6 Common Tips for Road Roller Maintenance!

1. Method for expelling air from fuel pipelines

One 20-ton vibratory roller was equipped with a Dongfeng Cummins diesel engine. During operation, the diesel engine stalled due to a lack of diesel in the fuel tank. After the diesel engine is turned off, although diesel is added to the fuel tank, air has already entered the diesel pipeline at this time, and it is impossible to restore fuel supply by using the hand oil pump.

To remove the air in the diesel pipeline and ensure the smooth start of the diesel engine, we adopt the following methods: First, find a small basin and fill it with a certain amount of diesel, then place it slightly higher than the hand oil pump. Secondly, remove the diesel pipe connecting the fuel tank to the hand oil pump and insert it into this small basin of diesel. Secondly, use a hand oil pump to pump diesel and completely remove the air in the low-pressure oil circuit. Finally, after reassembling the diesel pipe connecting the fuel tank to the hand oil pump and conducting a test run, the diesel engine started normally.

2. Disposal methods for damaged solenoid valves

A 20-ton vibratory roller equipped with a Dongfeng Cummins diesel engine has difficulty starting. Each time it starts, it takes a relatively long time before the diesel engine can be started with difficulty. We initially believed that the poor atomization was caused by the wear of the fuel injector, but after inspection, both the fuel injector and the fuel injection pump were found to be in good condition. When checking the start solenoid valve again, it was found that its electromagnet had no attraction.

When we remove the start solenoid valve and pull the fuel valve stem connecting the fuel injection pump and the solenoid valve by hand, the diesel engine can start smoothly. This indicates that the solenoid valve has been damaged. As new solenoid valves are temporarily unavailable in the nearby market, we have used thin copper wire to bind the fuel injection pump valve stem to prevent it from returning to its original position, and thickened the solenoid valve gasket to prevent oil leakage from the fuel injection pump valve stem hole. After the above processing, the solenoid valve was reinstalled and the roller was put into use. Just replace it after purchasing the newly started solenoid valve.

3. Repair methods for deformation of front wheel support parts

One 3Y18/21 static roller has experienced a failure to start. At that time, in order to start the road roller, a loader was used on site for top-pushing start-up. As a result, the square frame supporting the front wheel of the road roller deformed, and the welding point of the shaft sleeve where the front fork fits the vertical shaft was misaligned. Therefore, the road roller could not be used.

Usually, to fix this fault, the front wheel frame, vertical axle and front fork need to be disassembled, but this kind of repair is time-consuming and laborious. For this purpose, we adopted the following simple recovery method: First, adjust the front wheels to the forward position; Secondly, support the front wheels, the front wheel frame and the front fork crossbeam with wood to prevent the front wheels from turning when the steering wheel is turned. Secondly, turn the steering wheel. Remember the total number of turns of the steering wheel. Turn it to the limit position and then turn it back half of the total number of turns. The misaligned front fork and the shaft sleeve that fits the vertical shaft can then return to the correct position. Then, remove the 14 fixing bolts on both sides of the front wheel frame, and use a jack to lift the front wheel frame about 400mm away from the front axle. Finally, use electric welding to firmly weld the vertical shaft sleeve. Loosen the jack, lower the front wheel fork, and reassemble the front wheel frame with the front wheel shaft. This way, only one person is needed to adjust the deformation of the front wheel frame in place.

4. Repair methods for poor positioning of the gear lever

The positioning pin of the gearshift lever equipped on a static roller is prone to fall out or be cut off, thus causing the gearshift lever to fail to be positioned. This locating pin has a diameter of 4mm and is used to prevent the gearshift lever from rotating.

To solve this problem, we adopt the following methods: Firstly, expand the diameter of the pin hole of the gearshift lever to 5mm and tap the M6 internal thread; Secondly, modify the pin slot width of the gearshift lever to 6mm. Finally, configure one M6 screw and one M6 nut. Screw the screw into the seat pin hole, return it half a turn and then lock the nut.

We improved several static roller rollers according to the above-mentioned method and all achieved good results.

5. Disassembly and assembly methods for double-ended bolts

Double-ended bolts on rollers are mainly used in parts such as engine cylinder heads, fuel injectors, intake and exhaust pipes, and transmission bearing covers. The usage of a double-ended bolt is to tighten one end onto the workpiece, and then install the part on the other end and fasten it with a nut and a washer. During maintenance, when disassembling parts, only the nuts and washers need to be removed, and there is no need to disassemble the double-ended bolts. However, in actual maintenance, sometimes the double-ended bolts need to be removed together with the nuts and washers, which brings inconvenience to the disassembly work.

To solve this problem, we have made a "small tool" for disassembling and assembling double-ended bolts, which can be done simply and conveniently. The specific manufacturing method is as follows: First, prepare one hexagon bolt and two nuts with the same thread as the double-ended bolt; Secondly, screw the two nuts onto the hexagonal bolt and press the two nuts on the hexagonal bolt tightly together, ensuring they can rotate freely on the hexagonal bolt. Finally, weld the two nuts together with electric welding to form a whole. In this way, the "small tool" is completed.

The method of disassembling and assembling double-ended bolts using this "little tool" is as follows: First, screw half of the welding nut onto the double-ended bolt and the other half onto the hexagonal bolt. Secondly, use one wrench to hold the welding nut, and another wrench to tighten the hexagonal bolt and press against the end of the double-ended bolt. Finally, turn the hexagonal bolt or the welding nut to disassemble and assemble the double-ended bolt.

6. Solutions for oil leakage of sealing rings

The vibration valve of one vibratory roller was leaking oil. After replacing the Y-shaped sealing ring, oil leakage occurred again after a short period of use. The inspection found that after long-term use, the upper cover of the valve core and the valve core of the vibrating valve were severely worn.

To solve this problem, we adopt the method of adding O-shaped or flat sealing rings, that is, installing the O-shaped or flat sealing rings in the groove of the Y-shaped sealing ring. After the vibration valve was equipped with a sealing ring, no oil leakage occurred, which proves that this method has achieved good results.