Dongfanghong bulldozer and diesel engine maintenance knowledge

I. Overview
Technical maintenance is a very important job. It is not only good for the Dongfanghong bulldozer to operate safely, but also to extend the service life. Therefore, before and after the work, the bulldozer should be inspected and maintained as required. During the operation, attention should also be paid to the occurrence of abnormalities in the operation of the bulldozer, such as noise, odor, vibration, etc., in order to timely discover the problem and solve it in time to avoid serious consequences due to the deterioration of minor faults. At the same time, technical maintenance is well done, and it can also extend the large and medium repair cycle of the bulldozer and give full play to its effectiveness. Luoyang Youjian Construction Machinery Co., Ltd. wholeheartedly serves customers.
　　
Second, the fuel system

1. The fuel for Dongfanghong Diesel engine must be selected according to the relevant regulations in the “Rules for Oil Use” and the suitable diesel oil in combination with the local working environment. The specifications and performance of diesel oil shall comply with the provisions of GB252-81 "Light Diesel".

2. The oil storage vessel should be kept clean.

3. The new oil should be treated for a long time (preferably seven days and nights), then slowly sucked out and poured into the diesel tank.

4. The diesel in the diesel engine of the bulldozer is preferably filled up immediately after the operation to prevent the gas in the tank from condensing into the oil. At the same time, the oil for the next day has a certain time to allow water and impurities to settle in the tank for removal.

5. When refueling, keep the operator's hand cleaned for oil drums, diesel tanks, fuel fillers, tools, etc. When using the pump, be careful not to draw the sediment from the bottom of the bucket.

6, when refueling. It is strictly forbidden to have a fire nearby.

7. The oil quantity should be checked frequently. If it is less than the lower limit of the oil dipstick, it must be filled.

8. The filter at the fuel filler is cleaned every 100 hours.

9. Each diesel filter should remove the sediment according to the working environment in time, but the interval should not exceed 200 hours. After the sediment is removed, the deflation should be carried out to avoid problems such as difficulty in starting and insufficient power.

Third, the cooling system

1, the use of cooling water:

(1) Distilled water, tap water, rain water or clean river water should be used as the cooling water for diesel engines. It is forbidden to use dirty water or hard water (well water, mineral water and other water with much salt) to avoid scaling and immersing the cylinder liner. Only under hard water conditions, must be softened and replenished before use.

(2) When adding water to the water tank, the cooling system may not be fully added at one time. After the diesel engine is running, it should be checked again. When it is insufficient, the foot should be added. The cooling system water inlet is located on the top of the bulldozer's small top cover.

(3) In the case of continuous operation, the cooling water should be replaced every 300 hours or so. There are five water discharge gates for the bulldozer diesel engine cooling system: 1 at the bottom of the water tank; 2 at the lower part of the diesel engine water-cooled oil cooler; 3 at the front end of the diesel engine, circulating water pump; 4 at the left front of the transfer case, on the diesel engine body; The lower end of the water outlet pipe.

2, scale treatment:

The scale of the diesel engine cooling system should be treated every 600 hours.

In the case of scale treatment, it is generally first washed with an acidic cleaning solution and then neutralized with an alkaline aqueous solution. By chemical reaction, the water-insoluble scale is converted into a salt dissolved in water and eliminated with water.

The specific operation process is as follows:

(1) Remove the thermostat of the cooling system.

(2) Start the diesel engine and raise the water temperature to 70-85C. When the floating scale is turned up, immediately turn off the fire and release the water.

(3) Inject the prepared acidic cleaning solution into the water tank, start the diesel engine, run at 600-800r/min for about 40 minutes, and extinguish the cleaning liquid.

Preparation of acidic cleaning solution:

Add three acids in clean water in the following proportions:

Hydrochloric acid: 5 to 15%

Hydrofluoric acid: 2 to 4%

Glycolic acid: 1-4%

Stir well and use.

Further, an appropriate amount of polyoxyethylene alkyl allyl ether may be added as needed to improve the permeability and dispersibility to scale. The use temperature of the acidic cleaning solution is preferably not more than 65 ° C. The preparation and use of the cleaning solution can also be carried out with reference to the relevant contents in the "135" series diesel engine service manual.

