Kohler Command PRO CH940 User manual

CH940-CH1000
Service Manual
KohlerEngines.com
IMPORTANT: Read all safety precautions and instructions carefully before operating equipment. Refer to operating
instruction of equipment that this engine powers.
Ensure engine is stopped and level before performing any maintenance or service.
62 690 01 Rev. J 1
2 Safety
3 Maintenance
5Specications
21 Tools and Aids
24 Troubleshooting
28 Air Cleaner/Intake
29 Fuel System
35 Governor System
36 Lubrication System
38 Electrical System
49 Starter System
53 Disassembly/Inspection and Service
69 Reassembly

Safety
262 690 01 Rev. JKohlerEngines.com
SAFETY PRECAUTIONS
WARNING: A hazard that could result in death, serious injury, or substantial property damage.
CAUTION: A hazard that could result in minor personal injury or property damage.
NOTE: is used to notify people of important installation, operation, or maintenance information.
WARNING
Explosive Fuel can cause
res and severe burns.
Do not ll fuel tank while
engine is hot or running.
Gasoline is extremely ammable
and its vapors can explode if
ignited. Store gasoline only in
approved containers, in well
ventilated, unoccupied buildings,
away from sparks or ames.
Spilled fuel could ignite if it comes
in contact with hot parts or sparks
from ignition. Never use gasoline
as a cleaning agent.
WARNING
Rotating Parts can cause
severe injury.
Stay away while engine
is in operation.
Keep hands, feet, hair, and
clothing away from all moving
parts to prevent injury. Never
operate engine with covers,
shrouds, or guards removed.
WARNING
Carbon Monoxide can
cause severe nausea,
fainting or death.
Avoid inhaling exhaust
fumes.
Engine exhaust gases contain
poisonous carbon monoxide.
Carbon monoxide is odorless,
colorless, and can cause death if
inhaled.
WARNING
Accidental Starts can
cause severe injury or
death.
Disconnect and ground
spark plug lead(s) before
servicing.
Before working on engine or
equipment, disable engine as
follows: 1) Disconnect spark plug
lead(s). 2) Disconnect negative (–)
battery cable from battery.
WARNING
Hot Parts can cause
severe burns.
Do not touch engine
while operating or just
after stopping.
Never operate engine with heat
shields or guards removed.
WARNING
Cleaning Solvents can
cause severe injury or
death.
Use only in well
ventilated areas away
from ignition sources.
Carburetor cleaners and solvents
are extremely ammable. Follow
cleaner manufacturer’s warnings
and instructions on its proper and
safe use. Never use gasoline as a
cleaning agent.
CAUTION
Electrical Shock can
cause injury.
Do not touch wires while
engine is running.
CAUTION
Damaging Crankshaft
and Flywheel Can cause
personal injury.
Using improper procedures can
lead to broken fragments. Broken
fragments could be thrown from
engine. Always observe and use
precautions and procedures when
installing ywheel.
CAUTION
Failure to utilize or
reassemble debris
screen as designed could
result in debris screen
failure and serious
personal injury.

Maintenance
362 690 01 Rev. J KohlerEngines.com
MAINTENANCE INSTRUCTIONS
WARNING
Before working on engine or equipment, disable engine as
follows: 1) Disconnect spark plug lead(s). 2) Disconnect
negative (–) battery cable from battery.
Accidental Starts can cause severe injury or
death.
Disconnect and ground spark plug lead(s)
before servicing.
Normal maintenance, replacement or repair of emission control devices and systems may be performed by any repair
establishment or individual; however, warranty repairs must be performed by a Kohler authorized dealer.
MAINTENANCE SCHEDULE
Weekly
● Check lter minder. Air Cleaner/Intake
Every 25 Hours or Annually¹
● Service/replace low-prole precleaner. Air Cleaner/Intake
Every 100 Hours or Annually¹
● Change oil. Oil lter is recommended. Lubrication System
Every 150 Hours¹
● Replace low-prole air cleaner element. Air Cleaner/Intake
● Remove cooling shrouds and clean cooling areas. Air Cleaner/Intake
Every 150 Hours
● Check heavy-duty air cleaner element. Air Cleaner/Intake
● Replace fuel lter.
● Check oil cooler ns, clean as necessary. Lubrication System
Every 200 Hours
● Change oil lter. Lubrication System
Every 300 Hours
● Replace heavy-duty air cleaner element. Air Cleaner/Intake
Every 500 Hours or Annually¹
● Replace spark plugs and set gap. Electrical System
Every 500 Hours²
● Have crankshaft splines lubricated.
Every 600 Hours
● Replace heavy-duty inner air cleaner element. Air Cleaner/Intake
1Perform these procedures more frequently under severe, dusty, dirty conditions.
2Have a Kohler authorized dealer perform this service.
REPAIRS/SERVICE PARTS
Kohler genuine service parts can be purchased from Kohler authorized dealers. To nd a local Kohler authorized
dealer visit KohlerEngines.com or call 1-800-544-2444 (U.S. and Canada).

