Caution: The referenced dowel pins are intended ONLY for checking crankshaft position during various engine rebuild procedures. DO NOT use them as locking tools to hold the crankshaft still while loosening or tightening pulley or flywheel/drive plate bolts.
1. TDC is the highest point in the cylinder that the piston reaches during a revolution of the crankshaft. Each piston is at TDC at the end of the compression stroke and also at the end of the exhaust stroke. However, for ignition timing purposes, TDC at the end of the compression stroke is taken into account. Cylinder #1 is at the end of the engine facing the transmission.
2. When piston No.1 is set to TDC, the timing mark on the camshaft gear should be aligned with the pointer on the outer cover of the timing belt (the mark on the pulley can be seen through the slot in the cover, below the pointer). Additionally, the timing mark on the flywheel must be aligned with the TDC mark on the clutch housing.
3. To align the timing marks, you need to turn the crankshaft. This can be done with a wrench on the crankshaft pulley bolt. To improve access to the pulley bolt, jack up the front right corner of the car, remove the wheel and remove the wheel arch liner (attached with plastic staples). To make the crankshaft turn more easily, remove the glow plugs (Chapter Engine electrical equipment) or fuel injectors (Chapter Power and exhaust systems).
4. Looking through the opening in the clutch housing, turn the crankshaft so that the timing mark on the flywheel aligns with the TDC (0°) mark on the clutch housing (refer to the accompanying illustration).
5. On F8Q models, remove the three mounting bolts and the upper plastic drive belt/right engine mount cover from the upper bracket, noting the location of the mounting bolts. On F9Q models, remove the mounting nuts and the sound deadening cover.
6. Make sure that the timing mark on the camshaft gear is aligned with the pointer on the outside of the drive belt cover (refer to the accompanying illustration). Now piston No.1 is set at TDC on the compression stroke.
7. You can check the position of the crankshaft as follows. If necessary, remove the air cleaner housing assembly (Chapter Power and exhaust systems).
8a. The exact position of the crankshaft can be checked by inserting the locating pin - Renault Mot. 861 tool (early version) or Mot/1054 (the latest version).
8b. To do this, unscrew the plug from the front left end of the cylinder block, next to the base of the oil level dipstick tube.
8b. Insert the dowel pin until it fits into the groove in the crankshaft. You may have to turn the crankshaft forward or backward slightly (refer to the accompanying illustration).
Note: Do not attempt to rotate the engine with the pin installed. If the engine must be left in this condition for an extended period of time, it is recommended that a warning note be left in the engine compartment.
9. Finally, remove the locating pin and install all removed components.