- 1. Support the car from the front. Engage fifth gear, apply the parking brake. Turn the raised front wheel. This will also turn the engine crankshaft. An assistant is needed to turn the wheel.
- 2. Place the car on a level surface. Engage fifth gear. Roll the car forward or backward.
- 3. Turn the crankshaft by the central bolt of the vibration damper (pulley) using a socket head. First set the gearbox to neutral.
Caution: Do not turn the engine by the camshaft sprocket mounting bolt, as this may overload the timing belt.
Turn the crankshaft until the longitudinal hole in the fuel injection pump sprocket is at the top in position A.
Turn the crankshaft approximately 30° in the opposite direction (position B).
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To precisely adjust the TDC position of the crankshaft, a special adjusting pin is required. In extreme cases, you can make it yourself, using the drawing as a guide.
Unscrew the plug bolt on the cylinder block (arrow). It is located at the front of the engine between the fuel injection pump and the generator.
Insert the adjusting pin into the hole.
Turn the crankshaft clockwise with a spanner until it rests against the adjusting pin. This will bring the crankshaft exactly to the TDC position.
Insert the camshaft dowel pin or a suitable 6mm diameter rod.
Insert the injection pump installation pin. This requires a special pin or rod with a diameter of 9.5 mm.
Loosen the timing belt tensioner mounting bolt (E). Press the tensioner away from the timing belt (A) and tighten the bolt back. A special key is required for this bolt.
Caution: If a lot of force or a chisel was used to loosen the bolt, the bolt and tensioner must be replaced. Otherwise, the tensioner may fail soon, causing serious damage to the engine. (C - oil filter holder).
Loosen the timing belt tensioner mounting bolt (D). Press the tensioner away from the timing belt (B) and tighten the bolt back.
Loosen the four camshaft sprocket mounting bolts so that the sprocket moves freely within the longitudinal holes.
Loosen the three bolts securing the fuel injection pump sprocket so that it moves freely in the longitudinal holes.
Remove both timing belts. The engine must not be turned after the timing belt has been removed, otherwise the valves and pistons may be damaged.
Turn the belt tensioner and intermediate sprocket, check them for cracks, scratches and other damage and, if necessary, replace the parts. Check the bearing for ease of movement, for jamming and, at high rotation speeds, for excessive noise and, if necessary, replace it. Check the plastic intermediate sprocket for wear of the teeth (the size in the middle is smaller than the size at the edges) and, if necessary, replace it.