woodmizer G18 LT20 Series Guide

G18 Engine
Safety, Operation, Maintenance
& Parts Manual
LT20 Series rev. D6.02
Safety is our #1 concern! Read and understand
all safety information and instructions before oper-
ating, setting up or maintaining this machine.
Form #617
!
This is the original language
for the manual.

2 G18doc040312 Table of Contents
Table of Contents Section-Page
SECTION 1 OPERATION 1-1
1.1 Starting The Engine................................................................................1-1
SECTION 2 MAINTENANCE 2-1
2.1 Safety......................................................................................................2-1
2.2 Cooling System ......................................................................................2-2
2.3 Air Filter & Pre-Cleaner.........................................................................2-2
2.4 Engine Oil & Filter.................................................................................2-2
2.5 Fuel Filter ...............................................................................................2-3
2.6 Battery ....................................................................................................2-3
2.7 Alternator Belt........................................................................................2-4
2.8 RPM Adjustments ..................................................................................2-5
2.9 Miscellaneous Maintenance ...................................................................2-6
SECTION 3 REPLACEMENT PARTS 3-1
3.1 How To Use The Parts List....................................................................3-1
3.2 Sample Assembly...................................................................................3-1
3.3 Fuel Tank Assembly...............................................................................3-2
3.4 Engine Mount Assembly........................................................................3-4
3.5 Engine Assembly....................................................................................3-5
3.6 Muffler Assembly...................................................................................3-6
3.7 Drive Assembly......................................................................................3-7
3.8 Throttle Cable Assembly........................................................................3-8
3.9 Alternator Assembly...............................................................................3-9

About This Manual G18doc062110 3
ABOUT THIS MANUAL
This manual is provided as a supplement to the equipment manufacturer’s manuals. This
manual provides information specific to the use of this equipment on the Wood-Mizer®
sawmill. Refer to the sawmill operator’s manual and manufacturer's manual before
attempting to operate this equipment.
IMPORTANT! Read the sawmill operator’s manual and
engine manufacturer’s manual for instructions and safety
precautions before operating this equipment.
The information and instructions given in this manual do not amend or extend the limited
warranties for the equipment given at the time of purchase.
ENGINE COMPONENTS
!
Air Filter Muffler
Serial Number/
Engine Type
3H0509-4
Alternator
S
t
a
rt
e
r

Operation
Starting The Engine
1
1-1 G18doc062110 Operation
SECTION 1 OPERATION
1.1 Starting The Engine
Engine Control Lights
See Figure 1-1. The following indicator lights are located on the sawmill control panel.
Alternator Charge Indicator: Lights up if the alternator is not charging the battery.
Engine Temperature Indicator: Lights up if the engine is overheating.
Oil Indicator: Lights up if the oil pressure is too low.
FIG. 1-1
SW-08 Setworks
Real Size (mm)
Error calibration
Start autoprogram
AUTO
CAL.
SIZE
A
,B,C
Position Size (mm)
NEXT CUT
ABC
Delete PROG.
Exit PROG.
PATTERN DOWN
Save PROG.
SAVE
PATTERN UP
BUMP UP
PROGRAM

Operation
Starting The Engine
Operation G18doc062110 1-2
1
Engine Start
DANGER! Always be sure the blade is disengaged and all
persons are out of the path of the blade before starting the
engine. Failure to do so will result in serious injury.
DANGER! Operate your engine/machine only in well venti-
lated areas. The exhaust gases of your engine can cause
nausea, delirium and potentially death unless adequate
ventilation is present.
DANGER! Never operate an engine with a fuel or oil leak.
The leaking fuel or oil could potentially come in contact with
hot surfaces and ignite into flames.
WARNING! Be sure the power feed switch is in the neutral
position before turning the key switch to the on (#1) posi-
tion. This prevents accidental carriage movement, which
may cause serious injury or death.
WARNING! Do not operate engine without proper and
operational spark arrester/muffler. Sparks emitted from the
engine exhaust could ignite surrounding materials, causing
serious injury or death.
Turn the key switch to the start (#2) position and release.
If the engine needs choking to start, pull the choke cable out until the engine starts. Push
the choke wire in after the engine starts.
For more information, see the engine manufacturer’s operation manual.
If the fuel tank was recently filled or replaced, squeeze the primer bulb once or twice
before trying to start the engine. NOTE: If pumping problems are experienced, make sure
the out-flow end of the hose line is connected to the fuel filter. If pumping problems are
still experienced, hold the primer bulb in a vertical position while squeezing. This allows
the fuel check valve to operate properly.
NOTE: When the clutch handle is engaged, an accelerator pump is activated which sup-
plies fuel to the engine carburetor. To avoid flooding the carburetor and possibly fouling
the spark plugs, do not engage the clutch lever repeatedly without the engine running.

