woodmizer LT28 G25 Guide

WARNING! Read and understand this
manual before using this machine.
!
LT28 G25 Engine
Safety, Operation, Maintenance
& Parts Manual
003295 Engine, LT28 Gas 25hp rev. D
Safety is our #1 concern!
Form #1353
Used with the
LT28G25 rev. A1.00 - A6.17

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8180 West 10th Street
Indianapolis, Indiana 46214

Table of Contents Section-Page
Table of Contents WM doc 12/7/23 iii
SECTION 1 OPERATION
1.1 Starting The Engine ............................................................................... 1-1
SECTION 2
SECTION 3 MAINTENANCE
2.1 Maintenance ........................................................................................... 2-1
2.2 Safety ..................................................................................................... 2-1
2.3 Cooling System...................................................................................... 2-1
2.4 Air Filter & Pre-Cleaner ........................................................................2-1
2.5 Fuel Filter............................................................................................... 2-1
2.6 Battery.................................................................................................... 2-1
2.7 RPM Adjustments.................................................................................. 2-2
2.8 Miscellaneous Maintenance...................................................................2-2
SECTION 4 REPLACEMENT PARTS
3.1 Fuel Tank 4/2022+ ............................................................................. 3-1
3.2 Fuel Tank A6.12 - 4/2022...................................................................... 3-2
3.3 Fuel Tank Rev. A6.10 - A6.11............................................................... 3-3
3.4 Fuel Tank Rev. A3.00 - A6.09............................................................... 3-4
3.5 Fuel Tank Rev. A3.00 - A6.09............................................................... 3-5
3.6 Fuel Tank Rev. A1.00 - A2.01............................................................... 3-7
3.7 Engine Assembly ................................................................................... 3-9
3.8 Engine Assembly Rev. A1.00 - A4.01.................................................3-11
3.9 Throttle/Clutch Assembly.................................................................... 3-13

About this Manual
Starting The Engine
1
1-1 WM doc 12/7/23 About this Manual
ABOUT THIS MANUAL
This manual is provided as a supplement to the equipment manufacturer’s manuals. This manual provides information spe-
cific 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.
SECTION 1 OPERATION
1.1 Starting The Engine
DANGER! Always be sure the blade is disengaged and clear the path of the blade before starting
the engine. Failure to do so will result in serious injury or death.
Operate your engine/machine only in well ventilated areas.Exhaust gases can cause nausea,
delirium and potentially death unless adequate ventilation is present.
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! 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.
CAUTION! EPA Compliant Gas Tanks Only: Always relieve all fuel pressure inside the tank prior
to filling or connecting fuel fittings. Failure to do so may result in fuel spillage.
EPA Compliant Gas Tanks Only: Disconnect the fuel tank when not in use, or engine flooding or
fuel spillage may result.
1. Close the engine choke by moving the choke lever to the start position.
2. Turn the key switch to the START position and release. Release the key switch to the RUN position after the engine
starts.
3. When the engine starts, slowly open the choke all the way by moving the choke lever to the off position.
ENGINE SHUTOFF
1. Disengage the clutch handle to stop the blade if necessary.
2. Run the engine for 15 seconds with no load, then turn the key switch to the OFF position.
SECTION 1

