Kohler HD Series Service Manual page 54

Disassembly/Inspection and Service
Remove Crankshaft
Remove crankshaft.
Inspection and Service
Inspect gear teeth of crankshaft and ACR gear. If any
teeth are badly worn or chipped, or if some are missing,
replacement of crankshaft will be necessary.
Inspect crankshaft bearing surfaces for scoring,
grooving, etc. Measure running clearance between
crankshaft journals and their respective bearing bores.
Use an inside micrometer or telescoping gauge to
measure inside diameter of both bearing bores in vertical
and horizontal planes. Use an outside micrometer to
measure outside diameter of crankshaft main bearing
journals. Subtract journal diameters from their respective
bore diameters to get running clearances. Check results
against values in Specifi cations and Tolerances. If
running clearances are within specifi cation, and there
is no evidence of scoring, grooving, etc., no further
reconditioning is necessary. If bearing surfaces are worn
or damaged, crankcase and/or closure plate will need to
be replaced.
Inspect crankshaft keyway. If worn or chipped,
replacement of crankshaft will be necessary.
Inspect crankpin for score marks or metallic pickup.
Slight score marks can be cleaned with crocus cloth
soaked in oil. If wear limits in Specifi cations are
exceeded, it will be necessary to replace crankshaft.
Crankcase
Inspection and Service
Check all gasket surfaces to make sure they are free of
gasket fragments and deep scratches or nicks.
Check cylinder wall for scoring. In severe cases,
unburned fuel can dissolve lubricating oil off piston and
cylinder wall. Without lubrication, piston rings would
make metal to metal contact with wall, causing scuffi ng
and scoring. Scoring of cylinder wall can also be caused
by localized hot spots from blocked cooling fi ns or from
inadequate or contaminated lubrication.
54 KohlerEngines.com 14 690 10 Rev. --