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The belt camshaft drive
Timing belt drives the camshaft (s). In some engine modifications and it is also used to drive the pump and the intermediate shaft. Replacement of the belt is a necessary maintenance procedures (see. The service schedule in the manual), since in the case of the "leap" to one or more teeth or a broken belt is a violation of the camshaft, pistons face valves, causing them serious damage. Therefore, during operation of the vehicle it is important to ensure that the belt always has the correct tension, no signs of deterioration in his condition (see. Manual), were serviceable associated with belt toothed pulleys / their bearings (malfunctions can also cause an open / accelerated wear the timing belt).
Removing the timing belt Removing the timing belt is conducted as follows: - Keep in mind if you intend to use removable belt again, you must install it in the same way as it was set up to this: otherwise sharply accelerated wear of the belt, and it is likely he quickly goes down. The manufacturer recommends that if the belt has served more than 50 000 km, replace it regardless of the state; Remember, timing belt breakage leads to serious malfunctions of the engine; - Before starting work securely support the vehicle at the site handbrake, set Chock the wheels, disable the ignition system by removing the central high-voltage wire from the ignition distributor, to short it to the engine, remove the fuel pump relay (see. Section on electrical equipment), disconnect the wiring connector by pulling the starter relay (see. section on engine-related systems); - Remove the air duct between the air cleaner and the throttle body and the crankcase ventilation hose (the latter - apart from ABU, AEA and the AEA), then remove the top casing of the timing belt from the engine, open the lever and spring clamps vyvernkv fixing screws; - If the V-belt accessory drive, remove it, then remove the serpentine accessory drive belt. - Set the piston of the first cylinder in the TDC, taking into account that some engines, you must first remove a pulley Poly V accessory drive belt (along with a pulley belt if by design) and the bottom cover belt camshaft drive to gain access to the adjusting labels Engine toothed pulley on the crankshaft; - Remove the fixing screws, and then remove a pulley for the poly V-belt drive auxiliary units (together with the pulley V-belt, if installed) from the crankshaft pulley. If possible, while easing the above threaded connections enable the gearbox the highest gear (manual gearbox) or move the selector lever to position ?�PARK?� (automatic transmission) and ask someone to hold the brake pedal. At the end of this operation again, make sure that the first cylinder is in TDC; - Remove pump pulley to be able to remove the bottom cover of the camshaft drive belt (except engines ABU, ABD, AEA); remove the bottom cover of the timing belt;
| Fig. 2.38. Location mounting nuts (all engines except the ABD and ABU)
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| Fig. 2.39. Easing (tension) of the camshaft drive belt before removal (when fitted) (ABD engines and ABU)
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NOTE To remove the belt it is necessary to weaken. All engines, except engines and ABD ABU, loosen the tension of the timing belt, release the central nut of a tension roller, that he turned away from the belt (Fig. 2.38). On engines ABD and ABU release pump mounting bolts, then reduce the belt tension, turn the pump toward the engine by means of the lever (Fig. 2.39). |
- Remove the belt from the sprocket, taking care to prevent its excessive twisting or kinking. Be careful not to knock the timing belt in the process of removal; - Carefully read the belt for signs of contamination or lubricant coolant. If you find such traces locate the source of contamination before continuing work; - Check the belt, trying to detect signs of damage or deterioration. Check for signs of uneven wear, peeling, sizing; Pay particular attention to the leading side of the teeth.
