PISTON INSPECTION

id011000502100

Caution
•  The piston, piston pin and connecting rod (semi-floating type piston pin) cannot be disassembled.
•  When replacing the piston, piston pin, and connecting rod (semi-floating type piston pin), replace them together as a single unit.
•  If the piston, piston pin, and connecting rod of the full floating type piston pin are disassembled, the piston, piston pin, and snap ring must be replaced as a single unit.

1.  Measure the outer diameter of each piston at right angle 90° to the piston pin, 10.0 mm {0.40 in} above the under of the piston.

Semi-floating type piston pin
•  If not within the specification, replace the piston, piston pin, piston ring and connecting rod as a single unit.
Full floating type piston pin
•  If not within the specification, replace the piston, piston pin and snap ring as a single unit.
belbze00000105
Piston diameter
L8: 82.965—82.995 mm {3.2664—3.2675 in}
LF, L3: 87.465—87.495 mm {3.4435—3.4446 in}
L5: 88.965—88.995 mm {3.5026—3.5037 in}

2.  Measure the piston-to-cylinder clearance.

Semi-floating type piston pin
•  If not within the specification, replace the piston, piston pin, piston ring and connecting rod as a single unit.
Full floating type piston pin
•  If not within the specification, replace the piston, piston pin and snap ring as a single unit.
Standard clearance
0.025—0.045 mm {0.0010—0.0017 in}
Maximum clearance
0.11 mm {0.0043 in}

3.  Measure the piston ring-to-ring groove clearance around the entire circumference.

•  If it exceeds the specification, replace the piston and piston ring.
belbze00000106
Standard clearance
Top: 0.04—0.08 mm {0.0016—0.0031 in}
Second: 0.03—0.07 mm {0.0012—0.0027 in}
Oil: 0.06—0.15 mm {0.0024—0.0059 in}
Maximum clearance
Top: 0.17 mm {0.0067 in}
Second, Oil: 0.15 mm {0.0059 in}

4.  Insert the piston ring into the cylinder by hand and use the piston to push it to the bottom of the ring travel.

belbze00000107

5.  Measure each piston ring end gap with a feeler gauge.

•  If it exceeds the specification, replace the piston ring.
Standard end gap
Top
L8: 0.15—0.30 mm {0.006—0.011 in}
LF, L3: 0.16—0.31 mm {0.007—0.012 in}
L5: 0.16—0.26 mm {0.0063—0.010 in}
Second
L8: 0.32—0.47 mm {0.013—0.018 in}
LF, L3: 0.33—0.48 mm {0.013—0.018 in}
L5: 0.31—0.46 mm {0.013—0.018 in}
Oil (rail)
L5: 0.15—0.40 mm {0.006—0.015 in}
Except L5: 0.20—0.70 mm {0.0079—0.0275 in}
Maximum end gap
1.0 mm {0.0393 in}