STEERING 21 Toe settings affect three major areas ofperformance: (a) Tyre wears (b) Straight-line stability and (c) Vehicle handling characteristics In case of TATA NANO, ONLY TOE IN adjustment is required. Following precautions are to be taken before commencing wheel alignment: 1. Car should be unladen and parked on level surface. 2. Front and rear tires should be inflated to correct pressure (28 and 30 psi respectively) 3. Ensure that bushes in the front/rear suspension are in satisfactory condition. 4. Ensure that front rear & suspension fasteners are tightened to their specified torques. 5. Also ensure that there is no visible damage to any of the suspension parts like lower link bushes and struts. 6. Ensure that there is no play in steering linkages and suspension ball joints. 7. Ensure no tyre wear on any wheels. If so replace the respective tires. Procedure for steering geometry adjustment (wheel alignment) on vehicle: Front wheel alignment data (Unladen condition Camber angle 1.0° (+ve) (fixed) Castor angle 7.4°(fixed) Toe-in 15’ ± 5’ Wheel lock angle (Outer) 37° LH/RH variation in castor 45' Rear wheel alignment data (Unladen condition) Camber angle 0.75° (+ve) (fixed) Toe-Out 9’(fixed) NOTE: a) Please followmanufacturer’s (of tire replacement machine)manual for wheel alignment instructions, recommendations and any other addi tional information. b) All adjustments for wheel alignment are tobe done inUNLADENCONDITIONONLY. c) Only TOE INvalue at fronthas tobe adjustedwhile doing wheel alignment. Restof thevaluesremains fixed i.e. NOadjustmentsare required. Refer thegiventable for standard values. 1. Steering rack & pinion gear comes with 1142 mm (nominal) length between centers of the ball joints with tie rods parallel to the rack. (As shown in following figure) Ensure that number of threads of outer ball joints exposed out of the tie rod tube is same on LH and RH side. 2. Rotate the steering wheel from lock to lock. Measure the number of turns. 3. Bring the steering gear to centre by rotating through half the number of measured turns. 4. Remove the steering wheel & refit it so that spokes & mascot (T-emblem) are correctly positioned. 5. Ensure that both front tires are in straight ahead position. Tighten the steering wheel nut to specified torque. 6. Fix the outer ball joints into the steering arm of suspension and rotate the steering wheel to bring the spokes to the correct position. 7. Adjust toe-in as given below. a) Toe-in is adjusted by varying the length of tie rods after loosening their lock nuts (as shown in above figure). After adjusting the length of tie rods recheck toe-in and tighten back the lock nuts. Increasing length of tie rod will reduce the toe-in and vice-versa. b) While adjusting toe-in, adjust the length of both tie rods by rotating them in the same direction such that their lengths remain equal at all times. 8. Check thepositionof theT-emblemand the spokes If the steering wheel is not centered, adjust the tie rod lengthsby reducingoneand increasing the other so that in the SAP (Straight Ahead Parked) condition the toe is correct and yet steeringwheel is centered. NOTE: After setting / adjusting steering geometry (i.e Toe), connect the diagnostic tool and follow the instruction for ECU learning. This is applicable for all NANO variants fitted with EPAS.
RkJQdWJsaXNoZXIy MTIwNTUz