Repair method of small four-wheel tractor

Tractor is a self-propelled power machine, which is used to pull and drive working machines to complete various mobile operations. What should I do if the tractor fails in operation? The following is the repair method of the small four-wheel tractor I sorted out for you, hoping to help you.

Repair method of small four-wheeled tractor 1. Abnormal noise of brake drum.

A small four-wheeled tractor of Dongfanghong-170 made a loud noise when the brake drum was braked, and the mechanic stopped immediately. After disassembly and inspection, it is found that the return spring of the brake shoe is very soft, the brake shoe is burned locally, some rivets are loose and the friction plate is broken. Causes of failure: First, the riveting quality of friction plates is poor; Second, frequent emergency braking; Third, it is not clean when assembled, and sand grains are mixed in. After riveting the new brake shoe, replace the return spring, remove impurities in the brake, and operate correctly after assembly (for example, don't put your feet on the brake pedal when not braking; Try to avoid emergency braking; Keep the correct brake clearance and check and adjust it regularly), and it has been used for more than one year, with good braking and no abnormal sound.

Second, the brake drum is very hot.

A small four-wheeled tractor of Dongfanghong-180, which didn't work for a long time, found that the brakes were very hot and the uphill was overloaded. After inspection, the reason is that the mechanic set the brake too dead for driving safety, and the free stroke of the brake pedal is almost zero. This not only consumes the engine power during driving, but also accelerates the wear of the brake band, resulting in the heating of the brake drum. We lengthened the brake lever and adjusted the free travel of the pedal to 30 mm. Practice has proved that the braking is reliable and the brake drum is no longer hot.

Third, the steering wheel is idling.

A Dongfanghong-170 small four-wheeled tractor that has been used for many years found that the steering wheel and the steering wheel could not be operated synchronously during the coach's practice. After realizing the right turn, when turning left or turning back to the right, the steering wheel idles, and the guide wheel does not deflect with it, so the right turn is flexible and the left turn is slow. After many inspections, it is found that the turbine shaft and steering arm of this machine are not connected by Zhang Haiyang key, but fixed by Ping Jian (now all newly manufactured tractors are splined). Due to the long service time, the key and keyway are seriously worn. When steering, the turbine shaft rotates under the control of the steering wheel, but the steering arm does not swing with it, so that the steering force cannot be reliably transmitted between the steering wheel and the guide wheel, resulting in the steering wheel idling. We modified and expanded the keyway appropriately, added the corresponding Ping Jian, assembled and tested, and returned to normal.

Fourth, the front toe-in is normal, but the guide wheel is accelerated to wear.

During the service to the countryside, it was found that several small four-wheeled tractors were used for about half a year to 1 year, and the wear of the guide wheels reached the scrapping limit, and the guide wheels shook their heads while driving. After inspection, the toe-in value of the front wheel is in the range of 6- 12 mm, which is normal; After further analysis and inspection, the causes of excessive wear of the guide wheel are found: First, the inner bearing 7306 and the outer bearing 7304 of the guide wheel shaft are conical bearings. After 200-300 hours of use, it is necessary to check and adjust the bearing clearance and inject butter, but most mechanics don't do this, resulting in excessive bearing clearance and front wheels shaking their heads. Therefore, when using and assembling, the bearing clearance should be carefully adjusted and refueled on schedule. Second, the bushing of the steering knuckle shaft bracket is seriously worn, and the positioning force decreases, which makes the front wheel swing, which is an important reason for the early wear of the front wheel. The solution is: replace the bushing with a new one, or make a copper washer, clamp it in the bushing according to the size of the worn gap, and oil the bushing regularly. After the above maintenance, the guide wheel is normally worn and the service life is extended to 2-3 years.

Verb (abbreviation of verb) Clutch release bearing 588908 is overheated or damaged.

The clutch release bearing of small four-wheeled tractor with rotation is a sealed one-way thrust ball bearing, which only bears a small axial thrust (about 260~320 kg when separating) and generally does not bear radial force. When working, the release bearing rotates with the clutch housing, and it is very hot to touch the release bearing by hand after parking. The reason is that there is no separation gap in the clutch (due to improper adjustment or failure to adjust the gap in time after the clutch is worn), so that the separation bearing rotates with the separation rod. This not only affects the normal operation of the clutch, but also causes the release bearing to heat up, which will cause damage if it runs for a long time. Adjustments should be made as required to maintain the normal clearance between the release lever and the release bearing.

Six, the causes and elimination of the swing shaft.

A small four-wheeled tractor of Dongfanghong -200 suddenly jumped out of the swing shaft of the front axle during transportation. Fortunately, the mechanic handled it in time and avoided a vicious accident. The reason is that the newly replaced positioning lock piece of the swing shaft is too thin, which is deformed and damaged during work and loses its positioning function. When checking similar faults, we also found that some drivers used wire winding instead of locating locking pieces, which led to the above faults, resulting in car crash and death. So be sure to replace it with a new locking piece, and never replace it with a thin locking piece or iron wire.

Seven, high speed and low speed when there is a sharp friction.

Is this noise in the gearbox going to happen on the differential housing and cover? Neck cutting? Signal, if the violent grinding sound becomes a crash sound, has it already happened? Neck cutting? The parts in the differential and gearbox were seriously damaged and suffered heavy losses. When you suddenly hear grinding noise while driving, you should stop immediately, which can prevent it? Neck cutting? Failure is to avoid loss. The maintenance of the differential should be carried out according to the routine procedures.