(4) Then, a 5% aqueous solution of sodium carbonate was injected to neutralize the acidic cleaning liquid remaining in the cooling system. Start the diesel engine and let it run slowly for 4 to 5 minutes, then turn off the flame to release the aqueous sodium carbonate solution.

(5) Finally, inject clean water, start the diesel engine, and make the running speed high and low. Rinse the residual solution in the cooling system with clean water, and cycle for a while to extinguish the water. According to this process, the cycle was operated several times until the discharged water was checked for neutrality with litmus paper.

(6) Within 5 to 7 days after cleaning, the cooling water should be replaced every day to prevent the residual scale from blocking the water discharge and cutting the door.

3 , the use of antifreeze:

Antifreeze can be used under severe cold and cold conditions.
　　
Fourth, the air filter

The air filter is carefully maintained according to the regulations of use, which not only prolongs the service life of the air filter, but also provides a good working condition for the diesel engine. Therefore, you should pay attention to the following items when using:

l. The engine should take out the paper filter for every 100 to 200 hours of operation. Use a method of vibrating or compressed air (pressure not greater than 0.49 MPa) to blow outward from the center of the filter or gently tap the end face. Do not use any oil or water. Cleaning.

2. Replace the new paper filter after every 1000 to 2000 hours of operation.

3. The internal safety filter should be replaced every 3000 to 4000 hours.

4. The paper filter element must be reliably sealed when installed, and must not leak or short circuit.

5. If the paper filter element is blocked by oil, water, etc., the exhaust of the engine is too thick. If the filter element cannot be improved after cleaning the filter element or the core is damaged, the new filter element should be replaced.

6. The connecting line between the air filter outlet and the diesel engine intake pipe, the connection between the air filter dust collecting chamber and the exhaust ejector rubber tube should be sealed reliably and must not leak.

7. It is strictly forbidden to remove the air filter when the diesel engine is running.
　　
Fifth, the electrical system

All kinds of components in the electrical system, especially the battery, the quality of the technical maintenance work has an important impact on the length of its service life, so it must be done in accordance with the regulations.

1 , battery :

(1) There are two 6-OA-195 dry charge batteries in the electrical system of this machine, which are used in series, and the system voltage is 24V. Each battery has a rated voltage of 12V and a 20-hour rate discharge capacity of 195A·h.

(2) First filling and use

a, the electro-hydraulic must be chemically pure sulfuric acid and distilled water, the liquid temperature should not be lower than 21 ° C (70T) or equal to 32 ° C (90F);

b. The specific gravity of the electro-hydraulic depends on the climate and temperature of the area of ​​use. The room temperature is:

30C ~ 40C electro-hydraulic specific gravity 1.270;

20 ° C ~ 30 ° C electro-hydraulic specific gravity 1.280;

The electro-hydraulic specific gravity below 20 ° C is 1.290;

c. After the battery is installed, the liquid level should be checked immediately. If the electric liquid is higher than the protection plate by 10mm, an appropriate amount of electro-hydraulic must be added.

d. Before installing the battery, if there is sufficient time, charging for 3 to 4 hours will be more favorable for the battery performance.

e. After infusion of electro-hydraulic, within 12/J', or when used, when the use time is short, or when the generator fails, it must be charged for 3 to 4 hours with a charging rate of 10 amps;

f. The effective dry time of the battery is 12 months. When it is used, if it has exceeded the effective date of the battery, it can be charged according to the above charging rate. The charging time is a large number of bubbles generated by electro-hydraulic, and the voltage and electro-hydraulic specific gravity are continuously maintained. Stable for up to 5 hours.

(3) Battery maintenance

a, the liquid level of the electro-hydraulic solution should be 10mm higher than the protective plate. During the period of use, if the liquid level is insufficient, it can only be replenished with distilled water;

b. Always tighten the liquid inlet plug and keep the battery and its surroundings dry and clean;

c. If the battery is used in a situation where it cannot be recharged, when the electro-hydraulic specific gravity drops to 1.175, it must be stopped and charged. The charging time is raised to the specified reading with the electro-hydraulic specific gravity and stabilized for three hours. ;

d. The battery to be used freely should be charged once a month;

e, end posts and wire clips can be coated with a thin layer of Vaseline to prevent corrosion.

