Paccar MX-13 – Repair cylinder liner seat

This procedure describes the correct method of repairing the cylinder liner seat by machining.
The following procedure is carried out using a cylinder liner seat repair tool (1961378) i.c.w. cutting tool (1903061)

Before the tool can be used, the adjacent cylinder liner(s) must be removed.

Machining of the cylinder liner seat can only be done in two stages.
1. Stage one: Machine the cylinder liner seat until the surface is free of cavitation.
2. Stage two: Machine the cylinder liner seat until the calculated depth is reached.

1. Keep the locking bracket up and mount the cutting tool.
The serrated surface must face the electromagnet, and the centering roll must be directed towards the R on the spindle.

2. Position the tool so that it is slightly shifted from the center of the cylinder.
Make sure that the cylinder block and the tool are cleaned thoroughly.

3. Set the switch to position 1 to activate the electromagnet. Screw the vertical feed bus up so
that the cutting tool freely passes over the cylinder liner seat.

4. Press the locking bracket downwards, and place the centering roll against the wall of the cylinder liner seat, where the distance to the wall is greatest. Set the switch to position 0.

Do not set the switch in position 2.
Otherwise the magnetism fully disappears.

5. Center the unit by holding the horizontal feed bus with two fingers, and turn the handle clockwise. The unit now moves eccentrically with every revolution.
– The eccentric movement decreases and finally stops as the centering roll moves back.
– Release the horizontal feed bus at the right moment, when the centering roll is just slightly touching the counterbore wall all around.
– Rotate counterclockwise when the centering roll loses contact with the counterwall.

6. When the tool is correctly centered, set the switch to position 1.

7. Press the locking bracket downwards and position the cutting tool above the liner seat.

8. Loosen the locking screw and slowly rotate the turning handle and vertical feed bus clockwise until the cutting tool touches the seat.

9. Loosen the worm screw, set the vernier to 0 and tighten the worm screw again.

10. Press the locking bracket downwards and place the cutting tool before the seat.

11. Set the refacing depth by rotating the vertical feed bus, then tighten the locking screw. Start with 0.05 mm [0.002 in]. Do not exceed 0.15 mm [0.006 in] for the following steps.

12. Rotate the turning handle clockwise while holding the horizontal feed bus.
– Let the horizontal feed bus steadily slip between your fingers.
– Never rotate the turning handle counterclockwise. This damages the cutting tool.

13. Continue until the cutting tool has machined the entire surface.

Make sure that the entire surface is machined before setting the next depth.

14. Press the locking bracket downwards and place the cutting tool just before the seat.

15. Stage one: check if the surface of the liner seat is free of cavitation. If not, repeat steps 11 to 14.

Before the exact machining depth can be calculated, the liner seat must be free of cavitation.

16. Stage two: Continue with steps 11 to 15 until the calculated depth is reached.

17. When the calculated depth is reached, make sure that the radius R 1.2 mm [0.047 in] is machined.

18. Remove the tool.

19. Clean the cylinder block and tool thoroughly.

20. Mark the cylinder block with an L and the number of the repaired cylinder on the DMC location.


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