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Chery A18. Manual - part 105

III. Adjustment of steering gear clearance

Locate wheel on position of straightline driving;

Rotate steering wheel to both sides;

In case that phase noise occurs from steering engine, please adjust bolt shown in figure until no noise sending

out while rotating steering wheel;

Screw down bolt for 1/8 circle (about 45°);

Road test;

In case that steering mechanism could not return to central position by itself, please loosen bolt for 15°;

Road test.

IV. Adjustment of power steering system

Connect power steering fuel pipe correctly, of which fasten moment between oil return pipe, high pressure oil

pipe and connecting interface of steering engine is 35±3Nm, fasten moment of hole bolt connecting fuel

injection pipe and power steering pump is 45±3Nm; It is recommended to add fluid after vacuumized with

special tools while adding power steering oil; criterion for adding hydraulic oil of power steering, and air

exhausting is shown as following:

Add hydraulic oil of power steering to maximum limit level of steering oil tank assembly, start engine and

drive steering pump in low speed (idle speed) to fill hydraulic oil in steering system. In process of adding oil,

it is necessary to drive vane pump by making engine operate in state of idle speed only, and add hydraulic oil

continuously and duly to prevent oil level from dropping, to make vane inhaust air.

In case that hydraulic oil in oil tank offers state of emulsify or too big pump noise occurs (under normal

condition, it is 80DB in maximum), it is necessary to exhaust air according to following sequence:

Jack up forepart of vehicle to hang up two front wheels, start engine, and turn steering wheel leftwards and

rightwards to limiting position on left and right sides (note: do not make any staying as mush as possible after

limiting position is achieved, and do not stay for two seconds above if it is necessary); exhaust air in system

out form oil tank progressively by repeating above step for several times. In the process, please add hydraulic

oil along with dropping of liquid level of oil tank until oil level achieves the indicated height.

Inspect, adjust tension of power steering belt regularly: impress 100N force on middle section of belt

vertically, maximal flexibility of belt should be less than 5mm, or adjust tension of belt to abovementioned

requirement via adjusting tension bolt.

Do not turn steering wheel to limiting position during operation, or hold at the position for 10 second above if

it is necessary. Do not perform power steering pump in state of no oil. Please stop the vehicle to perform

overhaul inspection and maintenance immediately if turning becomes difficult during operation.

V. Inspection content of steering system

Check if steering column is winding, or if safety coupling is abraded or damaged, or if springiness of spring is

ineffective; please repair or replace new one if it is damaged.

Basal inspection

(1)

Check if fixed bolt of steering system is loose.

(2)

Check if free travel of steering wheel is suitable, please check, adjust or replace part of steering system if it

is unsuitable.

Overhaul of steering tie rod

(1)

Check if buttonhead of steering tie rod is loose in globe joint, please replace buttonhead of steering tie rod

if it is loose.

(2)

Check if dust cap of tie rod buttonhead is damaged, please repair or replace if it is damaged.

Overhaul of steering gear

(1)

Check if dust cap of steering gear is broke, please replace if it is broke, otherwise water and dust can enter

easily to make part damaged on early stage. Check if clip of dust cap is fixed well.

(2)

Check if clearance of steering gear is suitable; and adjust it if it is unsuitable.

Overhaul of hydraulic strengthener

(1)

Check if hydraulic strengthener is blocked, and replace it with new one if it is blocked.

(2)

Check if bearing of hydraulic strengthener has abnormal noise, and replace it with new one if abnormal

noise occurs.

(3)

Check if leakage is existing in hydraulic system, and replace it with new one if leakage occurs.

VI. Inspection on leakproofness of power steering system

Conduct inspection on leakproofness of power steering system while prerunning. Conduct inspection in following

step:

(1) Turn steering wheel to limiting position of left side or right side quickly and hold it to makes press in system

reach maximum.

(2) Visually check if leakage is existing with steering controlling valve, seal of rack, sliding vane pump (steering

power pump), fuel pipe connector.

(3) Check if oil tank is lack of ATF oil, and check if leakproofness of power steering system is in good condition

if abovementioned condition occurs.

(4) If sealing member of gear and rack in shell of power steering gear is unsealed, ATF oil could flow into

corrugation pipe sleeve, in this case, it is necessary to disassemble turning gear and replace all sealing rings.

(5) Check if fuel pipe terminal of power steering system is leaking, please find out the reason if leakage occurs

and reconnect it again.

