• Direction of chisel

    Apply same direction of boom force in line with the rod and place the rod in the rock with hammering surface as vertical as possible. If hammering surface is oblique, the rod may slip during hammering. This causes the rod to seize and to be broken and piston to be damaged. When breaking, fully stabilize the rod first and then select the point of a rock on which hammering can be performed in a stable condition.

  • Direction of thrust

    Apply a thrust in a straight line with the tool. Place the tool on a rock with the hammering side as vertically as possible. If the hammering side is oblique, the tool may slip during hammering to cause the tool and piston to be broken, or seized. When breaking, select the point of a rock on which hammering can be performed stably and fully stabilize the tool to hammer.


  • Rod is deformed of burrs produced in a long-term use.
  • If the rod tip is worn out, rod is liable to slip. Grind the rod tip to sharpen the edge.
  • If the rod tip is sharpened many times, the hardened surface layer will disappear and the rod will be worn out rapidly. In this case, replace with a new rod.
  • If the gap between rod and front cover is large, the piston fails to fit in rod to cause damage to the piston or the rod.


  1. Put the breaker horizontally on the timber.
  2. Remove the spring pin or rubber plug using a pin bar.
  3. Set round bar on the opposite side, and push the stop pin with a hammer.
  4. Remove the rod pin. In removing the rod pin, be careful falling of the rod and rod pin.
  5. Wind rope or nylon sling around the rod and remove from the main body.
  6. Before installing a new rod, check wear, breakage and score. Remove burrs and swelling from the disassembled rod pin with a grinder. Excessively deformed rod pin will make replacement of rod difficult. Rod pin is required to be checked every 100 to 150 hours of operation.
  7. Grease sufficiently to inserting part of front head.