Installation of the timing belt Before installing the timing belt, double check as described above, the exact positioning of labels provided, if necessary, adjust the position of the shaft. Proceed depending on the engine. a) On engines ABD and ABU: - Move the drive belt camshaft sprocket at the crankshaft, taking into account the direction of rotation indicated by the marking on the belt; - Install the cover lower section of the belt; - Establish a pulley for the poly V-belt drive auxiliary units to the crankshaft pinion, bearing in mind that the offset mounting holes allow assembly in only one position, and then insert and tighten bolts to torque; - Enter into engagement teeth belt camshaft drive and toothed crankshaft pulley, and then place it in the water pump pulley and camshaft so that sbeg drive belt was taut, t. E. That all the slack of the belt was in the part which passes over a pulley of the water pump; - Insert the screwdriver between the solid projections on the case of the water pump and using it as a lever, turn the water pump so as to remove any slack in the belt (see. Fig. 2.39); - Check the belt tension, holding it with your fingers at a point midway between the toothed pulley of the water pump and camshaft and twisting it; tension can be considered sufficient if the belt is not twisted more than a quarter turn; - Rotate the crankshaft two full revolutions and re-install the piston of the first cylinder in VMT and recheck the belt tension and adjust if necessary; - Tighten mounting bolts of the water pump the demanded moment. b) In the engine AEA: - Enter the toothed belt in engagement with the crankshaft pulley and then lay the strap, as required in the water pump pulley and camshaft; - Place the flat side of the belt on the roller tensioner so that the front seat belt sbeg was taut;
| Fig. 2.40. Belt tension wrench Allen
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- With the Allen key to pull a belt, slide the pointer is not aligned with the cutout in the base plate tensioning mechanism (Fig. 2.40, 2.41);
| Fig. 2.41. The combination of the cut and the sliding pointer
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- Tighten the clamp bolt tensioner torque; - Rotate the crankshaft two full revolutions and re-install the piston of the first cylinder in the TDC. Make sure all matching labels, check the belt tension and adjust if necessary; - Set the upper and lower sections of the front cover, camshaft drive belt and tighten the screws. c) On engines ABF and AEK: - Move the drive belt camshaft sprocket at the crankshaft; - Install the cover lower section of the belt drive of a camshaft; - Attach the pulley for ribbed accessory drive belt to the crankshaft pinion, given that the mix of mounting holes allow assembly in only one position, and then insert and tighten bolts to torque; - The engine AEK eliminate movement of the intermediate shaft after removing the drive belt. Make sure the label of the terminals of the first cylinder on the distributor is combined with the center of the slider; - Enter into engagement with a toothed belt crankshaft pulley, and then lay the belt as required in the intermediate pulleys and camshafts; - Place the flat side of the belt on the roller tensioner, providing front taper tension of the drive belt; - Tighten the belt by turning the pliers to remove the retaining rings eccentrically mounted tensioning mechanism clockwise; - In accordance with the requirements on the engine manufacturer ABF with a tool VW210, adjust the belt tension. It is strongly advised to contact the station maintenance, the necessary equipment; - AEK on the engine check the belt tension, holding it with your fingers at a point midway between the toothed pulleys of the intermediate and camshafts, and twisting it; tension sufficient if the belt can twist no more than 1/4 full turn; - Tighten the lock nut torque tensioner; - Rotate the crankshaft two full revolutions and re-install the piston of the first cylinder in VMT and recheck belt tension and their correspondence; - Set the upper section of the front cover of the camshaft drive belt and tighten the screws. d) On engines AAM, ABS, 2E, ADZ, ADY: - Considering marking the direction of rotation to move the drive belt camshaft sprocket at the crankshaft; - To temporarily attach the pulley of the V-ribbed belt drive auxiliary units to the crankshaft pinion; - Make sure that the timing marks on the crankshaft pulley and toothed pulleys of the intermediate shaft were combined; - Enter into engagement with a toothed belt crankshaft pulley, and then lay the belt as required in the intermediate pulleys and camshafts; - Place the flat side of the belt on the roller tensioner so that the front of the drive belt sbeg was taut; - Tighten the belt by turning the eccentrically mounted tensioning mechanism clockwise; - Check the belt tension, twisting it between the toothed pulleys and the camshaft intermediate - belt must be twisted 1/4 turn; - Tighten the lock nut with the required torque tensioner; - Provernuv crankshaft several full rotations, set the first cylinder in VMT, check the alignment marks and the belt tension; - Remove temporarily installed V-belt pulley and install the lower section of the cover belt camshaft drive, then reinstall the pulley. Finally, replace the cover of the belt pulley pump belt auxiliary units; bring into operation the ignition system by connecting the high-voltage wire to the cover of the distributor of ignition, fuel system by replacing the fuel pump relay, starter. If necessary, check the ignition timing and gauge.
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