Kohler command pro CH742 Service Manual page 51

Remove Oil Pump (Style B)
Oil pump is mounted inside closure plate. If service
is required, refer to Disassembly, Inspection, and
Reassembly.
Disassembly
1. Remove screws.
2. Lift oil pump assembly from closure plate. Remove
outer gerotor gear from closure plate.
3. Ensure ball and spring remain installed in pressure
relief hole of closure plate. If ball and spring fall out
of pressure relief hole, see reassembly for correct
installation.
4. Remove oil pump cover O-ring from groove in
closure plate.
Inspection
Inspect oil pump housing, gear, and rotors for nicks,
burrs, wear, or any visible damage. Inspect oil pump
cover O-ring for cuts, nicks, or any visible damage. If any
parts are worn or damaged, replace oil pump assembly
and/or O-ring. Check oil pickup screen for damage or
restriction, replace if necessary.
Reassembly
1. Lubricate outer gerotor gear with oil. Install outer
gerotor gear through shaft of oil pump, around inner
gerotor gear. Matching molding dots on inner and
outer gerotor gears is not necessary and will not
affect oil pump effi ciency.
2. Reinstall ball, then spring into pressure relief hole in
closure plate.
3. Reinstall O-ring into groove in closure plate; make
sure it is fully seated in groove.
3. Install oil pump inserting center shaft into
corresponding recess in closure plate. Apply
consistent downward pressure to oil pump cover,
compressing oil pressure relief spring and start
screws. Secure oil pump by torquing screws (in no
specifi c sequence) to 9.0 N·m (80 in. lb.).
4. After torquing, rotate gear and check for freedom of
movement. Make sure there is no binding. If binding
occurs, loosen screws, reposition pump, retorque
screws and recheck movement.
Remove Camshaft
Remove camshaft.
Inspection and Service
NOTE: To prevent repeat failures, camshaft and
crankshaft should always be replaced as a set.
Check lobes of camshaft for wear or damage. See
Specifi cations for minimum lift tolerance. Inspect
cam gear for badly worn, chipped or missing teeth.
Replacement of camshaft will be necessary if any of
these conditions exist.
24 690 34 Rev. D
Disassembly/Inspection and Service
Remove Connecting Rods with Pistons and Rings
NOTE: If a carbon ridge is present at top of either
cylinder bore, use a ridge reamer tool to remove
ridge before attempting to remove piston.
NOTE: Cylinders are numbered on crankcase. Use
numbers to mark each end cap, connecting rod
and piston for reassembly. Do not mix end caps
and connecting rods.
1. Remove screws securing closest connecting rod end
cap. Remove end cap.
2. Carefully remove connecting rod and piston
assembly from cylinder bore.
3. Repeat above procedures for other connecting rod
and piston assembly.
Piston and Rings
Piston and Rings Components and Details
A
Middle Compression
C
E Expander
KohlerEngines.com
A
B
C
D
F
E
Top Compression
Piston B
D
Ring
Oil Control Ring
F
Ring
Rails
(3 Piece)
51