Chapter two Tests and Adjustments of Four
Contents
1. but there are static balance test marks on the tire make sure that the air valve nozzle is aligned with the static balance test marks 6L Tire pressure Check the air pressures of all the tires including the spare tire with the barometer Make proper adjustments if the air pressure does not meet the specifications Strictly follow the specified air pressure in filling the tires with air During the air filling the air pressure should not exceed the nominal air pressure by 10 The tire with filled air should be placed separate from the wheel mounted on the car Before doing the positioning of the four wheels please check the air pressures of the four wheels and make proper adjustments so as to meet the specified air pressure air hole 7U Air leakage Make sure there is no air leakage at the air valve Checks of air valve nozzles SL Rim sections and tires non circularity 1L Lift the car and support it securely 2 Place the probe of the dial gauge on the rim section and measure the extent of non circularity for each turning of a circle Limit for non circularity Unit mm Longitudinal 1 5 0 06 Sideways 2 5 0 10 steel rim section Jf 2 0 0 08 aluminum rim section Inspection on the tire non circularity 3L Replace the tire if necessary 9 Readjustments of tire positions In order to extend the operational life of tires and to determine the tears and wears of the tires readjustments of tir2. and adjust the toe in 1 Make preparations prior to the adjustments as required by the tester Use the steering wheel limiter to fix the steering wheel in the straightforward direction the steering wheel must be in the center position 5 degrees and the lower clamping flange of the steering axle should keep horizontally leveled 2 Loosen the locking screw nuts 1 of the steering horizontal drawbar 3 Remove the elastic protective clip ring 2 with a pair of pliers 2 Attention Replace the clipping ring if it is not elastic enough 4 Turn the toe in adjustment rod to adjust the length as needed till it meets the specified value 5 Tighten the screw nut 1 and re install the protective elastic clip ring 2 check to see 1f the locking screw nut is tight enough and if the position of the protective sheath is correct or not 6 Upon completion of the adjustments for the front wheel toe in check to see if the steering wheel is leveled If not loosen the locking screw nut of the steering wheel and adjust the steering wheel to the leveled position Tighten the locking screw nut till it meets the torque specification 27 33Nm 4 Check and test the front wheel steering angle After the horizontal drawbar joint is replaced or the toe in is adjusted the steering angle should be checked If it fails to meet the specifications the length of the left and right horizontal drawbars should be checked and adjusted IV The t
3. Four Wheel Positioning Section One Basic Tests and Checks Preparations prior to adjustments I Checks prior to adjustments 1L Checks on tire air pressure 2L Checks on car body IL Check the tire air pressure and adjust to the specified pressure Standard air pressure for tires kPa Front wheel 220 220 250 2 Check the spacing of front wheel bearings and replace the front wheel bearings when necessary 3 Check the status of the wheel outer rims as well as the status of the wheel sections and tires 4 Check to see if the ball joint of the horizontal draw bar for turning is too loose 5 Place the car on a leveled ground without any luggage or passenger 6 Make sure that the left and right heights from the wheel center line to the dasher do not exceed the standard heights 7L Check to see if the absorber performance is normal II Rim section and tire 1 Visual checks Check the tires and rim sections and make proper replacements if any cracks damages deformations or other defects are detected on the rim sections or tires Tears and wears of tire 2 Tire tears and wears 1L Check the depth of the remaining tire textures The depth of the remaining tire textures as shown in the Figure Standard tires 1 6mm min Snow ground tires 50 tire textures O 20 In the case that the wear and tear indication Wear position Wear position belt is exposed the tire must be replac
4. diagonal sequence till the specified torque of 110 10N m is applied It is not allowed to use impact wrenches that might cause damages to the wheels or insufficient tightness or excessive tightness It is not allowed to apply lubricating grease onto the wheel screws For the completed assembly of wheels and tires the wheel screws should be re tightened after the car runs for 100km so that the specified torque is assured The checks on the torque of the fixing screws are one of the routine maintenance items 20 When tightening the screw nuts the cross approach is applied The extent of tightness Should be close to each other and the wheels should be able to turn freely When the final tightening is made the wheels should be positioned on the ground 3 Install the decorated covers or place the decorative covers as needed When the clip type decorative covers are installed they should be driven in either with hands or by way of rubber hammering tools III Checks on the looseness of wheel bearings IL Check the axial spacing of the bearings Maximum 0 05mm 2 Check the bias of the bridge hub Maximum 0 05mm IV Checks on the looseness of front suspension system V Checks on the looseness of turning transmission rod system VI Checks on ball joint looseness VII Checks on the normal performances of absorbers IL Check to see if there is any oil leakage 2 Check to see if there are any tears and wears of t
