Golden Dragon XML6125CLE, Руководство по ремонту

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Steering System SR-19
Initial inspection
With respect to the steering problem, if you (service man) can confirm what users are actually relaying
and ensure you are discussing a same issue with them, you will save a lot of time in handling problems.
For example, if the customer tells you that steering is difficult, you should ascertain the specifics: is it left
steering difficulty, right steering difficulty, pivot steering difficulty, intermittent steering difficulty or no
boosting at all.
If any one of these problems is possible and under the condition of safety, drive the vehicle yourself. If
you are not familiar with driving, ask the customer to drive the vehicle and sit beside him, with your hand
on the steering wheel so as to gain a direct understanding of the problem. As the customer generally
drives the vehicle with a load, you may load the vehicle if necessary in searching for the cause. Once you
have confirmed what has really been reflected by the customer, do not hurry to remove the steering gear
or oil pump. In fact, in most cases, there are many other parts in the steering system that may cause a
steering fault. Inspect these parts first before inspecting the steering gear.
Check the steering wheels first. Find out if the tyres have proper and balanced pressure, suitable size, and
if they are seriously worn or damaged.
Then check the front wheel alignment (kingpin caster, inclination, camber and toe-in) and the tightness of
steering tie-rod, ball joint and kingpin. If the customer has replaced the oil pipe, the oil pipe may be
wrongly installed, be too small in small diameter, or may be blocked, twisted or bent too much, leading to
unsmooth oil flow or insufficient flowrate. Oil pipes not conforming to requirements should be replaced.
Now check the power steering oil tank. Make sure the oil reaches the specified level. If the pump adopts a
belt transmission, check if the belt is slipping. The belt may be tight but may also be slipping due to wear.
A slipping belt does not always screech. Please adjust the belt according to the technical specifications.
If there is no problem on the above checking, the reason led to the malfunction of steering maybe the
insufficient pressure or insufficient flow; in this case, must more careful analysis, including hydraulic
pressure test.
Caution:
When the hydraulic test is completed and the oil piping is reconnected, check the oil level in the tank
and discharge the air in the system (refer to “Oiling and discharge of steering system”)
Symptoms Possible causes Repair/preventive measures
No hydraulic
boosting at a
cold start
The vane of hydraulic pump
can not freely extend out (vane
pump only). Instantly increase the engine speed to throw out the
vane by its high speed rotation so as to start the oil
pump (for a seldom and short time case, there is no
need to check the oil pump.)
No or instable
hydraulic
boosting Oil pump failure Repair or replace the oil pump.
A. Belt transmission: the
transmission belt of oil pump
is loose or broken.
B. Gear transmission: the
gear or the key is damaged. Tension the belt or replace the belt
Replace the gear.
Damaged pressure safety valve
of oil pump or dirt in oil lead
to poor performance. Replace the pressure safety valve of oil pump or
change the oil and clean the valve.
Damaged flowrate control
valve of oil pump or dirt in oil Replace the flowrate control valve of oil pump or
change the oil and clean the valve.
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