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I.1.2.2 Steering system maintenance
I.1.2.2.1 The steering system maintenance consists in regular inspection of the steering
gear fastening, the piping, the free travel of the steering wheel as well as in servicing the hydraulic
system assemblies. Such units as pump and steering gear shall be repaired in specialized service
centers.
I.1.2.2.2 Steering hydraulic system oil change:
1. Warm the oil in the hydraulic steering system up to at least plus 20°
С
.
2. Lift up the front part of the truck so that the wheels have no contact with the ground or
place the truck front wheels onto the turning circles.
3. Disconnect the drain pipe from the tank having placed the reservoir for the drained oil
first.
4. Start the engine for 10 sec max to have the oil flowed out of the oil tank and the
pump.
5. Stop the engine and turn the steering wheel to the right and to the left several times to
remove the rest of the oil.
6. Clean the tank from the outside. Remove the old filter; replace it with the new one.
Connect and fasten all hydraulic connections prior to the refilling the system with the oil.
7. Pour the oil into the tank a bit lower than the upper mark of the filler plug gage.
8. Start the engine for 5 sec max; then add oil. Continue adding oil preventing air coming
into the hydraulic system due to the oil level lowering during bleeding.
9. When oil reaches the upper mark on the gage; turn the steering wheel to both sides
several times until there are no air bubbles in the tank. Add oil if need be.
Check the oil level with unscrewed plug of the filler neck.
I.1.2.2.3 Adjustment of the steering gear valves actuation.
Check and adjust the steering gear limiting valves actuation (if required) upon the re-
placement of drop arm or drop arm rod or steering gear.
I.1.2.2.3.1 Operation description
Operation shall be done on an equipped truck placed over the inspection pit, on the hori-
zontal hard and even bearing surface. It is recommended to place a turning table or two metal
sheets with grease between them under each wheel.
Before starting work it is necessary to fill the hydraulic system with oil and bleed the air.
To adjust hydraulic limiter of the pressure in the steering gear at max turning angles if steerable
wheels it is necessary to do the following with shut-down engine:
- remove plugs 2 & 8, Fig. I.6;
- unscrew the adjusting screws 3 & 7 by 3-5 turns with a screwdriver without considera-
ble effort;
- connect pressure gage to the outlet on the high pressure turning elbow in the steering
gear having removed the plug from the connector first.
Measure the pressure in the hydraulic system with steerable wheels turned to the extreme
position with the turn limiter thrusting against a pad. Check pressure always at rated engine crank-
shaft speed (starting from appr. 1200 rpm).