Maintenance
462 690 01 Rev. JKohlerEngines.com
OIL RECOMMENDATIONS
We recommend use of Kohler oils for best performance.
Other high-quality detergent oils (including synthetic)
of API (American Petroleum Institute) service class SJ
or higher are acceptable. Select viscosity based on
air temperature at time of operation as shown in table
below.
°F -20 020324060
50 80 100
°C -30 -20 -10 0 10 20 30 40
75
10W-30
5W-30
SAE 30
20W-50
FUEL RECOMMENDATIONS
WARNING
Explosive Fuel can cause res and severe
burns.
Do not ll fuel tank while engine is hot or
running.
Gasoline is extremely ammable and its vapors can
explode if ignited. Store gasoline only in approved
containers, in well ventilated, unoccupied buildings,
away from sparks or ames. Spilled fuel could ignite
if it comes in contact with hot parts or sparks from
ignition. Never use gasoline as a cleaning agent.
NOTE: E15, E20 and E85 are NOT approved and
should NOT be used; effects of old, stale or
contaminated fuel are not warrantable.
Fuel must meet these requirements:
● Clean, fresh, unleaded gasoline.
● Octane rating of 87 (R+M)/2 or higher.
● Research Octane Number (RON) 90 octane minimum.
● Gasoline up to 10% ethyl alcohol, 90% unleaded is
acceptable.
● Methyl Tertiary Butyl Ether (MTBE) and unleaded
gasoline blend (max 15% MTBE by volume) are
approved.
● Do not add oil to gasoline.
● Do not overll fuel tank.
● Do not use gasoline older than 30 days.
STORAGE
If engine will be out of service for 2 months or more
follow procedure below.
1. Add Kohler PRO Series fuel treatment or equivalent
to fuel tank. Run engine 2-3 minutes to get stabilized
fuel into fuel system (failures due to untreated fuel
are not warrantable).
2. Change oil while engine is still warm from operation.
Remove spark plug(s) and pour about 1 oz. of
engine oil into cylinder(s). Replace spark plug(s) and
crank engine slowly to distribute oil.
3. Disconnect negative (–) battery cable.
4. Store engine in a clean, dry place.

Specications
562 690 01 Rev. J KohlerEngines.com
Engine Dimensions with Heavy-Duty Air Cleaner - Flywheel Side
A484.3 mm (19.07 in.) B
135.0 mm (5.32 in.)
Rain Cap Cover
Removal
C365.5 mm (14.39 in.) D
130.0 mm (5.12 in.)
Air Filter Cover
Removal
E74.0 mm (2.91 in.) FChoke Control GThrottle Control HMechanical Fuel
Pump
I698.6 mm
(27.50 in.) J5.4 mm (0.21 in.) Spark Plug Lead KSupply Fuel Filter LEngine Mounting Surface
M
8 X 10.3 mm
(0.40 in.)
Thru Mounting Holes
NCenter Line Engine O232.0 mm (9.13 in.) P106.0 mm (4.17 in.)
QMounting Hole "A" R136.2 mm (5.36 in.) S14.7 mm (0.58 in.)
Spark Plug Lead T
328.3 mm
(12.93 in.)
Air Filter Element
Removal
UOil Fill
A
C
E
D
B
GF
U
T
S
R
Q
P
O
M
N
L
K
J
H
I

Specications
662 690 01 Rev. JKohlerEngines.com
Engine Dimensions with Heavy-Duty Air Cleaner - PTO Side
A427.8 mm (16.84 in.) B107.9 mm (4.25 in.) C35° D30°
EOil Level Dipstick F45° G60.0 mm (2.37 in.)
Exhaust Port H340.8 mm (13.42 in.)
ISolenoid Shift Starter JMounting Hole "A" KRotation Direction L177.8 mm (7.0 in.)
Optional Pilot
M
M8 X 1.25 mm-6H in.
25 mm (0.98 in.)
Deep on a Ø 254 mm
(10.0 in.) B.C.
N
4 X 7/16-14 UNC-2B in.
21 mm (0.83 in.) Deep
on a Ø 142.9 mm
(5.63 in.) B.C.
O
4 X 3/8-16 UNC-2B in.
17 mm (0.67 in.) Deep
on a Ø 196.9 mm
(7.750 in.) B.C.
P2 X 35.0 mm (1.38 in.)
Gasket
Q4 X M8 X 1.25 mm
Studs
A
B
CC
DD
E
FF
Q
P
G
G
H
I
JK
FF
L
M
N
O

