8. CYLINDER/PISTON MXU 300/250
SERVICE INFORMATION
GENERAL INSTRUCTIONS
· The cylinder and piston can be serviced with the engine installed in the frame.
· After disassembly, clean the removed parts and dry them with compressed air before inspection.
TROUBLESHOOTING
· When hard starting or poor performance at low speed occurs, check the crankcase breather for
white smoke. If white smoke is found, it means that the piston rings are worn, stuck or broken.
Compression too low or uneven
compression Excessive smoke from exhaust muffler
· Worn, stuck or broken piston rings · Worn or damaged piston rings
· Worn or damaged cylinder and piston · Worn or damaged cylinder and piston
Compression too high Abnormal noisy piston
· Excessive carbon build-up in combustion · Worn cylinder, piston and piston rings
chamber or on piston head · Worn piston pin hole and piston pin
8-2
Fast delivery and good communication ! The parts fit perfectly ! Thank you very much ! 
4.7 / 5