Aerial work platform is to restore the mechanical properties of engineering technology, maintenance, troubleshooting and eliminate hidden troubles, effective means of extending the service life of the machines. The current domestic automobile maintenance industry has a considerable scale, and maintenance of engineering machinery industry started relatively late, in the maintenance has many technical problems. These problems lead to mechanical maintenance quality is not high, the equipment reliability is poor, so that consumers suffer losses, even major engineering machinery accident. The author makes a brief analysis on the common technical problems encountered in the engineering machinery maintenance work, to draw attention to the staff.

1. Can not correctly judge the fault analysis, blind dismounting phenomenon It is quite common for. Some maintenance personnel due to the unclear on the structure and principle of engineering machinery, without a careful analysis of the fault reason, can not accurately determine the fault position, with "probably, almost" blind thought of mechanical dismounting, not only the results of the original fault has not ruled out, but due to poor maintenance skills and technology, and the emergence of new problems. 1 sets of Nissan Diesel Power Komatsu bulldozer, appeared unable to work, lack of mechanical failure, maintenance personnel and disassemble the PT fuel injection pump and injector also did not find fault reasons, the replacement of the 1 fuel injection pump test, the fault is still. Finally, check the fault is used due to the impurities, internal water caused by excessive diesel, and the disassembly can cause the performance of the PT injection pump decreased significantly, the diesel engine power shortage. Therefore, when the mechanical failure, should be tested by testing equipment, such as testing equipment, through the fault diagnosis methods and means, check, test, ask to see "the tradition, combined with the structure and working principle of engineering machinery, to determine the most likely failure of the site. In determining the fault of construction machinery, the commonly used "exclusion" and "comparison method", follow from simple to complex, first appearance after the first assembly and parts, internal order, avoid "without forethought, blind dismounting".
2. Blind replacement parts, a "replacement and repair" phenomenon exists. Troubleshooting and mechanical engineering judgment is relatively difficult, some maintenance personnel with a consistent method of test, no matter large small pieces, as long as that may be the cause of the fault components, a replacement test, the result not only failure is not ruled out, and the replacement of parts replaced, an increase in consumer spending. Due to difficulties, to a factory maintenance, replacement of the vane pump manufacturers (steering pump), relief valve, steering cylinder and other parts are of no avail, found the cause of the malfunction to the internal steering vane pump of a hydraulic oil and hydraulic oil rubber aging, resulting in insufficient fluid flow and pressure. Some parts can be repaired to restore fault through its technical properties, such as generator, starter, oil cooler, oil pump gear failure, do not need complex repair technology can repair, but the maintenance staff but requires the user to replace the new thing, just take the method of "replacement and repair", causing serious waste. The blind change test and blindly repair parts replacement practices in some repair units also exist to varying degrees. In maintenance, should be based on a careful analysis of the fault phenomena and location to determine the cause of the malfunction, can repair parts to repair method to restore the technical performance, eliminate blind replacement parts approach.
3. Do not check for new quality, the more common failure problems after assembly. In the replacement of parts, some maintenance personnel do not check for new parts, used directly after installation in construction machinery, this kind of practice is not scientific. Spare parts currently on the market are not bad quality, some fake fish and some accessories; accessories inventory for too long, the performance changes, without detection, often caused by failure after assembly. Diesel engine oil cooler oil cracking, causing water to replace a new oil cooler, starting test machine, still water in the oil, and examined the other components, fault reason not found. After open the new oil cooler cover, found oil sealing ring at the side cover without compaction, causes the oil and water mix, the reason is the quality of oil cooler.