Specications
762 690 01 Rev. J KohlerEngines.com
Engine Dimensions with Heavy-Duty Air Cleaner - Starter Side
A
422.7 mm (16.64 in.)
Cylinder #1 Shroud
Removed
B
4 X 47.3 mm (1.86 in.)
Air Cleaner Clip
Clearance
CPTO Mounting
Surface D105.3 mm (4.14 in.) Exhaust Port #1
E192.3 mm (7.57 in.) FMufer (Optional) G460.0 mm (18.11
in.) H9.5 mm (0.38 in.) SQ. Keyway
I36.5 mm (1.44 in.) J155.6 mm (6.13 in.) K5/8-18 UNF-2B in.
38.1 mm (1.5 in.) Deep L113.2 mm (4.46 in.)
MEngine Mounting
Surface NOil Drain Plug 1/2 NPT Inch O435.0 mm (17.13 in.) P401.8 mm (15.82 in.)
Q135.0 mm (5.3 in.) R119.0 mm (4.69 in.) S16.0 mm (0.63 in.) TGrass Screen
UMounting Hole "A" V570.8 mm (22.47 in.) W50.0 mm (1.97 in.)
Oil Filter Removal XCylinder #1 Shroud
A
B
X
W
V
U
T
O
P
Q
R
S
C
N
M
LJ
G
K
I
H
FE
D
C

Specications
862 690 01 Rev. JKohlerEngines.com
Engine Dimensions with Heavy-Duty Air Cleaner - Opposite Starter Side
A
422.7 mm (16.64 in.)
Cylinder #2 Shroud
Removed
BLifting Point CCylinder #2 Shroud DAccess to Oil Cooler
EFuel Filter FMounting Hole "A" G16.0 mm (0.63 in.) H119.0 mm (4.69 in.)
I135.0 mm (5.32 in.) J239.5 mm (9.43 in.) KOil Drain Plug
1/2 NPT Inch LEngine Mounting Surface
M4 X 4.0 mm (0.16 in.)
Pilot Height NPTO Mounting Surface OPilot Surface POil Pressure Switch
Q82.3 mm (3.24 in.)
Exhaust Port #2
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
O
N
P
B
Q

Specications
962 690 01 Rev. J KohlerEngines.com
Engine Dimensions - Mounting Surface View
A232.0 mm (9.13 in.) B8 X 10.3 mm (0.40 in.)
Thru Mounting Holes CMounting Hole "A" D239.5 mm (9.43 in.)
E106.0 mm (4.17 in.) FPTO Mounting
Surface G135.0 mm (5.32 in.) H119.0 mm (4.69 in.)
I16.0 mm (0.63 in.)
A
B
C
D
G
E
F
H
I

Specications
10 62 690 01 Rev. JKohlerEngines.com
Engine Dimensions with Low-Prole Air Cleaner - Flywheel Side
A
B
CD
E
F
G
H
I
J
K
L
M
A484.3 mm (19.07 in.) B364.5 mm (14.35 in.) C106.0 mm (4.17 in.)
Lifting Point D85.7 mm (3.38 in.)
E76.3 mm (3.00 in.) F
Lifting Point
10 X 12 mm
(0.39 X 0.47 in.) Slot
G136.2 mm (5.36 in.) H14.7 mm (0.58 in.)
Spark Plug Lead
IMounting Hole "A" JEngine Mounting
Surface K575.1 mm (22.64 in.) Lifting Point L5.4 mm (0.21 in.) Spark Plug Lead
MOil Fill

Specications
1162 690 01 Rev. J KohlerEngines.com
Engine Dimensions with Low-Prole Air Cleaner - PTO Side
A427.8 mm (18.84 in.) B107.9 mm (4.25 in.) C85.5 mm (3.37 in.)
Lifting Point D
Lifting Point
10 X 12 mm
(0.39 X 0.47 in.) Slot
EOil Level Dipstick FM8 X 1.25 mm Studs G45° H35°
I30° J60.0 mm (2.37 in.)
Exhaust Port #1 K481.2 mm (16.47 in.) Lifting Point L340.8 mm (13.42 in.)
M181.9 mm (7.16 in.)
Starter Stud NMounting Hole "A" O68.6 mm (2.70 in.) Starter Stud P106.0 mm (4.17 in.)
Q177.8 mm (7.01 in.)
Pilot R
M8 X 1.25 mm-6H in.
25 mm (0.98 in.)
Deep on a Ø 254 mm
(10.0 in.) B.C.
S
4 X 7/16-14 UNC-2B in.
21 mm (0.83 in.) Deep
on a Ø 142.88 mm
(5.625 in.) B.C.
T
4 X 3/8-16 UNC-2B in.
17 mm (0.67 in.)
Deep on a Ø 196.88
mm (7.750 in.) B.C.
U142.9 mm (5.63 in.) V254.0 mm (10 in.) W196.9 mm (7.75 in.) X2 X 35.0 mm (1.38 in.)
Gasket
Y60.0 mm (2.36 in. )
Exhaust Port #2
A
D
C
B
E
F
G
G
J
Y
X
K
L
M
N
OPG
G
Q
R
S
T
U
V
W
GG
II
H H

