wsm wg972-e4, Руководство по ремонту

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ENGINE
WG972-E4, WSM
1-S49
(4) Piston and Connecting Rod
Piston Pin Bore I.D.
1. Measure the piston pin bore I.D. in both the horizontal and
vertical directions with a cylinder gauge.
2. If the measurement exceeds the allowable limit, replace the
piston.
9Y1211108ENS0085US0
Oil Clearance between Piston Pin and Small End Bushing
1. Measure the O.D. of the piston pin where it contacts the bushing
with an outside micrometer.
2. Measure the small end bushing I.D. with an inside micrometer,
and calculate the oil clearance.
3. If the oil clearance exceeds the allowable limit, replace the
bushing. If it still exceeds the allowable limit, replace the piston
pin.
9Y1211108ENS0086US0
Replacing Small End Bushing
(When removing)
1. Press out the used bushing using a small end bushing replacing
tool. (Refer to G-31.)
(When installing)
1. Clean a new small end bushing and bore, and apply engine oil
to them.
2. Using a small end bushing replacing tool, press in a new
bushing (service parts) taking due care to see that the
connecting rod hole matches the bushing hole.
[Servicing parts dimension]
9Y1211108ENS0087US0
Piston pin bore I.D.
Factory specification
20.000 to 20.013 mm
0.78741 to 0.78791 in.
Allowable limit
20.05 mm
0.7894 in.
Oil clearance between
piston pin and small end
bushing
Factory specification
0.012 to 0.038 mm
0.00048 to 0.0014 in.
Allowable limit
0.10 mm
0.0039 in.
Piston pin O.D. Factory specification
20.002 to 20.013 mm
0.78748 to 0.78791 in.
Small end bushing I.D. Factory specification
20.025 to 20.040 mm
0.78839 to 0.78897 in.
Oil clearance between
piston pin and small end
bushing (Spare parts)
Factory specification
0.013 to 0.075 mm
0.00052 to 0.0029 in.
Allowable limit
0.15 mm
0.0059 in.
Small end bushing I.D.
(Spare parts)
Factory specification
20.026 to 20.077 mm
0.78843 to 0.79043 in.
(1) Seam
(2) Oil Hole (A) When Removing
(B) When Installing
(a) 0.79 rad (45 °)
KiSC issued 07, 2015 A