Bulldozer Maintenance and Repair guide

01 Electrical System

The quality of technical maintenance work for various components in the electrical system has a significant impact on their service life. Therefore, it is necessary to do it carefully in accordance with the regulations.

1. Starting motor

(1) Regularly check whether the fasteners of the starter motor are firmly connected, whether the wire contact is tight, and remove accumulated dirt.

(2) Regularly inspect and keep the commutator clean, the brushes not stuck, and the pressure of the top spring normal. If the brushes are worn and the commutator surface is scorched, they should be repaired and replaced immediately.

(3) Check whether the insulation of the wires is damaged.

2. Charging generator: The charging generator should be disassembled and maintained every 1,000 to 1,500 hours of operation. The contents are as follows:

(1) Use compressed air or a blower to blow off the dust on all parts, and wipe off the oil stains on the collector rings and coils with gasoline.

(2) Clean the bearings and replace the grease. The front and rear end covers of the charging generator are equipped with rolling bearings, which are lubricated with compound calcium-based grease. The filling amount should not be too much, especially if too much is added to the rear cover bearings, it is easy for the grease to overflow and splash onto the slip rings, causing poor contact and affecting the performance of the charging generator.

(3) Check whether there is any desoldering phenomenon in the coil, rotor and rectifier components. Check if there is any open circuit or short circuit in the drying coil. If there is any desoldering, it should be repaired; if there is any burning damage, it should be replaced.

(4) When inspecting rectifier components, a multimeter must be used. It is strictly forbidden to use a megohmmeter (megohmmeter) or a power supply higher than 30V for detection. First, connect the "ten" probe to the "Ten" lead-out terminal of the generator, and then connect the "one" probe to the "one" lead-out terminal of the generator. The multimeter reading should be around 40Q. For example, connect the "one" probe to the "Ten" lead-out terminal of the generator, and connect the "+" probe to the "one" lead-out terminal of the generator. Then the multimeter reading should be above 10000Q, indicating that the rectifier component group is normal. Otherwise, it is an abnormal measurement. The generator wiring group and the connection wires of the components should be disconnected, and the rectifier components should be measured one by one with a multimeter.

(5) Check the wear condition of the brushes and whether the pressure of the brush spring is normal, as well as whether the insulation of the brush holder and the lead screw to the ground is good. If the brushes are worn too much, they should be replaced.

3. Charging generator regulator

(1) The regulator of the charging generator is a relatively precise electrical appliance. Do not adjust it at will. When it is confirmed that the regulator has malfunctioned, first check the location of the fault. Generally speaking, the first step should be to check whether the contacts are contaminated or not. The regulator spring only serves to increase or decrease the voltage data. When the spring is stretched, the data rises; conversely, it drops.

(2) The charger generator regulator should have its data checked and contacts repaired on a dedicated device every 350 working hours.

(3) When the relay contacts are separated, the gap between the armature and the core is 0.8 to 1 mm, and the gap between the contacts is 0.8 to 1 mm. The gap between the armature and the core of the voltage regulator is 1.4 to 1. "smm.

4. Other components

Other components can be technically maintained in accordance with the instructions of each manufacturer.

2

Hydraulic system

A bulldozer has three hydraulic systems, namely the main clutch hydraulic system, the steering hydraulic system and the working device hydraulic system. The oil used in the hydraulic system should be kept clean and in sufficient quantity frequently. This is one of the important conditions for extending the service life of the hydraulic system. Therefore, the oil level should be checked every 60 hours. There are three places to check the oil level. The first one is the oil filling port of the main clutch hydraulic system, located at the upper part of the main clutch. 2 is the fuel filler port of the steering hydraulic system, located above the rear axle box and to the right of the driver's seat. 3 is the oil filling port of the hydraulic system of the working device, located on the upper side of the hydraulic control box. There is a dipstick of 4 at all three refueling points within the day. It can be used to check the height of the oil level.

When the oil level is found to be insufficient, replenish the used oil in time.

2. When oil leakage is detected, the cause should be identified promptly to eliminate it.

3. If the oil is found to have deteriorated or become dirty, it should be replaced with new oil in time or drained, filtered and reused.

Under normal circumstances, change the oil every 800 to 1,200 hours of use (for new machines, change the oil every 60 hours of initial use). When changing the oil, the filter screens of the oil filters in each hydraulic system must be thoroughly cleaned. Paper filter elements can only be cleaned by shaking in light diesel oil or kerosene. It is strictly forbidden to scrub them with a brush. Magnetic oil filters should also be cleaned thoroughly. When changing the oil in each hydraulic system, the dirty oil should be drained as much as possible, and the system should be thoroughly cleaned. Then, new oil should be added in accordance with the oil usage regulations.