Specications
12 62 690 01 Rev. JKohlerEngines.com
Engine Dimensions with Low-Prole Air Cleaner - Starter Side
A50.0 mm (1.97 in.)
Oil Filter Removal BCylinder #1 Shroud C570.8 mm (22.47 in.) D
45.0 mm (1.77 in.)
Cylinder #1 Shroud
Removal
E181.9 mm (7.16 in.)
Starter Stud FGrass Screen G
422.7 mm (16.64 in.)
Cylinder #1 Shroud
Removal
H401.7 mm (15.82 in.)
IMounting Hole "A" J58.8 mm (2.31 in.)
Spark Plug K91.5 mm (3.6 in.) L239.5 mm (9.43 in.)
MOil Drain Plug
1/2 NPT Inch N13.9 mm (0.55 in.) OEngine Mounting Surface PPTO Mounting Surface
Q155.6 mm (6.13 in.) R10.8 mm (0.42 in.) S28.98 mm (1.06 in.) T
3/8-16 UNC-2B in.
29.0 mm (1.14 in.)
Deep
U23.8 mm (0.94 in.) VStarter Stud
A
B
C
E
F
I
G
H
L
K
J
M
NO
P
Q
S
R
T
U
V
D

Specications
1362 690 01 Rev. J KohlerEngines.com
Engine Dimensions with Low-Prole Air Cleaner - Opposite Starter Side
A254.3 mm (10.01 in.) B
63.0 mm (2.48 in.)
Air Cleaner
Cover Removal
C184.8 mm (7.28 in.) D26.7 mm (1.05 in.)
ELifting Point F
45.0 mm (1.77 in.)
Cylinder #2
Shroud Removal
GCylinder #2 Shroud HAccess to
Oil Cooler
IMounting Hole "A" J81.8 mm (3.22 in.)
Spark Plug K91.5 mm (3.60 in.) L
422.7 mm (16.64 in.)
Cylinder #2
Shroud Removal
MOil Drain Plug
1/2 NPT Inch N13.8 mm (0.55 in.) OEngine Mounting Surface PPTO Mounting Surface
Q600.1 mm (23.63 in.) ROil Pressure
Switch
A
C
B
Q
L
M K
ONJ
E
R
P
H
G
F
E
D
I

Specications
14 62 690 01 Rev. JKohlerEngines.com
ENGINE IDENTIFICATION NUMBERS
Kohler engine identication numbers (model, specication and serial) should be referenced for efcient repair,
ordering correct parts, and engine replacement.
GENERAL SPECIFICATIONS3,6 CH940 CH960 CH980 CH1000
Bore 90 mm (3.54 in.)
Stroke 78.5 mm (3.1 in.)
Displacement 999 cc (61 cu. in.)
Oil Capacity (rell) 1.9 L (2 U.S. qt.)
Maximum Angle of Operation (@ full oil level)425°
TORQUE SPECIFICATIONS3,5 CH940 CH960 CH980 CH1000
Blower Housing and Sheet Metal
M6 Screw
New, Untapped Hole (casting)
Used, Tapped Hole (casting)
New, Extruded Hole (sheet metal)
Used, Extruded Hole (sheet metal)
Mounting Clip (valley bafe)
10.7 N·m (95 in. lb.)
7.3 N·m (65 in. lb.)
2.5 N·m (22 in. lb.)
2.0 N·m (18 in. lb.)
2.5 N·m (22 in. lb.)
Carburetor, Intake Manifold, and Air Cleaner
Intake Manifold Mounting Fastener (torque in 2 increments) rst to 16.9 N·m (150 in. lb.)
nally to 22.6 N·m (200 in. lb.)
Carburetor/Air Cleaner Mounting Nut 11.3 N·m (100 in. lb.)
Carburetor Fuel Bowl Screw 2.5 N·m (22 in. lb.) ± 0.3 N·m (3 in. lb.)
Air Cleaner Mounting Screw (into intake manifold) 11.3 N·m (100 in. lb.)
Closure Plate
Closure Plate Fastener 25.6 N·m (227 in. lb.)
Connecting Rod
Cap Fastener (torque in increments) 11.6 N·m (103 in. lb.)
Control Bracket
Mounting Screw (into intake manifold from air cleaner) 10.2 N·m (90 in. lb.)
3 Values are in Metric units. Values in parentheses are English equivalents.
4 Exceeding maximum angle of operation may cause engine damage from insufcient lubrication.
5Lubricate threads with engine oil prior to assembly.
6 Any and all horsepower (hp) references by Kohler are Certied Power Ratings and per SAE J1940 & J1995 hp
standards. Details on Certied Power Ratings can be found at KohlerEngines.com.
Model.....................CH940
Command Engine
Horizontal Shaft
Numerical Designation
Specication ...............CH940-0001
Serial .....................4323500328
Year Manufactured Code Factory Code
Code Year
43 2013
44 2014
45 2015

