Onan MJA Series Service Manual page 84

82 PISTONS. CONNECTING RODS. AND CYLINDERS
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MEASURE CLEARANCE IN
DlRECTlON INOICATEiJ
8Y tlRROW
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FIG 3.8. B - CONNECTING ROD FIG 3.8. C - TOP OF PISTON
If the bushing is excessively worn, press
it
out and install a new bush­
ing. Fig 3.8. B. After installation, drill the bushing with a 3/16" drill
through the counter bored hole. in the connecting rod top. Finally, ream
the bushing to the proper size.
3.8.7 CONNECTING ROD BEARINGS
Inspect the connecting rod bearings for burrs, breaks. pitts and wear.
Measure the clearance between bearings and the crankshaft journal.
The clearance should be .001 in. to .003 in. If necessary, replace
with new standard or undersize precision bearings.
For information about the crankpin journals, see sect 3.9.5.
3.8.8 ASSEMBLY AND INSTALLA TION
1. Install the connecting rods on each piston with pins and retaining
rings. Install so the connecting rod oil spray hole is on the same
side as the "V" notch in each piston. Check rod to piston align ­
ment with an aligning fixture.
2. Install all rings on each piston. Tapered type rings will be marked
"TOP" or identified in some other manner. Place this mark toward
fl,
the closed end of the piston. Spate the ring gaps 1/3 of the way
around the piston from one another. No gap should be in line with
the piston pin. Oil the rings and pistons.
3. Position a bearing half in each connecting rod. Be sure there is nO
dirt under the bearing. This could cause high spots and early bear ­
ing failure.
4. Oil the cylinder walls. Install each piston in the proper cylinder
using a ring compressor tool. Each assembly should be installed