Small four-wheel tractor 1 FAQ. What are the similarities and differences between small walking tractors and small four-wheeled tractors?

Small walking refers to a small walking tractor with engine power of 2.2 ~11.0 kw (3 ~15 HP). The chassis is equipped with two driving wheels, and it relies on manpower to maintain stability when driving. Some are equipped with self-positioning wheels at the tail, which can be operated by mechanics.

Small walking and small four-wheel structure adopts small diesel engine, and the transmission part is basically the same as that of electrical appliances. But the steering system, walking system and control mode are different.

Small four-wheel tractor has the advantages of comfortable driving, reliable operation, smooth running, good stability and safe transportation. However, the small walking tractor has the advantages of simple structure, flexible steering and good field passability, but its operating mechanism is not reasonable, the operation is laborious, the braking system is imperfect, the vibration is severe, the field of vision is poor and the operation safety is poor.

Small four wheels and small hands can be used for light-load field operations, such as rotary tillage, harrowing and sowing. After modification, it can also be used in paddy field operations, but at present it is mostly engaged in transportation operations.

2. How to check and accept newly purchased or overhauled tractors?

After buying a car, you should do the following two things: First, read the instructions carefully, understand the performance, structural characteristics and driving operation methods of the machine, and count the tools, spare parts and accessories on the car one by one, so as to be aware of them. The second is the appearance inspection and acceptance. Check whether the external parts are complete, whether the parts are installed correctly, whether the surface paint falls off, whether the bolts and nuts are fastened and whether the cotter pins are locked. If necessary, list tools, spare parts and accessories or require replacement.

The newly purchased or overhauled tractors should also be inspected as follows:

(1) Engine check (1) Starting check. Add fuel oil, lubricating oil and cooling water as needed. Shake the crankshaft with a crank to observe whether the decompression mechanism works normally, and judge whether the pressure in the compression stroke of the engine is normal by hand feeling. Start the engine. If it can't be started once, stop the engine, and check whether the starting method is correct, the position of the decompression handle is correct, and the fuel injection sound is crisp. Whether to consider the seasonal influence in winter, whether to start the water heater after heating, etc. If it can be started within three times, it shows that the starting performance of the diesel engine is good. ② Governor inspection. Pull the throttle to observe whether the speed of diesel engine increases with the increase of throttle and decreases with the decrease of throttle, and whether the speed regulation is sensitive; If the speed of the diesel engine drops sharply with the sudden contraction of the throttle and stays at the lowest speed without catching fire, it means that the governor works normally.

⑵ Check whether the gearbox is put into gear smoothly and whether there is automatic gear shifting when walking in actual operation of tractor; Whether the clutch and brake are flexible and reliable; Whether the tractor walks in a straight line and whether the front wheel swings; Whether the steering is sensitive, turn the steering wheel to the limit position and drive at a low speed to see if the minimum turning radius meets the requirements; Whether the hydraulic suspension device of small four-wheel tractor works normally.

(3) Listen, smell, touch and see. Attention should be paid to listening, smelling, touching and watching when the engine is in trial operation. Listen to the abnormal sound of engine and chassis; Smell whether there is burning smell and exhaust smoke smell; Check whether the temperature of engine parts is too high, and the normal working temperature of cooling water should be 75 ~ 95℃; See if the color of exhaust gas and the operation part work normally.

3. Why should tractors be maintained? What are the levels of technical maintenance?

During the use of tractors, due to natural and man-made factors, some parts will reduce or completely lose their working ability due to pollution, wear, looseness, abnormal work and other reasons. At the same time, with the increase of service time, lubricating oil and cooling water will gradually decrease and deteriorate. If technical measures such as inspection, adjustment, fastening, replacement, cleaning and addition are not taken in time, the normal working state of the tractor will be destroyed, and the normal working ability of some parts will be difficult to recover, which will inevitably reduce the reliability of the tractor and shorten its service life. Therefore, it is necessary to maintain the machine through technical measures, that is, technical maintenance.

Technical maintenance is generally divided into: maintenance per shift, first-class maintenance, second-class maintenance and third-class maintenance according to the cumulative load working hours of tractors.

4. What should I pay attention to when using tractors in summer?

The temperature is high in summer, if the tractor is used improperly, it will aggravate the wear and tear of parts and shorten the service life. Therefore, the following items should be paid attention to when using tractors in summer:

(1) Select the appropriate brand of engine oil. Generally, high-grade engine oil should be selected to prevent insufficient viscosity of engine oil and increase parts wear. 14 diesel engine oil is generally selected in the south, and 1 1 diesel engine oil is generally selected in the north.

⑵ Select the load correctly to avoid overload operation. For tractors that drive for a long time, stop halfway to check whether the tire temperature is too high. If the temperature is too high, the car should be parked in the shade to slowly dissipate heat, and it is not allowed to quickly cool the tires with cold water to avoid damage.

(3) Add cooling water in time. Soft water should be used for cooling water to reduce the formation of scale. When the diesel engine is short of water at high temperature, it is forbidden to add cooling water suddenly to prevent the cylinder liner and cylinder head from cracking or deformation. Diesel engine should run at low speed for a period of time, and then add cooling water after the water temperature drops.

(4) When the tractor is running, pay attention to check the inflation pressure of the tire. The inflation pressure of tires in summer should generally be 2 ~ 3% lower than the standard pressure. When parking, the tires should avoid being exposed to strong sunlight to prevent the tires from overheating and bursting.