Specications
1562 690 01 Rev. J KohlerEngines.com
TORQUE SPECIFICATIONS3,5 CH940 CH960 CH980 CH1000
Control Panel
M6 screw 11.3 N·m (100 in. lb.) into new holes
7.7 N·m (69 in. lb.) into used holes
M5 screws 6.5 N·m (58 in. lb.) into new holes
4.1 N·m (37 in. lb.) into used holes
Crankcase
Breather Cover Fastener 12.4 N·m (110 in. lb.)
Oil Drain Plug 21.4 N·m (16 ft. lb.)
Cylinder Head
Cylinder Head Fastener (torque in 2 increments)
Head Bolt rst to 23.7 N·m (210 in. lb.)
nally to 46.9 N·m (415 in. lb.)
Pipe Plug (3/4 in.) 28.5 N·m (252 in. lb.)
Rocker Arm Screw 15.5 N·m (137 in. lb.)
Debris Screen
Fastener 9.9 N·m (88 in. lb.)
Hex Stud 21.5 N·m (190 in. lb.)
Mounting Screw - Hex Flange Screw 20.3 N·m (180 in. lb.)
Mounting Screw - Button Head Cap Screw 9.9 N·m (88 in. lb.)
Front Drive Shaft Screw (into ywheel) 24.4 N·m (216 in. lb.)
Fan/Flywheel
Fan Fastener Screw - Truss Head 10.4 N·m (92 in. lb.)
Fan Fastener Screw - Hex Head 9.9 N·m (88 in. lb.)
Flywheel Retaining Screw 69.8 N·m (51 ft. lb.)
Governor
Governor Lever Nut 7.1 N·m (63 in. lb.)
Governor Yoke Mounting Screw 2.2 N·m (20 in. lb.)
Ignition
Spark Plug 27 N·m (20 ft. lb.)
Ignition Module Fastener 9.7 N·m (86 in. lb.) into new holes
4.1 N·m (37 in. lb.) into used holes
Rectier-Regulator Fastener 2.5 N·m (22 in. lb.)
Lifter Feed Chamber
Cover/Bafe Screw 7.7 N·m (68 in. lb.)
Mufer
Retaining Nut 24.4 N·m (216 in. lb.)
M6 Screw 9.9 N·m (88 in. lb.)
M8 Screw 24.4 N·m (216 in. lb.)
Oil Cooler
Mounting Screws 2.3 N·m (21 in. lb.)
3 Values are in Metric units. Values in parentheses are English equivalents.
5Lubricate threads with engine oil prior to assembly.

