"Gazelle" Gas-2705>> Brake system>> Maintenance service and repair of brake systems>> Repair of the vacuum amplifier
Working capacity of the vacuum amplifier is easy for checking up on the car (see above).
It is necessary to be convinced also of tightness of the vacuum amplifier and the return valve. For this purpose it is necessary to muffle the engine, to make endurance of 1-2 mines and to press some times a pedal. During first three pressing noise of air entering in the amplifier should be audible. If it does not occur, the vacuum amplifier or the return valve are faulty.
Completely to assort the amplifier follows only when necessary.
To remove the amplifier from the car and it is necessary to assort in a following order:
- To clear the amplifier of a dust and a dirt, to disconnect a rubber hose from the return valve, and the main cylinder from the amplifier;
- To fix the main cylinder with a tank that from it the liquid (it has not poured out allows to exclude prorolling of system after repair);
- To take out шплинт, to turn away a nut of fastening of an axis of an eye of a pusher to a pedal of a brake and to remove a spring washer, an axis and plastic plugs;
- To turn away four nuts of fastening of the vacuum amplifier to a guard передка cabins, to take out the amplifier from подкапотного spaces;

Fig. 8.9. The adaptation for dismantling and amplifier assemblage: 1 — a lining; 2 — a tube; 3 — the screw; 4 — the adaptation; 5 — заглушка; 6 — a cover; 7 — the case; 8 — a vice

- To fix two nuts on hairpins of a cover 6 (fig. 8.9) cases special заглушку 5 with the handle for turn of a cover and with a tube 2 for vacuum gauge connection;
- To establish the vacuum amplifier in the special adaptation 4 fixed in a vice 8;
- Screwing the screw 3 in the adaptation, to drown a cover 6 vacuum amplifiers before occurrence of a small backlash in connection a cover — the case 7;

Fig. 8.2. The vacuum amplifier: А1, А2, A3, А4 and A5 — cavities of the vacuum amplifier; А6 — apertures; 1 — the return valve; 2 — the sealing plug; 3 and 16 — pushers; 4 — an adjusting bolt; 5, 10, 17 — pistons; 6 — a cover; 7 and 8 — diaphragms; 9 — a persistent ring; 11 — the amplifier case; 12 — directing rings; 13 — sealing cuffs; 14 — the filter; 15 — the case of valves; 18 — a diaphragm of valves; 19 — the screw; 20 — a jet washer; 21 — a spring; 22 — a connector of pistons

- To insert into the handle заглушки the extension piece and to turn the handle before coincidence of ledges on the case with cuts on a cover. To turn away the screw on some turns and to uncover 6 with a spring 21 (fig. 8.2 see);
- To turn away a nut of a connector of pistons and to remove the piston 5 with a diaphragm 7, a plate and a persistent ring;
- To remove the amplifier from the adaptation and to take from the case a persistent cover and other details of the amplifier, to take a lock washer and to take out from a connector a pusher;
- To turn away three bolts with spring washers and to remove a connector, the piston 10 with a diaphragm 8 and a diaphragm 18 with a spring. To take out from the piston 10 jet rubber washer 20; to turn out two screws 19, 17 pushers fixing the piston in the case of 15 valves, and to take out a pusher with the piston;
- To turn away a pusher eye, preliminary having weakened a counternut;
- Slightly to compress a pusher spring, to take out a lock washer and to remove other details from a pusher. The pusher with the piston is not folding connection. To take out lock washers and to take from a persistent cover and the case 11 amplifiers directing plastic rings 12, and also sealing rubber cuffs 13;
- To remove from a connector of pistons a sealing rubber ring;
- To take out the return valve 1 of a cover of the case and if necessary to replace it.
All details of the amplifier to clear of a dirt and to examine. The details having damages or excessive deterioration to replace. It is necessary to give special attention to check of rubber details of the amplifier, and also a condition of the external polished surfaces of a connector of pistons and cases of 15 valves. In the presence of scratches and задиров these surfaces should be smoothed out accurately a small skin and to wash out.
If the filter 14 is littered, it is necessary to replace it.
Before assemblage all details of the amplifier should be absolutely pure. If necessary all details, except for rubber, it is possible to wash out in pure kerosene and to dry up a stream of compressed air.
To collect the amplifier follows in sequence, return dismantling.
At assemblage it is necessary to consider following features:
- In the case of 15 valves it is necessary to grease a rubber sealing ring with greasing ЦИАТИМ-221;
- After installation of sealing cuffs 13 in the case and a persistent cover to grease their internal surfaces with a thin layer of greasing ЦИАТИМ-221;
- To establish the collected pusher with the piston in the case of 15 valves. Slightly to press a pusher, overcoming resistance of a spring, and to screw two fixing screws 19. Screws to wrap against the stop, then to turn on on 0,5 turns everyone and закернить them for prevention отворачивания. The pusher with the piston should move without jammings and warps on 1—2 mm;
- The external polished surfaces of a connector of pistons and the case of 15 valves before assemblage to grease with a thin layer of greasing ЦИАТИМ-221;
— A surface of diaphragms 7 and 8 before assemblage to cover with a thin layer of talc, and a flute of a fillet of a diaphragm 7 for simplification of turn of a cover concerning the case to grease with a thin layer касторового oils or liquid НГ-213;
- Diaphragm 7 at assemblage to straighten so that its fillet has come for ledges on the case of the amplifier and has nestled on internal diameter of the case;
- Nut, крепящую the piston 5 to tighten the moment 5,5—8 Нм (0,55 0,8 кгсм);
- Inserting a cover 6 into the case 11, to watch, that the diaphragm 7 was not wrapped.
After assemblage to check up working capacity of the amplifier in a following order:
- To connect the return valve of 1 amplifier a hose to a depression source, for example, with an inlet pipe of the working engine; the end of a tube 2 (fig. 8.9 see) in заглушке 5 to connect a hose to the vacuum gauge;
- To create in the amplifier depression nearby 70 кПа (0,7 kgs/sm 2) and to close the crane on the vacuum pipeline. During 10 about depression should not change more than on 4 кПа (0,04 kgs/sm 2).
After check to establish between привалочной a surface of the case of the amplifier and the centre of an eye of a pusher distance of 131-133 mm as it is specified in fig. 7.6 and to tighten an eye nut.
Correct work of the main brake cylinder is possible, if the backlash between a head of an adjusting bolt 4 and привалочной a plane of a cover 6 vacuum amplifiers is equal 1,35—1,65 mm. For installation of this backlash to weaken a counternut and to rotate a bolt 4. After adjustment to tighten a counternut.
To collect the amplifier with the main cylinder and to establish it on the car it is necessary in an order, the return to dismantling.