Operation
Starting The Engine
1
1-3 G18doc062110 Operation
Engine Shutoff
Turn the key switch to the off (#0) position.

Maintenance
Safety
Maintenance G18doc062110 2-1
2
SECTION 2 MAINTENANCE
Refer to the manufacturer’s manual for maintenance intervals and procedures unless oth-
erwise instructed in this manual. Follow the manufacturer’s recommendations for dusty
conditions.
IMPORTANT! This manual only provides information about
additional procedures or procedures to be performed at dif-
ferent time intervals than found in the manufacturer's manu-
als. Refer to the manufacturer's manual for complete
maintenance instructions.
2.1 Safety
Use caution when performing maintenance or service to the engine.
DANGER! Always be aware of and take proper protective
measures against rotating shafts, pulleys, fans, etc. Always
stay a safe distance from rotating members and make sure
that loose clothing or long hair does not engage rotating
members resulting in possible injury.
DANGER! Engine components can become very hot during
operation. Avoid contact with any part of a hot engine. The
exhaust components of your engine are especially hot dur-
ing and following operation. Contact with hot engine com-
ponents can cause serious burns. Therefore, never touch
or perform service functions on a hot engine. Allow the
engine to cool sufficiently before beginning any service
function.
WARNING! Remove the blade before performing any
engine service. Failure to do so may result in serious injury.
WARNING! Always wear proper and necessary safety
equipment when performing service functions. Proper
safety equipment includes eye protection, breathing protec-
tion, hand protection and foot protection.
This symbol identifies the interval (hours of operation) at which each maintenance pro-
cedure should be performed. "AR" signifies maintenance procedures which should be
performed as required.
!
0

Maintenance
Cooling System
2
2-2 G18doc062110 Maintenance
2.2 Cooling System
Wash the engine or brush off sawdust and debris every 50 hours of operation. Clean the
grass screen, cooling fins, and external surfaces. Remove any dust, dirt or oil. See
engine manual for further instructions.
2.3 Air Filter & Pre-Cleaner
WARNING! Always wear proper and necessary safety
equipment when performing service functions. Proper
safety equipment includes eye protection, breathing protec-
tion, hand protection and foot protection.
Service the pre-cleaner every four hours of operation. Service by gently shaking excess
sawdust and debris from the foam piece.
Clean the air filter (air cleaner element) and pre-cleaner (element wrapper) every eight
hours of operation. See the engine manual for further instructions.
Replace the air filter (cleaner) every 200 hours of operation.
Replace the pre-cleaner (element wrapper) every 2000 hours of operation.
2.4 Engine Oil & Filter
Check the oil level every 8 hours of operation. Add oil as necessary. See the engine man-
ual for oil viscosity and grade recommendations.
IMPORTANT! During initial break-in, change the oil and the
oil filter after the first 5 hours and every 50 hours thereafter.
Continue to check oil level every 8 hours of operation and
refill as necessary.
NOTE: Engine at factory is filled with 10W/40 Shell Helix HX7, semi-synthetic oil.
50
4
8
200
2000
8
50

Maintenance
Fuel Filter
Maintenance G18doc062110 2-3
2
2.5 Fuel Filter
IMPORTANT! For best results use only clean, fresh,
unleaded gasoline with a pump sticker octane rating of 87
or higher. In countries using the Research method, it sholud
be 90 octane minimum.
Replace the fuel filter every 100 hours of operation.
2.6 Battery
Check the battery electrolyte level every 50 hours of operation. See manufacturer’s man-
ual for instructions.
DANGER! Batteries expel explosive gases. Keep sparks,
flames, burning cigarettes, or other ignition sources away at
all times. Always wear safety goggles and a face shield
when working near batteries. Failure to do so will cause
serious injury.1
WARNING! Battery posts, terminals and related accesso-
ries contain lead and lead compounds, chemicals known to
the State of California to cause cancer and reproductive
harm. Wash hands after handling.
1. Battery Council International, copyright 1987
!
100
50

Maintenance
Alternator Belt
2
2-4 G18doc062110 Maintenance
2.7 Alternator Belt
Adjust the alternator belt as needed. Check the alternator belt for tension and wear when
battery is not charging properly or when the alternator belt is squealing. To tighten the
belt, loosen the adjustment bolt and lock washer. Pivot the alternator away from the motor
until the belt has 7/16" (11 mm) deflection with a 5 lb. deflection force. Retighten the
adjustment bolt.
See Figure 2-1.
FIG. 2-1
AR
20_095
Loosen bolt to
pivot alternator
clockwise and
tighten belt

