SELVA MARINE Moray 25, Service Manual

Page: 192 / 370

5-38
POWR
E
CRANKCASE, CRANKSHAFT ASSY., AND CYLINDER
BODY
2. Measure:
●
Side clearance
a
Out of specification
→
Replace the
piston and piston rings as a set.
Crankshaft inspection
1. Measure:
●
Crankshaft runout
Out of specification
→
Replace the
crankshaft.
Main-bearing oil clearance
1. Measure:
●
Main-bearing oil clearance
Out of specification
→
Replace the
bearings as a set.
Side clearance:
Top piston ring:
0.04 ~ 0.08 mm
(0.002 ~ 0.003 in)
2nd piston ring:
0.03 ~ 0.07 mm
(0.001 ~ 0.003 in)
Crankshaft runout limit:
0.03 mm (0.0012 in)
Main-bearing oil clearance:
0.012 ~ 0.044 mm
(0.0005 ~ 0.0017 in)
Measuring steps:
●
Clean the bearings, main journals, and
bearing portions of the crankcase and
cylinder body.
●
Place the cylinder body upside down
on a bench.
●
Install half of the bearings
1
and the
crankshaft 2 into the cylinder body 3 .
CAUTION:
Install the bearings in their original posi-
tions. Incorrect oil clearance measure-
ments can lead to engine damage.
NOTE:
Align each bearing projection
a
with the
notch in the cylinder body.