Citroën:: Xantia:: A GRM drive belt - the general information, removal, check of a state and installation

4.2.6. A GRM drive belt - the general information, removal, check of a state and installation

General information

By means of a gas-distributing belt the drive of the camshaft, TNVD and the water pump is carried out. Rotation is transmitted through cogwheels from the forward end of a bent shaft. Remember that the break or slipping of a gas-distributing belt at the working engine leads to serious damages of a head of cylinders as a result of blow of plates of valves about the bottoms of pistons.

Replacement of a gas-distributing belt has to be made strictly according to the schedule of routine maintenance of the car (address the Head Routine maintenance). Extraordinary replacement of a belt has to be made in case of pollution by its oil, and also at emergence of the scraping sounds testifying to uneven wear of a tape or teeths.

At the same time with change of a belt it is necessary to check the water pump for existence of signs of leaks.

Removal

Removal of a belt of the GRM drive


8 — the Square opening 9 — 11 — Bolts	12 — the Axial nut of a natyazhitel 13 — the Adjusting bolt

PERFORMANCE ORDER

1. Achieve combination of openings for blocking cranked/distributive shaft and TNVD, pass throughout openings metal cores of the corresponding diameter (see Fixing cranked / distributive shaft and TNVD for the purpose of prevention of casual hit of valves in contact with pistons in the course of performing procedures of service of the car). Do not allow attempts of a provorachivaniye of the engine after introduction of blocking cores at all.
2. Uncover a gas-distributing belt (see Removal and installation of covers of a gas-distributing belt).
3. Remove a spherical receiver from the main hydraulic accumulator (see the Head Uniform hydraulic system) and you otboltit the lower cover of transmission. Ask the assistant to block a starter gear wheel the screw-driver with a wide sting, then turn out a bolt of a pulley of a bent shaft. Remove a pulley.
4. Remove a metal plate and an arm of the right support of the power unit (see Removal and installation of components of the right support of the power unit and a natyazhitel of a gas-distributing belt), then weaken an axial nut and an adjusting bolt of a natyazhitel of a gas-distributing belt. For weakening of a belt develop an arm of a natyazhitel counterclockwise. Again tighten an adjusting bolt, having recorded a natyazhitel in this situation. In case of need pass the 10-millimeter drive of a face key throughout the opening of square section provided in an arm for the purpose of simplification of overcoming resistance of a spring (see the illustration Removal of a Belt of the GRM Drive).

5. Mark with an arrow the initial direction of rotation of a belt and remove the last from the engine.

Check of a state

Attentively examine a belt on existence of stratifications, signs of uneven wear and traces of pollution by oil. Special attention should be paid to a condition of roots of teeths. The defective belt is subject to replacement. If the engine needs carrying out capital repairs, or to its test with this belt makes more than 60 000 km (36 000 miles), the belt is also subject to replacement regardless of its state. Remember that the cost of a new belt is incommensurably small in comparison with costs of repair of the engine in case of its exit out of operation as a result of break of a belt during the movement. In case of identification of traces of oiling without fail find out a source of leak and remove its cause. Carefully wipe the surface of the engine and the accompanying components around installation of a belt, having completely removed oil traces about a bottom. Check freedom of rotation of a roller of a natyazhitel, in case of need make his replacement (see Removal and installation of components of the right support of the power unit and a natyazhitel of a gas-distributing belt and Removal and installation of an intermediate roller of a gas-distributing belt).

Installation

PERFORMANCE ORDER

1. Make sure of presence on the place of the 8-millimeter bolts blocking cogwheels of the camshaft and TNVD, and also the core blocking a flywheel (see Fixing cranked / distributive shaft and TNVD for the purpose of prevention of casual hit of valves in contact with pistons in the course of performing procedures of service of the car). 2. Put on a gas-distributing belt a cogwheel of a bent shaft, having tracked observance of the initial direction of its rotation. 3. Record a belt on a wheel of a bent shaft and accurately put on it the remained gear wheels / rollers in the following order (see the illustration Removal of a Belt of the GRM Drive): a) Intermediate roller; b) TNVD cogwheel; c) Camshaft cogwheel; d) Roller of a natyazhitel; e) Cogwheel of the water pump.
4. Try not to overwind and not to bend excessively at installation a belt. For a guarantee of correctness of landing of a belt put it at first on a half of width of a cogwheel of TNVD, then get on a camshaft wheel, watching correctness of gearing of teeths on a wheel of a bent shaft and not weakening a tape tightness. Having achieved desirable result, finally put a belt on all wheels.
5. Turn out the bolts fixing the camshaft and TNVD, take a core of blocking of a flywheel (see Fixing cranked / distributive shaft and TNVD for the purpose of prevention of casual hit of valves in contact with pistons in the course of performing procedures of service of the car). 6. At the released axial nut, manually holding an arm of a natyazhitel, weaken an adjusting bolt. Slowly release an arm so that the roller nestled on an internal surface of a tape of a belt. Tighten an adjusting bolt and an axial nut. 7. Turn a bent shaft on two whole revolutions in the normal direction (clockwise). Provorachivaniye of a shaft in the opposite direction inadmissibly as the belt has to remain tense on sites between cogwheels of a bent shaft, TNVD and the camshaft. 8. Weaken adjusting and an axial nut a bolt of a natyazhitel, having allowed a spring to press densely a roller to a tape of a belt, then tighten a bolt and a nut with the required effort. 9. Make sure of correctness of combination of blocking openings by threading of cores of the corresponding diameter in them (see Fixing cranked / distributive shaft and TNVD for the purpose of prevention of casual hit of valves in contact with pistons in the course of performing procedures of service of the car). If it is not possible to enter cores, therefore the belt is established incorrectly and all procedure needs to be repeated. 10. Further assembly is made as it should be, the return to an order of dismantle of components.