2. Starter motor:

(1) Always check if the starter motor fastener connection is firm, the wire contact is tight, and the dirt is eliminated.

(2) Regularly check and keep the commutator clean, the brush is not stuck, and the top spring pressure is normal. If the brush wears and the commutator surface is singed, repair and replace it immediately.

(3) Check the wire insulation for damage.

3. Charging generator: The charging generator should be disassembled and maintained once every 1000 to 1500 hours of operation. The contents are as follows:

(1) Use compressed air or a leather tiger to blow off all the dust, and use gasoline to clean the collector ring and the oil on each part of the coil.

(2) Clean the bearings and replace the grease. The front and rear end caps of the charging generator are equipped with rolling bearings and are lubricated with composite calcium-based grease. The filling amount is not easy to be excessive. In particular, the amount of the back cover bearing is too large, which may cause the grease to overflow. Splashing on the slip ring will make the contact poor. , affecting the performance of the charging generator.

(3) Check the coil, rotor and rectifier components for de-soldering. If there is any disconnection or short circuit in the dry coil, the desoldering should be repaired, and if it is burnt, it should be replaced.

(4) Check the rectifier components must use a universal meter, and never use a megaohm meter (shake meter) or a power supply higher than 30V to detect. First use the "ten" test rod to take the generator's "ten" outlet head, use the "one" test stick to set up the generator "one" outlet head meter multimeter indication value should be around 40Q. If you use the "one" test stick to set up the generator "ten" outlet, use the "+" test stick to take the generator "one" outlet. Then the multimeter indication value should be above 10000Q, indicating that the rectifier component group is normal. Otherwise, it is not normal to test and develop the motor cable group and component connection lines, and measure the rectifier components one by one with a multimeter.

(5) Check the brush wear condition and whether the brush spring pressure is normal, and whether the brush holder and the outlet screw are well insulated to the ground, and the brush should be replaced if there is too much wear.

4, charging generator regulator:

(1) The charging generator regulator is a relatively sophisticated electric appliance. Do not adjust it at will. When it is confirmed that the regulator is faulty, first check the fault. Generally speaking, first check whether the contact is contaminated. The regulator spring only acts to increase or decrease the adjustment voltage data, elongate the spring, the data rises, and vice versa.

(2) The charging generator regulator shall check the data and refurbish the contacts on the special equipment every 350 working hours. FT221 relay operating voltage is 8 ~ 10V; voltage regulator half-load regulation voltage is 27 ~ 29V.

(3) When the relay contacts are separated, the gap between the armature and the iron core is 0.8~lmm, the gap between the contacts is 0.8~lmm, and the gap between the armature of the voltage regulator and the iron core is 1.4~ 1. Smm.

5, other components

Other components can be technically maintained according to the specifications of each manufacturer.

Sixth, hydraulic system

The bulldozer has three hydraulic systems, the main clutch hydraulic system, the steering hydraulic system and the work unit hydraulic system. Hydraulic system oil should be kept clean and sufficient at all times, which 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 oil level inspections. 1 is the main clutch hydraulic system fueling port, which is located in the upper part of the main clutch. 2 is the fueling port of the steering hydraulic system. It is located above the rear axle box and the driver's seat. Right side; 3 is the hydraulic port of the working device hydraulic system, located at the upper part of the outer side of the hydraulic control box. There are dipsticks 4 in the three refueling days. Can be used to view the oil level.

1. Insufficient oil level is found and the oil used is replenished in time;

2, found that the phenomenon of oil spills should be found in time to eliminate;

3. If the oil is deteriorated or dirty, replace it with new oil or discharge it for filtration.

Under normal circumstances, the oil is changed once every 800-1200 hours (the oil is changed once in the first 60 hours). When changing oil, the oil filter screen in each hydraulic system must be thoroughly cleaned. The paper filter can only be cleaned in the light diesel oil or kerosene. Do not brush it, the magnetic oil house should also be cleaned. When changing the oil in each hydraulic system, drain the dirty oil as much as possible, and carefully clean it, then add new oil according to the oil regulations.