Specications
16 62 690 01 Rev. JKohlerEngines.com
TORQUE SPECIFICATIONS3,5 CH940 CH960 CH980 CH1000
Oil Filter Adapter/Housing
Adapter/Housing Mounting Screw 23.7 N·m (210 in. lb.)
Oil Filter Nipple 17.8 N·m (158 in. lb.)
Oil Pickup Screen
Mounting Screw 9.3 N·m (82 in. lb.) into new holes
7.7 N·m (68 in. lb.) into used holes
Oil Pickup Tube
Mounting Screw 11.3 N·m (100 in. lb.) into new holes
7.7 N·m (68 in. lb.) into used holes
Oil Pump
Mounting Screw 9.9 N·m (88 in. lb.)
Oil SentryTM
Pressure Switch 10.7 N·m (95 in. lb.)
Reservoir (oil)
Mounting Screw 25.6 N·m (227 in. lb.)
Solenoid (starter)
Mounting Hardware 4.0-6.0 N·m (35-53 in. lb.)
Nut, Positive (+) Brush Lead 8.0-11.0 N·m (71-97 in. lb.)
Starter Assembly
Thru Bolt 5.6-9.0 N·m (49-79 in. lb.)
Mounting Screw 16.0 N·m (142 in. lb.)
Brush Holder Mounting Screw 2.5-3.3 N·m (22-29 in. lb.)
Stator
Mounting Screw 9.3 N·m (82 in. lb.)
Throttle/Choke Control Bracket
Fastener 10.2 N·m (90 in. lb.)
Valve Cover
Valve Cover Fastener 13.6 N·m (120 in. lb.)
CLEARANCE SPECIFICATIONS3CH940 CH960 CH980 CH1000
Camshaft
End Play 0.3/1.3 mm (0.011/0.051 in.)
Running Clearance 0.025/0.063 mm (0.0010/0.0025 in.)
Bore I.D.
New
Max. Wear Limit
20.000/20.025 mm (0.7874/0.7884 in.)
20.038 mm (0.7889 in.)
Bearing Surface O.D.
New
Max. Wear Limit
19.962/19.975 mm (0.7859/0.7864 in.)
19.959 mm (0.7858 in.)
3 Values are in Metric units. Values in parentheses are English equivalents.
5Lubricate threads with engine oil prior to assembly.

Specications
1762 690 01 Rev. J KohlerEngines.com
CLEARANCE SPECIFICATIONS3CH940 CH960 CH980 CH1000
Cam Lobe Prole (minimum dimension, measured from base circle
to top of lobe)
Exhaust 35 mm (1.3779 in.)
Intake 34.1 mm
(1.3425 in.)
35 mm (1.3779 in.)
Connecting Rod
Crankpin End I.D. @ 70°F
New
Max. Wear Limit
44.030/44.037 mm (1.7334/1.7337 in.)
0.070 mm (0.0028 in.)
Connecting Rod-to-Crankpin Running Clearance
New
Max. Wear Limit
0.030/0.055 mm (0.0012/0.0022 in.)
0.070 mm (0.0028 in.)
Connecting Rod-to-Crankpin Side Clearance 0.30/0.59 mm (0.0118/0.0232 in.)
Connecting Rod-to-Piston Pin Running Clearance 0.015/0.028 mm (0.0006/0.0011 in.)
Piston Pin End I.D. @ 70°F
New
Max. Wear Limit
19.023/19.015 mm (0.7489/0.7486 in.)
19.036 mm (0.7494 in.)
Crankcase
Governor Cross Shaft Bore I.D.
New
Max. Wear Limit
8.025/8.050 mm (0.3159/0.3169 in.)
8.088 mm (0.3184 in.)
Crankshaft
End Play (free)
Thrust Bearing (Flange)
Non-Thrust Bearing
0.30/1.50 mm (0.011/0.059 in.)
0.20/0.94 mm (0.008/0.037 in.)
Crankshaft Bore (in crankcase)
New, Without Main Bearing
With Main Bearing Installed
Max. Wear Limit
50.00/50.025 mm (1.9685/1.969 in.)
45.040/45.145 mm (1.7732/1.7773 in.)
45.158 mm (1.7778 in.)
Crankshaft to Sleeve Bearing (in crankcase) Running Clearance
New 0.040/0.167 mm (0.0015/0.0065 in.)
Crankshaft Bore (in closure plate)
New, Without Bearing 50.025/50.00 mm (1.9694/1.9685 in.)
Crankshaft to Sleeve Bearing (in closure plate) Running Clearance
New 0.040/0.167 mm (0.0015/0.0065 in.)
Closure Plate End Main Bearing Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
44.978/45.00 mm (1.770/1.771 in.)
44.90 mm (1.767 in.)
0.022 mm (0.0009 in.)
0.025 mm (0.0010 in.)
Connecting Rod Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
Width
43.982/44.000 mm (1.731/1.732 in.)
43.97 mm (1.731 in.)
0.018 mm (0.0007 in.)
0.025 mm (0.0010 in.)
53.00/53.09 mm (2.0866/2.0901 in.)
Crankshaft T.I.R.
PTO End, Crank in Engine
Entire Crank, in V-Blocks
0.279 mm (0.0110 in.)
0.10 mm (0.0039 in.)
3 Values are in Metric units. Values in parentheses are English equivalents.