Maintenance
Maintenance 2
Maintenance WM doc 12/7/23 2-1
SECTION 2 MAINTENANCE
2.1 Maintenance
NOTICE This manual only provides information about additional procedures or procedures to be
performed at different time intervals than found in the manufacturer's manuals. Refer to the man-
ufacturer's manual for complete maintenance instructions.
2.2 Safety
Use caution when performing maintenance or service to the engine.
DANGER! Always be aware of and take proper protective measures against rotating shafts, pul-
leys, fans, etc.
Always stay a safe distance from rotating members and make sure that loose clothing or long
hair does not engage rotating members.
Never touch or perform service functions on a hot engine.
WARNING! Remove the blade before performing any engine service. Failure to do so may result
in serious injury.
Wear proper (eye, breathing, hand, and foot) safety equipment when performing service func-
tions.
Clean sawdust from all guards, vents, control boxes, or any area where sawdust may
gather after every shift. Failure to do so may result in fire, causing death or serious
injury.
2.3 Cooling System
Wash the engine or brush off sawdust and debris every 50 hours of operation.
Clean any screens, cooling fins, and all external surfaces.
Remove any dust, dirt, or oil.
See engine manual for further instructions.
2.4 Air Filter & Pre-Cleaner
Service the pre-cleaner every four hours of operation 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.
Replace the air filter (cleaner) every 200 hours of operation.
Replace the pre-cleaner (element wrapper) every 2000 hours of operation.
See the engine manual for further instructions.
2.5 Fuel Filter
Replace the fuel filter every 100 hours of operation or as required for engine performance.
2.6 Battery
Check the battery electrolyte level every 50 hours of operation. See manufacturer’s manual for instructions.

Maintenance
RPM Adjustments
2
2-2 WM doc 12/7/23 Maintenance
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.
WARNING! Battery posts, terminals and related accessories contain lead and lead compounds,
chemicals known to the State of California to cause cancer and reproductive harm. Wash hands
after handling.
2.7 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 every 200 hours of operation.
Before checking the RPM, make sure belt and brake strap tensions are correct. (See Sawmill Maintenance.)
Check oil, fuel, and coolant levels.
Check that the cable spring, cable guide, cable, and throttle brackets are aligned.
NOTE: It is important that the above components are aligned. Proper alignment allows any slack
in the cable (when engine is idling) to slide down into the cable spring. This maintains free opera-
tion of the cable and prevents the cable from kinking. Make sure the shoulder bolt does not rub
against the crankcase vent tube
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 3600. 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.
2.8 Miscellaneous Maintenance
Clean and inspect the spark arresters every 50 hours of operation. Replace if damaged.
CAUTION! Do not remove the plug wire to check for electrical spark. Damage to the ignition cir-
cuit will result.
Inspect the spark plugs every 100 hours of operation.
Remove any deposits and adjust gap if necessary.
Review the manufacturer's engine manual for maintenance intervals.
See engine manual for further information.
Engine High End RPM Low End RPM
G25 3600 1800

Replacement Parts WM doc 12/7/23 3-1
Replacement Parts
Fuel Tank 4/2022+ 3
SECTION 3 REPLACEMENT PARTS
3.1 Fuel Tank 4/2022+
REF PART # DESCRIPTION COMMENTS QTY.
133037 Assembly, Fuel Tank Tray, LT28/35
1P702 Grommet, 7/8In IDx1 1/4In Groove Dia 1
2P05393 Barb, 1/4 Hose 1/4NPT 1
3P851 Valve, Fuel, In Line Shut Off 1
4P649 Hose Clamp, 7/32in-5/8in 2
5F05010-10 Nut, 3/8-16 Hex Nyl Lock 3
6F05011-3 Washer, 3/8 Flat SAE 6
7F05007-73 Bolt, 3/8-16x3 HH Gr5 3
8F05011-17 Washer, 5/16 SAE Flat 4
9F05011-13 Washer, 5/16 Split Lock 4
10 F05006-15 Bolt, 5/16-18x1/2 HH Gr5 4
11 130288 Cover Weldment, Fuel Tank, Domestic 1
12 130286 Fuel Tank, Domestic 6 Gal 1
133484 Assy, 6.50" Portable Tank Pick Up 1
133483 Cap, 2.25" One Way Kelch 1
133438 Kit, Slant Roll Valve 1
133485 Cap, Ultra 3/6/12 Lens 1
13 103810 Weldment, Fuel Tank Tray 1
14 130283 Extension, Fuel Tray 1
15 F05006-86 Bolt, 5/16-18x3/4 Carriage 2
16 F05010-221 Nut, 5/16-18 Flanged Hex Nylock 2