The main clutch hydraulic system and steering hydraulic system can be drained and cleaned as usual. When the hydraulic system of the working device is drained, the bulldozer is operated to raise the blade to the highest position, then the diesel engine is turned off, the magnetic plug of the lower part of the hydraulic control box is opened to drain the oil, and finally the dozer is moved to make the blade slowly Landing, thus eliminating the residual oil in the cylinder. The oil is drained and cleaned. If the bulldozer has a ripper, the oil discharge process of the hydraulic oil in the loose earth cylinder is similar to the oil discharge process of the above-mentioned bulldozer cylinder.

Refuel with a special funnel that is carried randomly, and then add the oil to make the diesel engine run at a low speed. Repeat the lifting of the blade 3 to 5 times, and then refill the fuel tank of each hydraulic system until the liquid level reaches the required liquid level.
　
Seven, regular maintenance
　　
1 , 8-10 hours technical maintenance:

(1) Before work:

a. According to the relevant regulations in this manual, add oil or grease to each fuel tank and lubrication point according to the quantity.

b. Fill up the cooling water.

c. Whether the nut, etc. are loose or missing, if any, tighten and fill.

d. Check whether the joysticks are flexible and reliable, and whether the stroke is normal.

e. Check the exhaust of the diesel engine, whether the sound is normal, and whether there is leakage.

f. Check whether the various instruments work normally, and abnormal phenomena are eliminated in time.

g. If any parts have oil leakage or abnormal noise, remove them in time.

h. Remove dust from the air filter dust cup.

(2) After work:

a. Clean all parts and check for any loss, damage or leakage.

b. Add diesel fuel to the diesel tank.

c. Cool the water in summer, or put cooling water or antifreeze in winter or cold areas.

d. Stored properly.

2 , 60 hours technical maintenance:

(1) Execute each piece of technical maintenance for 8-10 hours.

(2) Adjust the tightness of the fan belt.

(3) Check the liquid level and density of the battery electrolyte, and replenish or charge when not enough.

(4) Check the electrical system for short circuits, open circuits, and damage.

(5) Check the operation of the transmission system and the oil level. If there is any fault, it should be eliminated. If there is no oil, it should be made up.

(6) Check the tension of the track and adjust if necessary.

(7) Remove the dirt from the diesel oil sump and check the oil level.

(8) Check the oil level of each hydraulic system and add oil. When the new machine is used, it should be changed.

3 , 125-150 hours technical maintenance:

(1) Conducted in accordance with each section of technical maintenance for 60 hours.

(2) Clean each filter element.

(3) Replace all cooling water.

(4) Adjust the fan belt.

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

(6) Check the oil level of each part of the transmission system and refuel if necessary.

(7) Check the oil level of the hydraulic control box and refuel if necessary.
　　
4 , 300 hours technical maintenance:

(1) The regulations for each of the 125-150 hours of technical maintenance are carried out.

(2) Clean up each cooling system.

(3) Adjust the stroke of each joystick.

(4) Tighten the track shoe bolts and nuts.

(5) Check the lubricating oil of the guide wheel and the sprocket wheel to check the working condition of the floating oil seal.

(6) The lubricating system of the diesel engine is filtered or replaced with oil.

5 , disassembly and maintenance:

After the machine is operated for 4,000 to 6,000 hours, it must be disassembled and maintained. After disassembly and maintenance, the requirements can basically reach the level of 4000 to 6000 hours. In the disassembly and maintenance, refer to the structure and disassembly instructions in Chapters 2 to 6 of this manual, and inspect and measure the main parts according to the general mechanical disassembly procedure, and repair or replace if necessary.

6 , special maintenance:

This machine must pay special attention to the inspection and maintenance of the following items in addition to the regular maintenance regulations when working in rain, water, snow, dust and working conditions in severe cold areas:

(1) Tighten the oil plugs everywhere to prevent corrosion.

(2) Clean the work in time and carefully check the condition of the whole machine.

(3) Pay special attention to the cleaning of fuel fillers, utensils, grease, etc.

(4) Check if the final drive is muddy.

(5) Wet weather Pay attention to check whether the air filter element is clogged. If it is, it should be cleaned or replaced in time.

(6) When there is a lot of dust, clean the fuel filler of the diesel engine oil sump every 3 to 5 days.

(7) Under severe cold conditions, choose the right diesel, lubricating oil and grease. Antifreeze should be added to the cooling water. Check the battery at any time