Specications
18 62 690 01 Rev. JKohlerEngines.com
CLEARANCE SPECIFICATIONS3CH940 CH960 CH980 CH1000
Flywheel End Main Bearing Journal
O.D. - New
O.D. - Max. Wear Limit
Max. Taper
Max. Out-of-Round
44.978/45.00 mm (1.770/1.771 in.)
44.90 mm (1.767 in.)
0.022 mm (0.0009 in.)
0.025 mm (0.0010 in.)
Cylinder Bore
Cylinder Bore I.D.
New
Max. Wear Limit
Max. Taper
Max. Out-of-Round
90.000/90.025 mm (3.543/3.544 in.)
90.075 mm (3.546 in.)
0.013 mm (0.00051 in.)
0.013 mm (0.00051 in.)
Cylinder Head
Max. Out-of-Flatness 0.076 mm (0.003 in.)
Governor
Governor Cross Shaft-to-Crankcase Running Clearance 0.025/0.087 mm (0.0009/0.0034 in.)
Governor Cross Shaft O.D.
New
Max. Wear Limit
7.963/8.000 mm (0.3135/0.3149 in.)
7.936 mm (0.3124 in.)
Governor Gear Shaft-to-Governor Gear Running Clearance 0.070/0.160 mm (0.0027/0.0063 in.)
Governor Gear Shaft O.D.
New
Max. Wear Limit
5.990/6.000 mm (0.2358/0.2362 in.)
5.977 mm (0.2353 in.)
Ignition
Spark Plug Gap 0.76 mm (0.030 in.)
Ignition Module Air Gap (CDI/MDI Ignition Module) 0.28/0.33 mm (0.011/0.013 in.)
Crankshaft Bearing (ywheel/PTO)
New (installed)
Max. Wear Limit
45.040/45.145 mm (1.773/1.777 in.)
45.158 mm
Piston, Piston Rings, and Piston Pin
Piston Style A
Piston-to-Piston Pin Running Clearance 0.006/0.018 mm (0.0002/0.0007 in.)
Piston Pin Bore I.D.
New
Max. Wear Limit
19.006/19.013 mm (0.7482/0.7485 in.)
19.025 mm (0.7490 in.)
Piston Pin O.D.
New
Max. Wear Limit
18.995/19.000 mm (0.7478/0.7480 in.)
18.994 mm (0.7478 in.)
Top Compression Ring-to-Groove Side Clearance 0.04/0.08 mm (0.0015/0.0031 in.)
Middle Compression Ring-to-Groove Side Clearance 0.04/0.08 mm (0.0015/0.0031 in.)
Oil Control Ring-to-Groove Side Clearance 0.03/0.19 mm (0.0011/0.0074 in.)
Top and Middle Compression Ring End Gap
New
Max. Wear Limit
0.30/0.55 mm (0.011/0.021 in.)
0.94 mm (0.037 in.)
Piston Thrust Face O.D.7
New Bore
Used Bore (max.)
89.953/89.967 mm (3.5414/3.5420 in.)
89.925 mm (3.540 in.)
Piston Thrust Face-to-Cylinder Bore7Running Clearance
New 0.033/0.72 mm (0.0013/0.0028 in.)
3 Values are in Metric units. Values in parentheses are English equivalents.
7Measure 11 mm (0.4331 in.) above bottom of piston skirt at right angles to piston pin.

Specications
1962 690 01 Rev. J KohlerEngines.com
CLEARANCE SPECIFICATIONS3CH940 CH960 CH980 CH1000
Piston, Piston Rings, and Piston Pin (continued)
Piston Style B
Piston-to-Piston Pin Running Clearance 0.006/0.017 mm (0.0002/0.0007 in.)
Piston Pin Bore I.D.
New
Max. Wear Limit
20.006/20.012 mm (0.7876/0.7879 in.)
20.025 mm (0.7884 in.)
Piston Pin O.D.
New
Max. Wear Limit
19.995/20.000 mm (0.7872/0.7874 in.)
19.994 mm (0.7872 in.)
Top Compression Ring-to-Groove Side Clearance 0.030/0.070 mm (0.001/0.0026 in.)
Middle Compression Ring-to-Groove Side Clearance 0.030/0.070 mm (0.001/0.0026 in.)
Oil Control Ring-to-Groove Side Clearance 0.060/0.190 mm (0.0022/0.0073 in.)
Top Compression Ring End Gap
New
Max. Wear Limit
0.125/0.304 mm (0.0049/0.0120 in.)
0.515 mm (0.0203 in.)
Middle Compression Ring End Gap
New
Max. Wear Limit
0.900/1.179 mm (0.0354/0.0464 in.)
1.432 mm (0.0564 in.)
Piston Thrust Face O.D.7
New Bore
Used Bore (max.)
89.972 mm (3.5422 in.)
89.827 mm (3.5365 in.)
Piston Thrust Face-to-Cylinder Bore7Running Clearance
New 0.021/0.060 mm (0.0008/0.00236 in.)
Valves and Valve Lifters
Hydraulic Valve Lifter to Crankcase Running Clearance 0.012/0.050 mm (0.0004/0.0019 in.)
Intake Valve Stem-to-Valve Guide Running Clearance 0.038/0.076 mm (0.0015/0.0030 in.)
Exhaust Valve Stem-to-Valve Guide Running Clearance 0.050/0.088 mm (0.0020/0.0035 in.)
Intake Valve Guide I.D.
New
Max. Wear Limit
7.038/7.058 mm (0.2771/0.2779 in.)
7.135 mm (0.2809 in.)
Exhaust Valve Guide I.D.
New
Max. Wear Limit
7.038/7.058 mm (0.2771/0.2779 in.)
7.159 mm (0.2819 in.)
Valve Guide Reamer Size
Standard
0.25 mm O.S.
7.048 mm (0.2775 in.)
7.298 mm (0.2873 in.)
Nominal Valve Face Angle 45°
3 Values are in Metric units. Values in parentheses are English equivalents.
7Measure 11 mm (0.4331 in.) above bottom of piston skirt at right angles to piston pin.

