far as necessary to secure it with a locking pin (e. g. from lifting appliance 2024A) - arrow - .
^ Pull out toothed belt through space between engine support and cylinder block.
Installing toothed belt (setting camshaft timing)
Notes:
^ The position of the toothed belt must be set as described below, even after repairs in which the belt is only taken off the camshaft sprocket.
^ When turning the camshaft the crankshaft must not be at TDC (danger of damage valves/piston crown).
^ Align camshaft sprocket mark with marking on cylinder head cover.
^ Place toothed belt on crankshaft sprocket (note direction of rotation).
^ Install toothed belt guard, lower part.
^ Install vibration damper (note installation position: hole in vibration damper is over projection on toothed belt sprocket).
^ Align vibration damper marking with marking on lower part of toothed belt guard.
^ Fit toothed belt onto coolant pump, then tensioning roller, and finally camshaft sprocket.
^ Pull out locking pin - arrow - and loosen piston of toothed belt tensioning element.
^ Unscrew stud - 1 -.
^ Turn crankshaft two complete turns in engine direction of rotation, set again to to TDC and check adjustment.
^ Install engine support and console.
^ Remove engine support bracket 10 - 222 A with retainer 3180.
^ Install toothed belt guard (center and top sections).
^ Install ribbed belt and tensioning element.
^ Install and secure coolant expansion tank and power assisted steering reservoir.
Tightening Torques
1) Stretch Bolts - replace.
2) 90 degrees is a quarter turn.