Replacement Parts
Fuel Tank A6.12 - 4/2022
3
3-2 WM doc 12/7/23 Replacement Parts
3.2 Fuel Tank A6.12 - 4/2022
REF PART # DESCRIPTION COMMENTS QTY.
103816 TRAY ASSEMBLY, LT28/35 FUEL TANK 1
1103810 Weldment, Fuel Tank Tray 1
2103867 Cover, Fuel Tank 1
3103878 Tank, 5 Gallon Low Pro EPA Fuel 1
4061250 Grommet, Shut Off 1
5061251 Gas Cap, LT15 1
6061252 Valve, Slosh 1
7061253 Grommet, Slosh Valve 1
8074943 Fitting, Fuel Pick-Up With Shut-Off 1
9F05006-15 Bolt, 5/16-18 x 1/2” Hex Head Grade 5 4
10 F05007-73 Bolt, 3/8-16 x 3” Hex Head Grade 5 3
11 F05010-10 Nut, 3/8-16 Hex Nyloc 3
12 F05011-3 Washer, 3/8” Flat SAE 6
13 F05011-13 Washer, 5/16” Split Lock 4
14 F05011-17 Washer, 5/16” SAE Flat 4
R02423-1 Hose, Fuel 3/16" EPA 15G CARB 6 Ft
R02423-2 Hose, Fuel 1/4" EPA 15G CARB 6 Ft
1
2
5
3
7
4
6
8
9
13
14
10
11
12
280061C

Replacement Parts WM doc 12/7/23 3-3
Replacement Parts
Fuel Tank Rev. A6.10 - A6.11 3
3.3 Fuel Tank Rev. A6.10 - A6.11
REF PART # DESCRIPTION COMMENTS QTY.
076479 TRAY ASSEMBLY, LT28 GAS CAN 1
074643 Tank Assembly, 6 Gallon Gas Service 1
1076478 Tank, Gasoline Available in assemblies only. 1
2015583 Fitting, 1/4” NPT Male Quick Disconnect 1
3015582 Fitting, Female Quick Disconnect Barb 1
4P649 Clamp, 7/32” - 1/2” Hose 2
5076480 Tray Weldment, LT28 Fuel 1
6F05005-34 Bolt, 1/4-20 X 1” Carriage 2
7F05010-21 Nut, 1/4-20 Swaged 2
8P11668 Strap, 20 Rubber W/Hooks 2
9F05007-29 Bolt, 3/8-16 x 2 3/4” Hex Head 2
10 F05011-3 Washer, 3/8” SAE Flat 2
11 F05010-10 Nut, 3/8-16 Hex Nylon Lock 2
R02423-2 Hose, Fuel 1/4" EPA 15G CARB 6.1 Ft
1
3
2
4
5
6
7
8
910 11
280060

Replacement Parts
Fuel Tank Rev. A3.00 - A6.09
3
3-4 WM doc 12/7/23 Replacement Parts
3.4 Fuel Tank Rev. A3.00 - A6.09
REF PART # DESCRIPTION COMMENTS QTY.
076479 TRAY ASSEMBLY, LT28 GAS CAN 1
074643 Tank Assembly, 6 Gallon Gas Service 5 gallon gas can assemblies are
available only for customers
with sawmills and edgers manu-
factured prior to 2010 (See Sec-
tion 4.4).
1
1076478 Tank, Gasoline Available in assemblies only. 1
2015583 Fitting, 1/4” NPT Male Quick Disconnect 1
3015582 Fitting, Female Quick Disconnect Barb 1
4P649 Clamp, 7/32” - 1/2” Hose 2
5076480 Tray Weldment, LT28 Fuel 1
6F05005-34 Bolt, 1/4-20 X 1” Carriage 2
7F05010-21 Nut, 1/4-20 Swaged 2
8P11668 Strap, 20 Rubber W/Hooks 2
9F05007-29 Bolt, 3/8-16 x 2 3/4” Hex Head 2
10 F05011-3 Washer, 3/8” SAE Flat 2
11 F05010-10 Nut, 3/8-16 Hex Nylon Lock 2
R02423-2 Hose, Fuel 1/4" EPA 15G CARB 6.1 Ft
1
3
2
4
5
6
7
8
910 11
280060-2