Maintenance
RPM Adjustments
Maintenance G18doc062110 2-5
2
2.8 RPM Adjustments
WARNING! Remove the blade before performing any
engine service. Failure to do so may result in serious injury.
Check the RPM with a tachometer after the first 20 hours of operation and every 200
hours thereafter. High-end RPM should be 3750 RPM and low-end RPM should be 1800
RPM (±100).
Before checking the RPM, make sure belt and brake strap tensions are correct (See Saw-
mill Maintenance). Also check oil and fuel levels.
Make sure the throttle cable does not affect the engine RPM when the clutch handle is
disengaged. Make sure the cable is not bent or kinked. Check that the cable spring, cable
guide, cable, and throttle brackets are aligned. NOTE: It is important that the above com-
ponents are aligned. Proper alignment allows any slack in the cable (when engine is
idling) to slide down into the cable spring. This maintains free operation of the cable and
prevents the cable from kinking.
1. Start the engine to measure the low-end RPM.
2. Refer to the engine manual to adjust the low-end RPM.
3. Engage the clutch handle to throttle the engine and measure the high-end RPM. The
high-end RPM is factory-set at 3750. Readjust the throttle cable if necessary to increase
or reduce the high-end engine speed.
The throttle cable should be tensioned just enough so that the engine revs as soon as the
clutch/brake handle is engaged. NOTE: A properly adjusted throttle will extend the cable
spring 1/4” to 3/8” (6.4 - 9.5 mm) when running and have a slight amount of slack in the
cable when idling.
200

Maintenance
Miscellaneous Maintenance
2
2-6 G18doc062110 Maintenance
2.9 Miscellaneous Maintenance
Clean and inspect the spark arresters every 50 hours of operation. Replace if damaged.
Inspect the spark plugs every 100 hours of operation. Remove any deposits and adjust
gap if necessary. See engine manual for further information.
CAUTION! Do not remove the plug wire to check for electri-
cal spark. Damage to the ignition circuit will result.
50
100

Replacement Parts
How To Use The Parts List
Replacement Parts G18doc040312 3-1
3
SECTION 3 REPLACEMENT PARTS
3.1 How To Use The Parts List
Use the table of contents or the index to locate the assembly that contains the part
you need.
Go to the appropriate section and locate the part in the illustration.
Use the number pointing to the part to locate the correct part number and descrip-
tion in the table.
Parts shown indented under another part are included with that part.
Parts marked with a diamond () are only available in the assembly listed above the
part.
See the sample table below. Sample Part #A01111 includes part F02222-2 and subas-
sembly A03333. Subassembly A03333 includes part S04444-4 and subassembly
K05555. The diamond () indicates that S04444-4 is not available except in subassembly
A03333. Subassembly K05555 includes parts M06666 and F07777-77. The diamond ()
indicates M06666 is not available except in subassembly K05555.
To Order Parts:
From the continental U.S., call our toll-free Parts hotline at 1-800-448-7881. From
Europe call our European Headquarters and Manufacturing Facility in Kolo, Poland
at [phone] or [phone]. Have your customer number, vehicle identifi-
cation number, and part numbers ready when you call.
From other international locations, contact the Wood-Mizer distributor in your area
for parts.
3.2 Sample Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
SAMPLE ASSEMBLY, COMPLETE (INCLUDES ALL INDENTED PARTS BELOW) A01111 1
1Sample Part F02222-22 1
Sample Subassembly (Includes All Indented Parts Below) A03333 1
2Sample Part (Indicates Part Is Only Available With A03333) S04444-4 1 
Sample Subassembly (Includes All Indented Parts Below) K05555 1
3Sample Part (Indicates Part Is Only Available With K05555) M06666 2 
4Sample Part F07777-77 1

Replacement Parts
Fuel Tank Assembly
3
3-2 G18doc040312 Replacement Parts
3.3 Fuel Tank Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
TANK ASSEMBLY, LT20 SERIES FUEL 092279 1
1Tray, LT20 Series Fuel Tank 091885-1 1
2Bolt, M6x25-8.8 Carriage Head Zinc F81001-20 2
3Nut, M6-8-B Hex Nylon Zinc Lock F81031-2 2
4Washer, 6.5 Zinc Flat Special F81053-11 2
5Strap, 24" Fuel Tank Rubber P11258 2
6Tank, 5-Gallon Red Fuel P12167 1
7Cap, 3 or 5-Gallon Fuel Tank P09683 1
8Pickup, Fuel P12172 2
9Fitting, 1/4" Plastic Male-Female Disconnect P12175 1
10 Fitting, 1/4 Barb Male Disconnect P12176 1
11 Bulb, Fuel Primer 014481 1 
12 Clamp, 1/2" OD Fuel Hose P12374 2
20_067
1
2
3
4
5
6
7
8
9
10
13
13
15
14
15
14
11 12
12
16
16
17

