10.3. Preliminary checks
Check of angles of installation of wheels
Complaints to problems with steering and vibration are not always result of the wrong installation of wheels. They can be also caused by disbalance of wheels or tires. Also can take away the tire because of existence of defect or strong wear. Withdrawal is a deviation from the rectilinear movement on the flat section of the road when there is no hand pressure upon a steering wheel. For the correct installation of wheels before to start measurement of angles of installation of wheels, previously check:
– air pressure in all tires (has to meet standard) and wear of a protector;
– a side play in bearings of naves of wheels;
– a condition of spherical hinges (absence of side plays in them) and tips of steering drafts. Eliminate the found deviations before adjustment of angles of installation of wheels;
– beating of tires and wheels;
– a condition of a gear lath and a gear wheel in steering;
– serviceability of functioning of racks of a forward suspension bracket;
– condition of levers of a forward suspension bracket;
– possible excessive loading of the car. If excessive freight is transported by the car constantly, carry out an inspection of adjusting corners at this loading;
– reliability of the equipment used during the checking and installation of corners;
– irrespective of a type of the used equipment, the car has to be installed on the flat horizontal platform.
Satisfactory operation of the car can achieve in the widest range of the adjusting works connected with a forward suspension bracket.
If it is not possible to meet the imposed requirements and to receive settlement technical characteristics, check the car for existence of faulty elements of a suspension bracket. Make necessary repair or replacement.
If at adjustment it was not succeeded to achieve convergence size in the set limits, carry out adjustment repeatedly.
During the works performed on warranty repair or at maintenance implementation by request specialists in check and adjustment of wheels have to use as the management when performing diagnostics technical requirements which provide quite acceptable working range, and also help to prevent premature wear of tires.
The established periodic technical inspections obligatory for owners of motor transport, among other points include check and adjustment of angles of installation of wheels.
Check of a ruler for determination of size of a convergence of wheels
Reliable adjustment of angles of installation of wheels cannot be made by means of the damaged ruler with calibration violation. Check straightforwardness and calibration of a ruler not less once a month. Accuracy of measurement of size of an inclination of an axis of turn and installation of constant BORDYURNY HEIGHT can be provided only at the free exact movement of rotary tables and devices. Surely, at least once a year, you carry out their dismantling, cleaning and lubricant.
For obtaining the correct sizes of adjusting corners for forward and back wheels it is necessary to meet the following conditions:
– the drawing of a protector on all tires has to be uniform, and tires have to be in good shape;
– air pressure in tires has to meet standard;
– all rims have to be in satisfactory condition;
– it is necessary to load each of front seats loading of 70 kg;
– the fuel tank has to be filled half;
– shake the car several times to stabilize springs (also stabilize springs if the car before it was lifted). When using the adjusting equipment at which the rotary table does not fix side forces the car needs to be rolled away at first on 1 meter back, and then to return to initial situation;
– methods of adjustment of corners of wheels are various and depend on the used equipment. Observance of the instructions developed by the manufacturer of the equipment is necessary.
Adjustment of a convergence of forward wheels
Fig. 10.7. Adjustment of a convergence of wheels: A – adjusting adaptation B – coupling bolts, 20 N • m; 1 – tip of steering draft; 2 – depreciation rack of a forward suspension bracket
The convergence of wheels is regulated by change of length of steering drafts. Weaken coupling bolts of the right and left steering drafts In (fig. 10.7), then turn adjusting devices of the right and left draft And to change length of steering drafts according to technical requirements. At this adjustment the right and left steering drafts have to be identical on length.
Tighten bolts the moment of 20 N • m
Check of an inclination of an axis of turn and disorder of wheels
The inclination of an axis of turn and disorder of wheels are not regulated. If these characteristics differ from requirements, define and repair or replace all faulty, loosened, bent, received dents or worn-out details or a detail. If the problem is connected with a body, then it is necessary to perform the corresponding body works and to achieve compliance to technical requirements.