Piston And Connecting Rod - Kubota B1220 Workshop Manual

B1220, B1620, B1820, WSM

(3) Piston and Connecting Rod

Piston Pin Bore Internal Diameter
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.
Factory specification
Piston pin bore I.D.
Allowable limit
Oil Clearance between Piton Pin and Small End Bushing
1. Measure the piston pin O.D. 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.
Factory specification
Oil clearance between
piston pin and small end
bushing
Allowable limit
Piston pin O.D. Factory specification
Small end bushing I.D. Factory specification
Replace Small End Bushing
(A) When removing
1. Press out the used bushing using a small end bushing replacing
tool. (Refer to "SPECIAL TOOLS".)
(B) When installing
1. Clean a new small end bushing and small end hole, 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 position
of the connecting rod oil hole matches the bushing hole.
[Servicing parts dimension]
Factory specification
Oil clearance between
piston pin and small end
bushing (Spare parts)
Allowable limit
Small end bushing I.D.
Factory specification
(Spare parts)
(1) Seam
(2) Oil Hole
1-S48
ENGINE
20.000 to 20.013 mm
0.78741 to 0.78791 in.
20.05 mm
0.7894 in.
9Y1210272ENS0078US0
0.014 to 0.038 mm
0.00056 to 0.0014 in.
0.10 mm
0.0039 in.
20.002 to 20.011 mm
0.78748 to 0.78783 in.
20.025 to 20.040 mm
0.78839 to 0.78897 in.
9Y1210272ENS0079US0
0.015 to 0.075 mm
0.00059 to 0.0029 in.
0.15 mm
0.0059 in.
20.026 to 20.077 mm
0.78843 to 0.79043 in.
(A) When Removing
(B) When Installing
(a) 0.79 rad (45 °)
9Y1210272ENS0080US0
KiSC issued 07, 2011 A
(EU)