Kohler command pro CH940 Service Manual page 59

Remove Spark Plugs
Remove spark plug from each cylinder head.
Remove Valve Covers and Fuel Pump
Explosive Fuel can cause fires and severe
burns.
Do not fill fuel tank while engine is hot or
running.
Gasoline is extremely flammable and its vapors can
explode if ignited. Store gasoline only in approved
containers, in well ventilated, unoccupied buildings,
away from sparks or flames. Spilled fuel could ignite
if it comes in contact with hot parts or sparks from
ignition. Never use gasoline as a cleaning agent.
NOTE: Remove valve covers based on style of fuel
pump used.
Mechanical Fuel Pump
Mechanical fuel pump is part of valve cover and
not serviced separately. Remove with valve cover.
Disconnect fuel lines at fuel pump fittings. Properly
contain any remaining fuel.
Electric Fuel Pump
Removal will be determined based on mounted location
and application. Disconnect lead connections, fuel
line connections, and mounting hardware as required.
Properly contain any remaining fuel.
Valve Covers
1. Remove screw and grommet securing each valve
cover.
2. Remove valve cover and gasket from each cylinder
head. Note locations of individual valve covers if
they are different.
Remove Cylinder Heads and Hydraulic Lifters
NOTE: Exhaust lifters are located on output shaft side
of engine while intake lifters are located on fan
side of engine. Cylinder head number is
embossed on outside of each cylinder head.
1. Remove pipe plug from cylinder head to access
screw in upper center location.
2. Remove screws securing each cylinder head. Note
locations of washers and spacer.
3. Mark position of push rods as either intake or
exhaust and cylinder 1 or 2. Push rods should
always be reinstalled in same positions.
4. Carefully remove push rods, cylinder head and head
gasket.
5. Repeat procedure for other cylinder head.
6. Remove lifters from lifter bores. Use a hydraulic lifter
tool. Do not use a magnet to remove lifters. Mark
lifters by location, as either intake or exhaust and
cylinder 1 or 2. Hydraulic lifters should always be
reinstalled in same position.
62 690 01 Rev. J
WARNING
KohlerEngines.com
Disassembly/Inspection and Service
Inspection
Check base surface of hydraulic lifters for wear or
damage. If lifters need to be replaced, apply a liberal
coating of Kohler lubricant to base of each new lifter
before it is installed.
Bleeding Lifters Style A (Ribbed)
To prevent a possible bent push rod or broken rocker
arm, it is important to bleed any excess oil out of lifters
before they are installed.
1. Cut a 50-75 mm (2-3 in.) piece from end of an old
push rod and chuck it in a drill press.
2. Lay a rag or shop towel on table of drill press and
place lifter, open end up, on towel.
3. Lower chucked push rod until it contacts plunger in
lifter. Slowly pump plunger 2 or 3 times to force oil
out of feed hole in side of lifter.
Bleeding Lifters Style B (Smooth)
To prevent a possible bent push rod or broken rocker
arm, it is important to bleed any excess oil out of lifters
before they are installed.
1. Lay a rag or shop towel on table of drill press. Place
an 8 mm (5/16 in.) socket on towel with well end up,
then place open end of lifter on socket. Ensure
socket does not contact lifter ball surface.
2. Place some material, such as wood, plastic, or
aluminum on top of lifter to protect lifter finish.
3. Lower drill press chuck until it contacts material on
lifter. Slowly pump lifter 2 or 3 times to force oil out of
feed hole in side of lifter.
Disassemble Cylinder Heads
NOTE: These engines use valve stem seals on intake
and exhaust valves. Use a new seal whenever
valves are removed, or if seal is deteriorated in
any way. Never reuse an old seal.
1. Remove screws, rocker arm pivots, and rocker arms
from cylinder head.
2. Compress valve springs using a valve spring
compressor.
3. Once valve spring is compressed, remove following
items:
● Valve spring keepers.
● Valve spring retainers.
● Valve springs.
● Valve spring caps.
● Intake and exhaust valves (mark position).
● Valve stem seals.
4. Repeat above procedure for other cylinder head. Do
not interchange parts from one cylinder head to
another.
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