Seven common misunderstandings in the maintenance and repair of road rollers: Everyone must pay attention in daily life!

1. Heat the piston with an open flame

When the piston is directly heated by an open flame, the thickness of each part of the piston is uneven, and the degree of thermal expansion and contraction is different, which is prone to deformation. If it reaches a certain high temperature and cools naturally, the metal structure will be damaged, reducing its wear resistance and greatly shortening its service life.

2. Sand the bearing bush with sandpaper

Many maintenance workers use sandpaper to polish the bearing shells in order to increase the contact surface between the bearing shells and the shaft. However, due to the hardness of the sand grains and the softness of the alloy, the sand grains can easily embed into the alloy during grinding, accelerating the wear of the bearing shells when the engine is running and shortening the service life of the crankshaft.

3. The engine oil is only added and not changed

There are many mechanical impurities remaining in the used oil. Even if it is completely drained, impurities still remain in the oil pan and oil passage.

4. Misuse and random application of grease

Some road roller repairmen like to apply a layer of grease on the cylinder gasket when installing it. The cylinder gasket not only needs to strictly seal the high-temperature and high-pressure gas generated inside the cylinder, but also needs to seal the cooling water and engine oil with certain pressure and flow rate in the cylinder head and cylinder body. When applying grease on the cylinder gasket and the cylinder head bolts are tightened, Some of the grease will be squeezed into the water and oil passages of the cylinder. The grease remaining between the cylinder gaskets is prone to impact this area by high-temperature and high-pressure gas during the operation of the cylinder, damaging the gasket and causing gas leakage. In addition, if the grease is exposed to high temperatures for a long time, carbon deposits will form, causing the cylinder gasket to age and deteriorate prematurely

5. The bolts are tightened too much

Excessive preload can cause screws and bolts to break or threads to slip, etc.

6. The tire pressure is too high

Both excessively high and low tire pressure can affect their service life and are also detrimental to safe driving.

7. When the water tank boils, suddenly add cold water

Suddenly adding cold water, due to the excessive temperature difference, will cause the cylinder head and cylinder block to "crack". Therefore, once the radiator "boils over" is found during use, emergency measures should be taken to ensure that the engine cooling water cools down by itself.