Methods to Prevent Oil Leakage in Forklifts

1.Pay attention to the effect of gaskets. Various gaskets are installed between the parts of the static parts of forklifts (such as the joint end faces, end covers, housings, cover gaskets, flat flange covers, etc.) to play a sealing role. Although the gasket is small, it has a great effect. If the material, size, manufacturing quality and installation method do not meet the technical standards, it will not play a sealing role and may even cause accidents. For example, the oil pan or valve cover is not easy to compact due to the large contact area, which can easily cause oil leakage. Oil leakage at the rear oil seal of the crankshaft will also penetrate into the clutch, which will not only waste oil, but also cause the clutch plate to be contaminated, slip and burn. Therefore, when disassembling and assembling the gasket, you should pay attention to proper placement, carefully check its quality, and install it according to the standard.

2.Tighten each nut according to the repair standard. All kinds of fastening nuts on the forklift (such as cylinder head nuts, gear chamber cover nuts and valve cover nuts) should be tightened evenly according to the specified torque. If it is too loose, the gasket will not be pressed tightly and oil will seep out; if it is too tight, the metal around the screw hole will bulge or the thread will slip and cause oil leakage. In addition, if the drain plug of the oil pan (tank shell) is not tightened or loosens and falls off, it is easy to cause a large amount of oil loss, and then a "burning tile and sticking shaft" machine damage accident will occur. 

3. Replace the failed oil seal. There are oil seals, O-rings, etc. in many moving parts of the forklift. These parts will be improperly installed, and the journal and the oil seal edge will not be concentric, which is very easy to throw oil due to deflection. Some will lose elasticity due to rubber aging after long-term use; some will lose the oil sealing effect due to damage and cracking of the lip or failure of the self-tightening spring. Therefore, if the rubber seal is found to be leaking oil, it should be corrected according to the standard or replaced with qualified accessories. 

4. Replace severely worn parts in time. Forklift parts will wear out after a certain service life. For example, when the cylinder sleeve piston connecting rod assembly, piston ring, piston and cylinder sleeve are worn to a certain extent, the high-pressure gas in the combustion chamber will flow into the crankcase; when the main shaft is replaced in time, the main bearing and the journal clearance are too large, the front and rear oil seals will lose their sealing due to the impact of the crankshaft, causing the oil to leak from the crankshaft head, or seep into the clutch, and then contaminate the friction plate and cause slipping, and the operation will fail; prevent the one-way valve and the vent valve from being blocked. This kind of valve hole is easily blocked to cause the temperature in the box shell to rise, and the oil and gas will fill the entire space and cannot be discharged, so that the pressure in the box shell will increase, and the consumption of lubricating oil will increase and the replacement cycle will be shortened. When the engine ventilation system is blocked, the movement resistance of the piston is increased, which increases fuel consumption. Due to the effect of the pressure difference between the inside and outside of the box shell, oil leakage is often caused at the weak seal. Therefore, it is necessary to regularly inspect, dredge and clean the vehicle to keep the one-way valve and vent valve unblocked. 

5. Properly handle all kinds of oil pipe joints. The sealing connecting tube nuts are often disassembled and assembled. They are easy to loosen due to thread slippage and broken buckles, which makes the accuracy of the bell mouth of the two joints worse, the contact is poor due to the non-coincidence of the center lines of the cone surfaces, and the tapers are different and inconsistent, which causes oil leakage. When replacing the connecting tube nut, the connecting tube joint and the bell mouth seal should be ground or the thin copper sheet should be clamped between the two cone surfaces, and then the nut should be tightened and compacted to ensure the seal. 

6. Prevent the wheel hub from throwing oil. During the maintenance of the wheels, the wheel hub bearing and cavity have too much lubricating grease, or the wheel hub oil seal is improperly installed, of poor quality, aging and failure, and the wheel hub temperature is too high due to frequent braking, and the half-axle nut is loose, which can cause the wheel hub to throw oil. Therefore, the vehicle maintenance should adopt the "cavity smoothing method" (i.e. proper lubrication), dredge the vents, use the brakes reasonably, strictly select high-quality accessories, and install and adjust according to the process standards to prevent the wheel hub from throwing oil.