Kubota WG972-E2 Workshop Manual page 129

WG972-E2, DF972-E2, WSM
Piston Ring Gap
1. Insert the piston ring into the lower part of the cylinder (the least
worn out part) with a piston ring compressor and piston.
2. Measure the ring gap with a feeler gauge.
3. If the measurement exceeds the allowable limit, replace the
piston ring.
Top ring
Piston ring gap Second ring
Oil ring
Clearance between Piston Ring and Piston Ring Groove
1. Clean the rings and the ring grooves, and install each ring in its
groove.
2. Measure the clearance between the ring and the groove with a
thickness gauge.
3. If the clearance exceeds the allowable limit, replace the piston
ring.
4. If the clearance still exceeds the allowable limit with new ring,
replace the piston.
Top ring
Second ring
Clearance between
piston ring and
piston ring groove
Oil ring
Connecting Rod Alignment
1. Remove the crankpin bearing, and install the connecting rod cap.
2. Install the piston pin in the connecting rod.
3. Install the connecting rod on the connecting rod alignment tool.
4. Put a gauge over the piston pin, and move it against the face
plate.
5. If the gauge does not fit squarely against the face plate, measure
the space between the pin of the gauge and the face plate.
6. If the measurement exceeds the allowable limit, replace the
connecting rod.
Space between gauge
Allowable limit
pin face plate
S-59
GASOLINE / LPG ENGINE
Factory 0.15 to 0.35 mm
spec. 0.0059 to 0.0138 in.
Allowable 1.25 mm
limit 0.0492 in.
Factory 0.30 to 0.45 mm
spec. 0.0118 to 0.0177 in.
Allowable 1.25 mm
limit 0.0492 in.
Factory 0.20 to 0.70 mm
spec. 0.0079 to 0.0276 in.
Allowable 1.25 mm
limit 0.0492 in.
Factory 0.080 to 0.120 mm
spec. 0.00315 to 0.00472 in.
Allowable 0.15 mm
limit 0.0059 in.
Factory 0.065 to 0.10 mm
spec. 0.0026 to 0.0039 in.
Allowable 0.15 mm
limit 0.0059 in.
0.05 mm
0.0020 in.
KiSC issued 01, 2006 A
W1146671
W1148550
W1031462