5. e positions should be carried out for every 6 000km 3 750 miles of driving As shown in the Figure Readjustment of tire positions Attention Best quality tires must be used for the front wheels After readjustments of tire positions make sure that the air pressures for the tires are adjusted to the specified air pressure values 10 Adjustment of tire balance After the tires are filled with air fix the protective capsfor the air valve nozzles tightly and then make the testson dynamic balance Place the balance blocks with appropriate weights on the inner and outer edges of the rims as required According to the specifications the imbalance of the final assembly should be no larger than 100g cm which is approximately equal to the 5g balance blocks on the inner and outer edges of the rims It should be noted that at most one balancing block 1s allowed to be placed on each side of each wheel with the maximum mass no larger than 70g During the process of assembling excessively heavy shocks should be avoided to the balancing blocks In the case that excessive shocks are felt the balancing blocks should be replaced in time The balance blocks taken down in the replacement should not be used again 11 Installation 1L When making the assembly of the euibon wheels and tires first fix the wheel screws onto block the hubs manually and tighten them slightly Then use special tools to tighten the screws in the
6. ed Indication points for tire tears and wears 3L Abnormal tears and wears of tires The abnormal tears and wears of the tires as ry F R 53 22 gd Center wear shown in the right figure might occur Refer to the following table for the possible causes and the approaches for handling the trouble C a Hs BS 222833 32823 PRE ee TD Toe in and toe out wear Unilateral wear Tears and wears of tire Possiblecauses Approaches for handling Insufficient tire air pressure Test and adjust tire air pressure tears and wears on both sides Turning in fast speed Slow down car speed Tire positions not re adjusted Re adjust tire positions Excessively high tire air pressure Test and adjust tire air pressure Tire positions not re adjusted Re adjust tire positions ef Adjust the toe in Camber angle incorrect Adjust repair or replace the parts of the axle and suspension system Suspension system defective Repair or replace the suspension system Tires not balanced Make dynamic balance of tires or replace the tire Brake drum or disk not circular Make alignment or replacements Other mechanic troubles Make alignment or replacements Tire positions not re adjusted Readyjust the tire positions 4 Points of attention for the rim sections and tires 1 Do not use the under standard rim sections or tires 2L The aluminum alloy rims are easy to be damaged by sc
7. he assembly sheaths 3L Check the resistance of the absorbers Make proper replacement if any incompliance is detected Section Two Positioning of Rear Wheels It is recommended to use the four wheel positioning device for the chassis of this car model which applies the positioning approach by way of axis thrust In the position adjustments by way of axis thrust the toe in of the rear wheels may have impacts upon the toe in of the single front wheel Therefore when doing the four wheel positioning the adjustments of the rear wheels are generally done before the adjustments of the front wheels Besides the camber angle of the rear wheels is adjusted before adjusting the toe in angle followed by the adjustments of the camber angle and toe in angle of the front wheels I Measure the height of the car Before measuring the height of the car first increase the air pressure of the tires to the specified value make sure that the air pressures for the left and right tires should be identical 1 The front measuring point The height of the center point from the ground to the link screw nut for the lower control arm assembly and the front turning joints is to be measures The car body height of the left and right wheels should be basically the same 2U The rear measuring point The height of the center point from the ground to link screwnut for the rear bridge and the absorber is to be measured The left and right body heights s
8. hould be basically the same Attention Before testing and checking the wheel positioning the car should be first adjusted to the specified height If the car height does not meet the specification check the front and rear suspension systems of the car to see if there are any damages or deformations II Place the wheel positioning device or the positioning tester on the wheel 1 Install the instruments in the way as specified by the manufacturer of the devices 2 Make tests and adjustments on the car as required by the equipment The specifications for the positioning are as follows Rear wheel assembly toe in 20 40 Single rear wheel toe in 10 20 Rear wheel camber angle Thrust angle 13 10 Section Three Front Wheel Positioning I Measure the car height Do the measuring and adjustments in the same procedures as the ones for the car height measurements for rear wheel positioning II Place the wheel positioning device or the positioning tester on the wheel Install the instruments in the way as specified by the manufacturer of the devices III Check and adjust the front wheel main pin backward tilting angle main pin interior falling in angle wheel camber angle as well as the wheel toe in and steering angle Specifications The requirements for the front wheel positioning are as follows Main pin backward tilting angle 3 15 30 Front wheel camber angle 465 1 30 Single front
9. ion of seat Panai Insufficient tire air pressure Adjustment steering wheel Broken or damaged front wheel bearings Replacement Faulty steering system Check Faulty suspension system Check Abnormal tire air pressure Adjustment i Excessive tears and wears of tires or Check Lopsidedness TS l unevenly distributed tears and wears of steering Faulty steering system Check Faulty braking system Check Faulty suspension system Check wheel Inconsistent air pressures for the tires on both Adjustment sides Unstable Deformed rim section or tire Repair or replacement movement Loose wheel screw nuts Tightening Faulty steering system Check Faulty suspension system Check braking Faulty braking system Check Insufficient tire air pressure Adjustment Heavy steering Faulty steering system Check Faulty suspension system Check Incorrect wheel positioning parameters Check Poor operation Insufficient tire air pressure Adjustment of steering Faulty steering system Check wheel to return Faulty suspension system Check to straight for Incorrect front wheel main pin backward Adjustment ward direction tilting