Specications
20 62 690 01 Rev. JKohlerEngines.com
GENERAL TORQUE VALUES
Metric Fastener Torque Recommendations for Standard Applications
Property Class Noncritical
Fasteners
Into Aluminum
Size 4.8 5.8 8.8 10.9 12.9
Tightening Torque: N·m (in. lb.) ± 10%
M4 1.2 (11) 1.7 (15) 2.9 (26) 4.1 (36) 5.0 (44) 2.0 (18)
M5 2.5 (22) 3.2 (28) 5.8 (51) 8.1 (72) 9.7 (86) 4.0 (35)
M6 4.3 (38) 5.7 (50) 9.9 (88) 14.0 (124) 16.5 (146) 6.8 (60)
M8 10.5 (93) 13.6 (120) 24.4 (216) 33.9 (300) 40.7 (360) 17.0 (150)
Tightening Torque: N·m (ft. lb.) ± 10%
M10 21.7 (16) 27.1 (20) 47.5 (35) 66.4 (49) 81.4 (60) 33.9 (25)
M12 36.6 (27) 47.5 (35) 82.7 (61) 116.6 (86) 139.7 (103) 61.0 (45)
M14 58.3 (43) 76.4 (56) 131.5 (97) 184.4 (136) 219.7 (162) 94.9 (70)
Torque Conversions
N·m = in. lb. x 0.113 in. lb. = N·m x 8.85
N·m = ft. lb. x 1.356 ft. lb. = N·m x 0.737
English Fastener Torque Recommendations for Standard Applications
Bolts, Screws, Nuts and Fasteners Assembled Into Cast Iron or Steel Grade 2 or 5 Fasteners
Into Aluminum
Size Grade 2 Grade 5 Grade 8
Tightening Torque: N·m (in. lb.) ± 20%
8-32 2.3 (20) 2.8 (25) — 2.3 (20)
10-24 3.6 (32) 4.5 (40) — 3.6 (32)
10-32 3.6 (32) 4.5 (40) — —
1/4-20 7.9 (70) 13.0 (115) 18.7 (165) 7.9 (70)
1/4-28 9.6 (85) 15.8 (140) 22.6 (200) —
5/16-18 17.0 (150) 28.3 (250) 39.6 (350) 17.0 (150)
5/16-24 18.7 (165) 30.5 (270) — —
3/8-16 29.4 (260) — — —
3/8-24 33.9 (300) — — —
Tightening Torque: N·m (ft. lb.) ± 20%
5/16-24 — — 40.7 (30) —
3/8-16 — 47.5 (35) 67.8 (50) —
3/8-24 — 54.2 (40) 81.4 (60) —
7/16-14 47.5 (35) 74.6 (55) 108.5 (80) —
7/16-20 61.0 (45) 101.7 (75) 142.5 (105) —
1/2-13 67.8 (50) 108.5 (80) 155.9 (115) —
1/2-20 94.9 (70) 142.4 (105) 223.7 (165) —
9/16-12 101.7 (75) 169.5 (125) 237.3 (175) —
9/16-18 135.6 (100) 223.7 (165) 311.9 (230) —
5/8-11 149.5 (110) 244.1 (180) 352.6 (260) —
5/8-18 189.8 (140) 311.9 (230) 447.5 (330) —
3/4-10 199.3 (147) 332.2 (245) 474.6 (350) —
3/4-16 271.2 (200) 440.7 (325) 637.3 (470) —