In lawn maintenance and vegetation trimming operations, the mower has become an indispensable core tool in the era of agricultural and horticultural mechanisation, owing to its highly efficient and labour-saving advantages. However, prolonged use inevitably leads to various malfunctions. Today, Haitou Machinery provides a detailed explanation of simple repair methods for common faults, helping you swiftly restore equipment performance.
I. Insufficient engine power, resulting in poor mowing performance and even connecting rod failure
Fault manifestation:When mowing, there is a noticeable drop in power, resulting in an unevenly trimmed lawn. In severe cases, this may lead to the serious issue of a broken engine connecting rod.
Core reason:The cause lies in the deterioration of the engine oil. Following prolonged operation of the lawnmower, substantial quantities of solvent-dissolved impurities and waste products gradually accumulate within the oil. This leads to a significant decline in the oil's lubricating, cooling, and protective properties, ultimately resulting in excessive wear of the engine's internal components.
Repair Method:Regularly inspect the condition of the engine oil (observe its colour and clarity; if it appears deep black or cloudy, it must be replaced). Develop the habit of ‘frequent inspection and timely replacement’. It is recommended to change the oil to a suitable grade at intervals specified in the equipment manual.
II. Insufficient power during operation, resulting in inability to move forward or cut effectively
Fault Symptoms:
The lawn mower's speed slows down or it may even fail to move properly. When cutting the lawn, it fails to sever the grass stems, resulting in a situation where the grass is being crushed rather than cut.
Possible causes and corresponding solutions:
Severe wear on mower blades: Prolonged use causes blade edges to dull and develop nicks. Replace with new, sharp blades promptly (ensure power is off, wear protective gloves, and secure blades firmly during replacement).
Excessive lawn density: Overly dense grass growth can overload the mower. In such cases, reduce the machine's forward speed to allow sufficient cutting time for the blades. This prevents further engine damage caused by overload.
III. Failure to Start Normally After Winter Storage
Fault Symptoms:After being idle during winter, the lawn mower fails to start after multiple attempts during its first use in spring, or stalls immediately after starting.
Key Causes and Solutions:
Fuel Issues: 1. Empty fuel tank: Add fresh fuel matching the engine's specified grade. 2. Stale fuel: Fuel stored too long may degrade (winter cold can cause fuel separation and sediment buildup). Drain old fuel and refill with fresh fuel.
Carburetor Contamination: Residual fuel impurities from winter storage may clog the carburetor's internal fuel passages. This issue requires disassembly and cleaning by a professional engine maintenance technician. Do not attempt this yourself to avoid damaging carburetor components.
IV. Equipment Fails to Shut Down Properly
Fault Symptoms:After turning off the throttle switch, the lawn mower engine continues to run and cannot be shut off.
Main reasons:Poor contact or breakage of the kill switch wire. The kill switch wire is a critical component that controls engine shutdown by cutting power. Insufficient lubrication in the throttle mechanism may prevent the kill switch wire from making proper contact. Additionally, prolonged vibration can cause the kill switch wire to break.
Repair Procedure:First, apply a small amount of specialized lubricant to the throttle linkage joints to lubricate the moving parts and observe if normal operation is restored. If the engine still fails to shut off, inspect the appearance of the kill switch wire. If any signs of breakage are found, replace it with a new kill switch wire of the same model (ensure all connections are secure during replacement to prevent short circuits).
V. Abnormally Severe Vibration During Operation
Fault Symptoms:The lawn mower exhibits noticeable irregular vibrations during operation, with significant body shaking accompanied by abnormal noise, even affecting operational stability.
Troubleshooting and Resolution Methods:
Improper throttle or damper adjustment: First, check if the throttle is fully open. Excessive throttle may cause the engine to rev too high, leading to severe vibration. Reduce throttle opening as needed. Simultaneously, verify the damper position. If the damper is not in the “working position” (some equipment requires the damper open during winter startup but closed during normal operation), this may also cause vibration. Adjust the damper to the correct position.
Loose or Damaged Critical Components: If vibration persists after adjusting throttle and choke settings, possible causes include: Engine mounting bolts loose or missing (inspect all engine-to-frame mounting bolts individually and ensure they are fully tightened), or a bent engine crankshaft (a severe mechanical failure requiring immediate shutdown. Contact a professional technician for inspection and repair. Do not force operation to avoid further damage).
The above outlines the five most common issues encountered during routine lawn mower operation and their corresponding repair methods. We recommend bookmarking this guide for future reference. By implementing preventive maintenance and addressing problems promptly, you can extend the lifespan of your lawn mower and ensure efficient lawn care operations.
