During construction operations, the hydraulic system of a skid-steer loader is like the "heart" of the machine. A failure directly impacts core functions 

like lifting and tilting, slowing construction progress. This article, using the LEAD series skid-steer loader as an example, analyzes common causes of 

hydraulic system failures and provides targeted solutions.

I. Analysis of Hydraulic System Failure Causes

(I) Hydraulic Oil-Related Issues

Hydraulic oil is the "blood" of the hydraulic system, and its condition directly impacts system operation. A low hydraulic oil level in a LEAD series skid-steer 

loader can lead to insufficient oil suction from the hydraulic pump, preventing system pressure from building, and causing sluggish or even inoperative 

operation. Furthermore, if the hydraulic oil is not replaced or becomes contaminated over time, impurities in the oil can wear out components like the 

hydraulic pump and valves, and can also clog filters, hindering proper flow of hydraulic oil. For example, if the hydraulic system is not cleaned and 

maintained promptly after work on a dusty construction site, dust can easily mix into the hydraulic oil, causing contamination.

(II) Pipeline and Cylinder Leaks

The hydraulic hoses and cylinders of a LEAD series skid-steer loader are key components of the high-pressure oil circuit. Long-term operation under 

complex working conditions can cause cracks in hoses due to aging and wear, and wear in cylinder seals due to frequent expansion and contraction. 

These can all lead to hydraulic oil leaks. Leaks not only reduce system pressure, but also waste fluid and pollute the work environment. For example, 

during municipal road maintenance, a cylinder leak can cause hydraulic oil to drip onto the road surface, creating both an aesthetically pleasing and safety hazard.

(III) Hydraulic Pump or Valve Failure

The hydraulic pump is the power source of the hydraulic system, while the valve controls the flow and pressure of the hydraulic oil. If the hydraulic 

pump of a LEAD series skid-steer loader wears out due to long-term high-load operation, it can increase internal clearances in the pump body, reduce 

volumetric efficiency, and result in insufficient output pressure. If the valve becomes stuck or worn, it can cause hydraulic oil control failure. For example, 

a stuck reversing valve can prevent the equipment from switching properly, affecting operational continuity.

II. Targeted Solutions for the LEAD Series

(I) Hydraulic Oil Maintenance Plan

Regularly check the hydraulic oil level in the LEAD series skid-steer loader to ensure it is within the specified range. If the level is low, promptly add a 

qualified hydraulic oil of the same type. At the same time, strictly follow the hydraulic oil replacement schedule specified in the equipment maintenance 

manual. It is generally recommended to replace the oil approximately every 500 hours of operation. When replacing the oil, thoroughly clean the 

hydraulic oil tank and related lines to prevent contamination of the new oil. Additionally, before daily operations, the hydraulic oil's appearance and 

odor can be used to initially assess its condition. If the oil is cloudy or has an odor, it should be replaced promptly.

(II) Pipeline and Cylinder Inspection and Maintenance Plan

Establish a regular inspection system for the pipelines and cylinders of the LEAD series skid-steer loaders. Carefully inspect hoses for cracks and 

bulges, and cylinders for signs of oil leakage before and after operations. If hoses are damaged, promptly replace them with high-pressure hoses 

that meet specifications. For cylinder leaks, disassemble the cylinder and replace worn seals. When replacing components, ensure proper installation 

to prevent further leaks caused by improper installation.

(III) Hydraulic Pump and Valve Repair Plan

When a hydraulic pump or valve failure occurs in a LEAD series skid-steer loader, first conduct a professional inspection to determine the specific 

location of the problem. If a hydraulic pump is worn, repairs can be performed based on the severity of the wear, such as grinding the pump body 

and replacing worn parts. If the wear is severe and cannot be repaired, the pump should be replaced. For valve failures, if the problem is sticking, 

the valve can be cleaned and lubricated; if the problem is wear, the corresponding valve components should be replaced. Furthermore, avoid 

overloading the equipment during operation to extend the service life of the hydraulic pump and valves.

The LEAD series skid steer loaders effectively ensure stable hydraulic system operation through scientific troubleshooting and targeted solutions, 

allowing the equipment to continue to perform efficiently in various construction operations, safeguarding construction efficiency and quality.