Onan T260G Service Manual page 45

FIGURE 15. CHECKING RING SIDE CLEARANCE
FIGURE
14.
PISTON GROOVE CLEANING
Inspection
Follow the procedures given below when inspecting
pistons and connecting rods.
Piston Inspection:
with deep nicks, signs of fractures, scored
bores or bores out of round more than 0.002
inch.
2. Use a new piston pin to check connecting rod
for wear. A push fit clearance is required and
varies from engine to engine. If a new piston
pin falls through a dry rod pin bore as a result
of its own weight, replace the rod.
Fitting Pistons:
1.
Proper piston tolerances must be maintained
for satisfactory operation.
2.
Refer to DIMENSIONS AND CLEARANCES to
determine where to measure piston to be sure
the total clearance follows specifications.
1.
Inspect the pistons for fractures at the ring
lands, skirts, and pin bosses. Check for wear at
the ring lands using a new ring and feeler gauge
(Figure 15). Replace the piston when the side
clearance of the top compression ring reaches
0.008 inch (0.20 mm).
2.
Replace pistons showing signs of scuffing,
scoring, worn ring lands, fractures or damage
from preignition. Excessive piston wear near
the edge of the top ring land indicates
preignition.
Connecting Rod Inspection:
1.
Replace connecting rod bolts and nuts with
damaged threads. Replace connecting rods
FIGURE 16. MEASURING PISTON CLEARANCE
10-9