1. Steering System:
The steering mechanism controls and changes the tractor's direction of travel, determining its safety. Inspection of the steering mechanism is crucial and should not be neglected; ensure it is in good technical condition.
Points to note:
① Check the tightness of the tie rod ball joints, steering arms, steering gear base, etc., and the locking condition of the cotter pins.
② Check the preload of the steering shaft (the method is to push and pull the steering wheel along the steering shaft axis; there should be no obvious play or wobbling).
③ Check that the steering wheel play is controlled within the range of 15-30 degrees. Adjust promptly if it is too large or too small.
④ Apply grease to the ball joints and other parts as needed.
⑤ Do not weld or repair any damaged or cracked steering mechanism parts; replace them with new ones.
⑥ If steering wheel jamming is observed during driving, stop the vehicle and troubleshoot the problem before continuing. ⑦ If steering wobbling or veering is observed during driving, the tractor should be sent for repair immediately; prolonged driving is prohibited.
⑧ If the steering feels heavy, the cause should be identified and rectified promptly.
2. Braking System:
The braking system helps the tractor reduce speed and eventually stop, and is a crucial system affecting the tractor's road safety; therefore, it must be thoroughly inspected.
Points to note:
① Check for wear on the brake lines and the tightness of the connections, paying particular attention to whether the brake lines are rubbing against the axle, frame, etc. (For small steering maneuvers, check the connection of the main and side tie rods).
② Check the brake fluid level. If insufficient, add the same type of brake fluid; do not mix different types.
③ Check the brake pedal free play. Maintain 10-15mm of free play; adjust promptly if too much or too little.
④ If the brake pedal sinks, it indicates a leak in the lines, brake cylinders, or a brake fluid backflow from the master cylinder piston; check and resolve this immediately. ⑤ When the brakes feel soft and weak, it may be due to excessive clearance between the brake drum and brake pads, hardened brake pads, or an out-of-round brake drum. These issues should be addressed promptly.
⑥ If the brake pedal feels springy, it indicates air in the braking system. The air should be bled out immediately.
⑦ Any instances of brake pull or dragging should also be addressed promptly.
⑧ After the tractor has been in motion, touch the wheel hubs of all four wheels. The temperature should be roughly uniform. If some wheels are particularly hot, it indicates that the brake drums on those wheels are worn; if some wheels are particularly cold, it indicates that the brakes on those wheels are weak.
3. Running System
The running system is the skeleton system of a transport tractor, consisting of the frame, axles, wheels, and suspension. It should be carefully inspected.
① Check the tightness of the connections to the frame and axles.
② Check the tire pressure and tire wear. If uneven tire wear is observed, find the cause and address it promptly. (Reminder: Regardless of the tractor's load or road surface condition, tire pressure should always be at the standard pressure; it should not be too high or too low.)
③ Check the preload of the four wheel hub bearings. The method is to grasp the upper edge of the wheel and turn it forcefully; there should be no play in the hub bearing.
④ When turning the front wheels, pay attention to the kingpin clearance; do not forget to lubricate the kingpin.
⑤ Check for any breaks in the leaf springs and apply lubricant to the leaf spring pins if necessary.
⑥ Stand directly in front of the leveled tractor and visually inspect the vehicle body for straightness, front wheel toe-in, and front wheel camber.
4. Transmission System:
Transmits the diesel engine's power to the drive wheels in a specific manner.
① Clutch:
a. Check the clutch free travel, generally 25-35mm. Adjust it promptly if necessary.
b. During use, pay attention to whether the clutch slips, whether disengages completely, and whether the operation is smooth.
② Gearbox:
a. Check for oil leaks.
b. During use, pay attention to whether shifting gears is smooth and whether there is any gear slippage. If any malfunction occurs, send it for repair immediately.
c. After driving, check the temperature rise of the transmission. Generally, the temperature is normal if you can lightly press the transmission housing with your hand. If you cannot lightly press it, the temperature is too high, possibly due to insufficient or deteriorated gear oil. Add or replace the gear oil promptly.
d. During driving, pay attention to any abnormal noises from the transmission. This is usually caused by excessive gear wear, loose gear shaft bearings, or gear shaft deformation. Address these issues promptly. Insufficient gear oil can also cause transmission noise.
③ Driveshaft:
a. Check the connection of the flange bolts at both ends of the driveshaft. If loose, tighten them immediately.
b. Add lubricating grease promptly. When adding grease to the cross shaft, use a grease gun with force to ensure all four needle roller bearings are lubricated. Do not add too much grease to the driveshaft extension joint (to avoid damaging the dust cover). ④ Rear Axle:
a. Check the rear axle for oil leaks.
b. After use, check the temperature rise of the rear axle bearing. A normal temperature is when you can lightly press down on the rear axle bearing with your hand. If the temperature is too high, check the quantity and quality of the bearing oil and add or replace it as needed.
c. During driving, pay attention to any abnormal noises from the rear axle. Abnormal noises usually occur when the main reduction bevel gear is excessively worn or the preload of the bevel bearing is too low, and these noises are more noticeable when the throttle is changed.
d. Regularly check the total clearance of the rear axle. A method is to shim both rear wheels, put the axle in neutral, release the handbrake, and manually rotate the drive shaft to visually or feel the clearance.
