5. To install a new pin, the proper fork inserts must be in place to support the rod.
6. Position the rod inside the piston. Insert the proper pin guide through one side of the piston and through the
rod. Hand tap the pin guide so it is held by the piston. Insert the new pin into the piston from the other side
and set the assembly into the support fixture with the pin guide facing down.
The pin guide should be centered on the connecting rod through the piston. If assembled correctly, the
pin guide will sit exactly under the center of the hole in the tool's arch, and rest evenly on the fork inserts.
If the wrong size pin guide is used, the piston and pin will not up with the support fixture.
7. Insert the installer tool through the hole in the arch of the support fixture and use an hydraulic press to force
the piston pin through the rod little end. Continue pressing until the pin guide falls free and the installer tool
seats against the top of the arch.
Do not exceed 1250 ± 500 kg (2765 ± 1100 lb) of force when the installing tool seats angainst the top of
the arch.
INSPECTION
Pistons and Piston Pins
1. Check each piston for scuffing, scoring, wear and other defects. Replace any piston that is defective.
2. Check each piston ring for breakage, damage and abnormal wear. Replace the defective rings. When the
piston requires replacement, its rings should also be replaced.
3. Check that the piston pin fits in the piston pin hole. Replace any piston and pin assembly that is defective. The
piston pin must be pressed smoothly by hand into the pin hole (at room temperature).
Piston Rings
1. Measure the piston ring side clearance. If the measured value exceeds the service limit, insert a new ring in
the ring groove to measure the side clearance. If the clearance still exceeds the service limit, replace the
piston and rings together. If it is less than the service limit, replace only the piston rings.
Piston ring side clearance
No.1 : 0.04 ~ 0.08mm (0.0016 ~ 0.0031in.)
No.2 : 0.03 ~ 0.07mm (0.0012 ~ 0.0028in.)
[Limit]
No.1 : 0.1 mm (0.004 in.)
No.1 : 0.1 mm (0.004 in.)
2. To measure the piston ring end gap, insert a piston ring into the cylinder bore. Position the ring at right angles
to the cylinder wall by gently pressing it down with a piston. Measure the gap with a feeler gauge. If the gap
exceeds the service limit, replace the piston ring.
Piston ring end gap
Page 2 of 6
24.04.2008
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