No.1 Disassemble the Spares Without Analysis
The structure of generator set is complex, so the reasons of failure are varied. If removed blindly without any analysis, the fault cannot be ruled out and may cause greater failure

NO.2 Replace Parts Blindly
It is difficult to judge and eliminate the failure of the engine. Some maintenance personnel usually replace a lot of parts. The failure didn’t rule out, and the wrong replacement parts replaced at will, increases the maintenance costs

NO.3 Didn’t Check the Fitting Clearance of Parts
There are some strict rules about the fitting clearance of engine parts, including the fitting clearance between piston and cylinder liner, piston ring, “three gap”, the tip clearance, valve clearance, plunger piston clearance, brake shoe, master-slave gear backlash clearance, bearing axial and radial clearance, valve stem and valve guide fit clearance, etc. It must be measured during the maintenance to replace or adjust the parts what does not meet the requirements of the clearance.

NO.4 Wrong Installation Way
Some parts and components have the strict requirements for the installation methods. Installed correctly is to guarantee the parts run normal. It is hard to judge whether the parts has installed in right way, because some parts can’t be distinguished the both side from the appearance.

NO.5 Incorrect Methods of Repair
When we repair generator sets, there are still a lot of maintenance personnel do not take the correct maintenance method. They use the emergency measures replace repair, which just stop the fault not rule out.