Replacement Parts
Fuel Tank Assembly
Replacement Parts G18doc040312 3-3
3
13 BOLT, M6X20-8.8 HEX HEAD FULL THREAD ZINC F81001-2 3
14 NUT, M6-8-B HEX NYLON ZINC LOCK F81031-2 3
15 WASHER, 6.5 ZINC FLAT SPECIAL F81053-11 3
16 HOSE, 1/4" ID FUEL R01890-1 2 m
17 CLAMP, 1/2" OD FUEL HOSE P12374 1

Replacement Parts
Engine Mount Assembly
3
3-4 G18doc040312 Replacement Parts
3.4 Engine Mount Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
1 MOUNT, G18 ENGINE 092250-1 1
2 BOLT, M10X60-8.8 HEX HEAD ZINC F81003-10 4
3 WASHER, 10.5 ZINC FLAT F81055-1 16
4 NUT, M10-8-B HEX NYLON ZINC LOCK F81033-1 8
5 BOLT, M10X110 8.8 HEX HEAD ZINC F81003-43 4
1
2
3
3
3
3
4
4
5
20_087

Replacement Parts
Engine Assembly
Replacement Parts G18doc040312 3-5
3
3.5 Engine Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
1 ENGINE KIT, KOHLER 18HP BASIC 017622 1 
2Cleaner, Kohler 18HP #47 083 03-S Air 093741 1
3Pre-Cleaner, Kohler 18HP #24 083 02-S Air 093742 1
Plug, RC12YC G13/G15 Kohler #12-132-02-S Spark P12757 2
4Filter, Kohler 18HP #12 050 01-S Oil 093743 1
5Filter, Kohler 18HP #25 050 03-S Fuel 093744 1
1
2
3
4
5
20_093

Replacement Parts
Muffler Assembly
3
3-6 G18doc040312 Replacement Parts
3.6 Muffler Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
1 MUFFLER, 24068 37-S COMMAND 18 092278 1
2 BRACKET, G18 MUFFLER MOUNT 092501-1 1
3 GUARD, GP25/GP18 MUFFLER COMPLETE 091859-1 1
4 BOLT, M6X16 8.8 HEX HEAD FULL THREAD ZINC F81001-15 4
5 WASHER, Z 6.1 SPLIT LOCK ZINC F81053-3 4
6 WASHER, 6.5 ZINC FLAT SPECIAL F81053-11 4
20_088
1
2
3
4
4
5
5
6
6

Replacement Parts
Drive Assembly
Replacement Parts G18doc040312 3-7
3
3.7 Drive Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
1 PULLEY, G18 ENGINE 092253 1
2 KEY, 6.35 X 6.36 X 40 S04124 2
3 SCREW, M8X8-33H FLAT POINT HEX SOCKET SET ZINC F81014-1 1
4 BUSHING, SPACER 092254 1
5 PULLEY, Z95/28.575 092551 1
6 SCREW, M6X8 CONE POINT HEX SOCKET SET ZINC F81013-1 1
7 GUARD, G18 ALTERNATOR DRIVE PULLEY 092603-1 1
8 BOLT, M6X16 8.8 HEX HEAD FULL THREAD ZINC F81001-15 3
9 WASHER, Z 6.1 SPLIT LOCK ZINC F81053-3 3
10 WASHER, 6.5 ZINC FLAT SPECIAL F81053-11 3
V-BELT, BX83 1/2 088110 2
20_089
1
22
3
45
67
8
9
10

Replacement Parts
Throttle Cable Assembly
3
3-8 G18doc040312 Replacement Parts
3.8 Throttle Cable Assembly
REF DESCRIPTION (Indicates Parts Available In Assemblies Only) PART # QTY.
CABLE, G18 THROTTLE COMPLETE 092550 1
1Cable, G18 Throttle 092259 1
2Plate, G18 Throttle Cable Spring Mount Zinc 092531 1
3Bolt, Throttle Cable Clamp Zinc 088120-1 1
4Washer, 6.4 Flat Zinc F81053-1 1
5Nut, M6-8-B Hex Nylon Zinc Lock F81031-2 1
6Spring, 1.3 x 8 x 20 Extension 092549 1
7Bracket, Throttle Cable Spring Mount 091918-1 1
8Spring, 1.6x12x38 Extension 092208 1
9 BRACKET, G18 THROTTLE/TENSIONER HANDLE 092535-1 1
10 SCREW, M6X8 CONE POINT HEX SOCKET SET ZINC F81013-1 2
11 BRACKET, G18 THROTTLE CABLE MOUNT 092532-1 1
12 BOLT, M6X25-5.8 HEX HEAD FULL THREAD ZINC F81001-3 2
13 WASHER, Z 6.1 SPLIT LOCK ZINC F81053-3 2
14 WASHER, 6.5 ZINC FLAT SPECIAL F81053-11 2
15 BRACKET, G25 THROTTLE 091565-1 1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
20_090
1
5