VII. Inspection and replacement of hydraulic power oil

Inspection on oil mass

(1)

Drive engine to operate in idle speed, turn steering wheel from one side of limiting position to the other

limiting position frequently to raise temperature of power steering oil and make oil temperature achieve

around 40-80

℃

(2)

Check oil mass in oil tank in which oil level should be on position of “max”. In case of shortage of oil,

Note: It is recommended to add oil after vacuumized with special tools while adding power steering oil, or (for

example in state of rework) criterion for adding oil of power steering, and air exhausting is shown as following:

Add oil of power steering to maximum limit level of steering oil tank assembly, start engine and drive steering

pump operating in low speed (idle speed) to fill hydraulic oil in steering system. In process of adding oil, it is

necessary to drive vane pump by making engine operate in state of idle speed only, and add hydraulic oil

continuously and duly to prevent oil level from dropping, to make vane inhaust air.

Replacing of hydraulic oil

(1)

Lift front axle of vehicle and exhaust old oil from oil tank and return tube.

(2)

Drive engine operating in idle speed, exhaust oil in same time of turning steering wheel to a limit until

exhaust hydraulic oil completely.

Note: Please complete this process as soon as possible to avoid of damaging hydraulic power pump.

(3)

Add power steering oil.

(4)

Exhaust air in steering hydraulic system completely.

Exhaust of steering hydraulic system

(1)

Check highness of liquid level, add hydraulic oil if it is necessary.

(2)

Drive engine operating in idle speed, turn steering wheel from left limiting position to right limiting

position frequently until no blister or bubble existing in oil tank. If liquid level drops, please add hydraulic

oil until oil level achieves the indicated height.

(3)

Exhaust of this vehicle type is more difficult. Blister existing in system should cause abnormal noise with

hydraulic power pump.

VIII. Fault diagnosis and debugging of power steering system

General faults of hydraulic power steering system include oil spilling, air inleakage of hydraulic driving part,

failure of power steering pump, damaged of steering control valve and damaged of mechanical drive mechanism.

Fault manifestation is multifarious, for example, steering heaviness, steering noise, steering hindering and steering

bouncing etc. Please conduct fault diagnosis immediately if fault of power steering system occurs, and conduct

debugging in time.

(I)

Difficult Steering

Fault condition

Steering of vehicle assembled with power steering ought to be lightness, but it is felt heavy while steering or it is

difficult to turn steering wheel.

Fault reason

In generally, it is caused by failure of hydraulic steering power system or shortage of power, damaged of

(1) Leak of oil tank or highness of oil is below defined demand.

(2) Terminal of fuel pipe isn’t sealed perfectly, and leak condition occurs.

(3) Air infiltrates in loop of steering hydraulic.

(4) Fuel pipe is distorted and oil duct is blocked.

(5) Tension of driving belt of power steering pomp is powerless, and driving belt is sliding.

(6) Internal abrasion and leak of steering oil pump are serious that cause output press of oil pump cannot reach

the standards.

(7) Voltage regulator in oil pump is ineffective and make output pressure become too low.

(8) Internal leakage of steering control valve and power hydraulic cylinder.

(9) Steering gear mechanism is damaged or adjusted inappropriately.

Fault diagnosis and debugging

(1)

Check if tire pressure is normal, and fill air according to formulary pressure.

(2)

Check if fuel pipe terminal of power steering system leaks, and check if fuel pipe is damaged, distorted and

crackled. Please replace new one with faulted fuel pipe; if fuel pipe terminal leaks, please fasten it. Adjust

pretightening force of top block of rack or replace rack mechanism of steering gear if it is necessary.

(3)

Check rack mechanism of steering gear, as well as turning condition of wheel at returning position and

other position. Please check winding of rack and adjusting condition of top block of rack, and adjust

tightening force of top block of rack or replace rack mechanism of steering gear if it is necessary.

(4)

Check if steering control valve is in condition of locking or NG-position returning, and replace steering

control valve if it is necessary.

(5)

Disassemble and check hydraulic power cylinder, and replace damaged parts in it.

(6)

Adjust buttonhead latches on each connecting position of steering driving mechanism to ensure free

operation of them.

(II) Whipping of steering wheel occurs during steering

Fault condition

During operation of engine, steering wheel will shake while turning it, especially in case that turn steering wheel to

limit position.

Fault reason

(1)

Driving strap of steering oil pump skids.

(2)

Liquid level of oil tank is too low.

(3)

Air infiltrates into oil channel of steering hydraulic system.

(4)

Output pressure of steering oil pump is inadequate.

(5)

Piston of voltage regulator steering oil pump is blocked.

Fault diagnosis and debugging.

(1)

Check if driving belt of steering oil pomp is sliding or driving belt is damaged. Fasten tightness of driving

belt or replace disabled driving belt if it is necessary.

(2)

Check if liquid level of oil tank meets the specification, add steering oil according to demand.

(3)

Inspect all duct terminals of steering hydraulic system, eliminate leakage of steering liquid, and exhaust air

infiltrated in oil duct.

(4)

Conduct inspection on output pressure of steering oil pump. Please disassemble oil pump if pressure is lack,

and check if oil pump is abraded, or if internal leakage is serious, or if pressure limiting valve and piston of

Content .. 103 104 105 106 ..