The main clutch hydraulic system and the steering hydraulic system can be drained of oil and cleaned as usual. When the hydraulic system of the working device is discharging oil, operate the bulldozer control lever to lift the scraper to the highest position, then turn off the diesel engine, open the magnetic oil plug at the bottom of the hydraulic control box to discharge the oil, and finally move the bulldozer control lever to make the scraper slowly touch the ground, thereby discharging the remaining oil in the cylinder. Wash after draining the oil completely. If the bulldozer is equipped with a soil loosening device, the oil discharge process of the hydraulic oil in the soil loosening cylinder is similar to that of the oil cylinder of the aforementioned bulldozer device.

Add oil with the special funnel provided randomly. After adding oil, run the diesel engine at a low speed. Lift and lower the scraper 3 to 5 times repeatedly, and then add oil to the oil tanks of each hydraulic system until the liquid level reaches the required level.

3 Regular maintenance

1. 8-10 hour technical maintenance

Before work:

A. In accordance with the relevant provisions of this manual, add oil or grease to each oil tank and lubrication point on time and in the prescribed quantity.

B. Fill up the cooling water.

C. Check if the nuts and other components are loose or missing. If so, they should be tightened and replenished.

D. Check whether each control lever is flexible and reliable, and whether the travel is normal.

E. Check whether the exhaust and sound of the diesel engine are normal and if there is any leakage.

F. Check whether all kinds of instruments are working properly and eliminate any abnormal phenomena in time.

G. If there is any oil leakage or abnormal noise from any component, it should be eliminated in time.

H. Remove the dust from the dust collection cup of the air filter.

(2) After work:

A. Clean all components and check for any loss, damage or leakage.

B. Fill the diesel tank to the brim with diesel.

C. In summer, fill with cooling water. In winter or in cold regions, drain the cooling water completely or add antifreeze.

"d Store properly.

2. 60-hour technical maintenance

(1) Follow all the provisions of the 8-10 hour technical maintenance.

(2) Adjust the tightness of the fan belt.

(3) Check whether there are any short circuits, open circuits or damages in the electrical system.

(4) Check the operation of the transmission system and the oil level. If there is a fault, it should be eliminated. If the oil is insufficient, it should be replenished.

(5) Check the tension of the tracks and make adjustments if necessary.

(6) Remove the dirt from the diesel engine oil pan and check the oil level.

(7) Check the oil levels in each hydraulic system and add oil. When a new machine is first used, the oil should be changed.

3. 125 to 150 hours of technical maintenance

(1) Follow all the provisions of the 60-hour technical maintenance.

(2) Clean the filter elements of each oil filter.

(3) Replace all the cooling water.

(4) Adjust the fan belt.

(5) Clean the air filter element or replace it.

(6) Check the oil levels of all components in the transmission system and add oil if necessary.

(7) Check the oil level in the hydraulic control box and add oil if necessary.

4. 300-hour technical maintenance

The technical maintenance shall be carried out in accordance with the provisions of each article for 125 to 150 hours.

(2) Clean each cooling system.

(3) Adjust the travel of each joystick.

(4) Tighten the bolts and nuts of the track plates.

(5) Check the lubricating oil of the guide wheel and the idler wheel, and inspect the working condition of the floating oil seal.

(6) Filter or replace the oil used in each lubrication system of the diesel engine.

5. Disassembly, assembly and maintenance

This machine must be disassembled and maintained after working for 4,000 to 6,000 hours. After disassembly and maintenance, it is required that it can basically operate for another 4,000 to 6,000 hours. During disassembly, assembly and maintenance, refer to the structure and disassembly and assembly instructions in Chapters 2 to 6 of this manual, and follow the general mechanical disassembly and assembly procedures to inspect and measure the main components. Repair or replace them if necessary.

6. Special Maintenance

When this machine is operating in conditions with a lot of rain, water, snow and dust, as well as in extremely cold regions, in addition to strictly following the regular maintenance regulations, special attention must be paid to the inspection and maintenance of the following items:

Tighten all the oil plugs to prevent water accumulation and corrosion.

(2) Clean the machine promptly after work is completed and carefully inspect the overall condition of the machine.

(3) Pay special attention to the cleanliness of the oil filling port, utensils, grease, etc.

(4) Check whether there is any mud or water in the final drive.

(5) In damp weather, pay attention to checking whether the air filter element is clogged. If so, it should be cleaned or replaced in time.

When there is a lot of dust, the fuel filler port of the diesel engine oil pan should be cleaned every 3 to 5 days.

(7) In extremely cold conditions, appropriate diesel, lubricating oil and grease should be selected. Antifreeze should be added to the cooling water.