Kohler Command PRO CH270, Service Manual

Page: 89 / 126

10.3
Section 10
Inspection and Reconditioning
10
Figure 10-5. Camshaft Journal Checking.
Camshaft Journal Specifi cations
Engine Model Dimension Limit
CH270
13.975 mm
(0.5500 in.)
13.900 mm
(0.5470 in.)
CH395, CH440
15.975 mm
(0.6289 in.)
15.900 mm
(0.6260 in.)
Crankshaft
Inspection and Service
Inspect the gear teeth of the cranksha ft . If the teeth
are badly worn, chipped, or some are missing,
replacement of the cranksha
ft will be necessary.
Inspect the cranksha ft bearing surfaces for scoring,
grooving, etc. Measure the running clearance between
the cranksha
ft journals and their respective bearing
bores. Use an inside micrometer or telescoping gauge
to measure the inside diameter of both bearing bores
in the vertical and horizontal planes. Use an outside
micrometer to measure the outside diameter of the
cranksha
ft main bearing journals. Subtract the journal
diameters from their respective bore diameters to get
the running clearances. Check the results against the
values in Section 1,
Speci fi cations and Tolerances .
If the running clearances are within speci fi cation,
and there is no evidence of scoring, grooving, etc.,
no further reconditioning is necessary. If the bearing
surfaces are worn or damaged, the crankcase and/or
closure plate will need to be replaced.
Inspect the cranksha ft keyways. If worn or chipped,
replacement of the cranksha ft will be necessary.
Inspect the crankpin for score marks or metallic
pickup. Slight score marks can be cleaned with crocus
cloth soaked in oil. If wear limits, as stated in Section
1,
Speci fi cations and Tolerances are exceeded, it will
be necessary to replace the cranksha ft .
B
Figure 10-4. Cam Lobe Checking B.
Cam Lobe Dimension B
Engine
Model
Valve Dimension B Service Limit
CH270
INTAKE
22.200 mm
(0.8740 in.)
21.582 mm
(0.8497 in.)
EXHAUST
22.200 mm
(0.8740 in.)
21.582 mm
(0.8497 in.)
CH395
INTAKE
26.060 mm
(1.0260 in.)
25.440 mm
(1.0044 in.)
EXHAUST
26.060 mm
(1.0260 in.)
25.440 mm
(1.0044 in.)
CH440
INTAKE
26.092 mm
(1.0272 in.)
25.041 mm
(0.9859 in.)
EXHAUST
26.000 mm
(1.0236 in.)
24.970 mm
(0.9831 in.)
Measure the camsha ft journals, which fi t in the ball
bearings, for wear using a micrometer. Compare with
speci
fi cations listed. See Figure 10-5.
CH440 Cam Lobe Dimension A
Valve Dimension A Service Limit
INTAKE
32.266 mm
(1.3097 in.)
32.642 mm
(1.2851 in.)
EXHAUST
32.260 mm
(1.2701 in.)
31.610 mm
(1.2445 in.)