Kohler XT775 [44/56] Disassembly inspection and service

Disassembly/Inspection and Service

KohlerEngines.com 14 690 01 Rev. G

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 Specications and Tolerances. If

running clearances are within speci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 Speci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 scufng

and scoring. Scoring of cylinder wall can also be caused

by localized hot spots from blocked cooling ns or from

inadequate or contaminated lubrication.