10. oe in and camber angle of the rear wheels cannot be adjusted Check the camber angle and toe in of the rear wheels If they fail to be in the specified limits check to see if there are any deformed parts Replace the defective parts Section Four Guide to Trouble Shooting Problem Possible cause Countermeasures Excessive tear and wear or unevenly distributed tears and wears of tires Tears and wears of tires ahead of scheduled operational life Tire noises Road surface noises or vibration of car body As indicated later Incorrect tire pressure Incorrect wheel positioning parameters Incorrect tire air pressure Tears and wears of tire Insufficient tire pressure Imbalance of tires Deformed rim section or tire Unevenly distributed tears and wears of tire Adjustment Adjustment Adjustment Check adjustment replacement Adjustment Adjustment Repair or replacement Check adjustment replacement Excessive bias of tire and rim section Replacement Loose wheel screw nuts or axle heads Tightening Vibration up Imbalance of tires Adjustment and down of Broken or damaged engine suspension Replacement steering wheel rubber Broken or damaged gear box supporting Replacement stand rubber Excessive bias of tire and rim section Replacement Loose wheel screw nuts or axle heads Tightening Imbalance of tires Adjustment Circl l E Unevenly distributed tears and wears of tire Check vibrat
11. raps Please use soft cloth when doing the cleaning Never try to use steel brushes If steam is used for cleaning the car do not allow the boiling water to contact the rim sections 3L In the case that some alkali chemical compounds such as mud water road surface mud etc stain on the aluminum alloy rim sections use the neutralizing agents to clean them off as soon as possible so as to avoid the rim sections from being damaged SL Tire replacements 1L Before installing the air valve nozzle first check to see if the air valve opening on the tire is smooth and free of rags Then apply some glycerin onto the surface of the air valve nozzle rubber or dip the air valve nozzle in the glycerin Use the special tools to exert the air pressure of 200 400N so as to allow the positioning ring of the air valve nozzle to pass the hole on the wheel which complete the installation and positioning soap solution can be used to substitute glycerin 2L Before installing the tires apply glycerin or soap solution along the tire rings Make sure that when there are light indication spot marks on the rims the test marks for tire balance should be aligned with these light indication spot marks When there are not light indication spot marks on the rim the dynamic balance test marks of the tire should be aligned with the air valve nozzle position If there are neither light indication spot marks on the rim nor dynamic balance test marks on the tire
12. tilting angle will be very small or even tending to be in the negative which makes the turning of direction easier If the car is equipped with the dynamic steering device the backward tiling angle is generally set to be relatively large positive angle which allows the driver to feel the turning of directions The increase of the positive backward tiling angle will increase the forces for turning and increase the stability in straightforward movement of the car 2 Camber angle Under normal circumstances the camber angle does not have to be adjusted after the car is equipped with the independent suspension system and wheel knuckles In the case that the wheel camber angle is detected to have bias from the allowances due to some reasons alignment can be made by way of adjusting the connecting screw nuts for the independent suspension system and the knuckles 1 First check visually to see if there are any damages on the driving system parts and components before doing the alignment Replace the damaged parts Adjustment or components if there are any The camber angle of designed and set for the front wheels by the manufacturer crew nut cannot be adjusted 2 In the case that the front wheel camber angle is detected to exceed the allowed bias loosen the connecting screw nuts for the front absorber and the knuckles and move the wheel for proper alignments 3L Toe in Special four wheel positioning testers should be used to test
13. wheel toe in angle 10 10 Steering angle Inner side 35 4 Outer side 31 44 Note The backward tilting angle is adjusted before adjusting the camber angle and the toe in angle 1 Main pin backward tilting angle This angle is assured by way of the designed configuration which makes the operational adjustments unnecessary The impacts of backward tilting angle The major function of the backward tilting angle is to keep the car moving in the straightly forward direction If the backward tilting angle is positive the inner side of the car will be lowered when the front wheel turns in directions which results in the uprising of the chassis That will increase the loads onto the knuckles If the backward tiling angles of the two wheels are identical the car will be back to the straightforward direction after turning the directions The increase of the positive backward tilting angle will increase the stability of the steering wheel but the turning forces will be increased as well The decrease of the positive backward tilting angle will reduce the stability of the steering wheel but the turning forces will become reduced The extent of the backward tiling angles will not have impacts upon the tears and wears of the tires They are used to stabilize the driving directions and ensure the automatic returning to the straightforward direction after turning If the car is equipped with the traditional mechanic steering devices the backward
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