Scag Power Equipment SFC-21-5CV User manual

PART NO. 03536
PRINTED 01/23
PRINTED IN USA
© 2023
Scag Power Equipment
Division of Metalcraft of Mayville, Inc.
Congratulations on owning a Scag mower! This manual contains the operating
instructions and safety information for your Scag mower. Reading this manual
can provide you with assistance in maintenance and adjustment procedures to
keep your mower performing to maximum efciency. The specic models that
this book covers are listed on the inside cover. Before operating your machine,
please read all the information enclosed.
OPERATOR’S
MANUAL
Models: SFC-21-5CV
SFC-21-7CV

WARNING
FAILURE TO FOLLOW SAFE OPERATING PRACTICES MAY RESULT
IN SERIOUS INJURY OR DEATH.
• Read this manual completely as well as other manuals that came with your mower.
• ALWAYS follow all safety instructions on this product and in the manual to avoid personal injury or
death.
• ALWAYS FOLLOW OSHA APPROVED OPERATION.
• This product is capable of amputating hands and feet and throwing objects.
• Keep hands, feet and clothing away from power-driven parts.
• DO NOT operate on steep slopes.
• Always travel across slopes.
• DO NOT mow on wet grass. Wet grass reduces traction and steering control.
• Keep all shields in place, especially the grass discharge chute.
• Before performing any maintenance or service, stop the machine and remove the spark plug wire.
• If a mechanism becomes clogged, stop the engine before cleaning.
• Keep others off the mower (only one person at a time)
REMEMBER - YOUR MOWER IS ONLY AS SAFE AS THE OPERATOR!
HAZARD CONTROL AND ACCIDENT PREVENTION ARE DEPENDENT UPON THE AWARENESS,
CONCERN, PRUDENCE, AND PROPER TRAINING OF THE PERSONNEL INVOLVED IN THE
OPERATION, TRANSPORT, MAINTENANCE, AND STORAGE OF THE EQUIPMENT.
This manual covers the operating instructions and illustrated parts list for:
SFC-21-5CV with a serial number of W2300001 to W2399999
SFC-21-7CV with a serial number of W2400001 to W2499999
Always use the entire serial number listed on the serial number tag when referring to this product.

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Table of Contents
Table of Contents
SECTION 1 - GENERAL INFORMATION...................................................................................1
1.1 INTRODUCTION.........................................................................................................................................1
1.2 DIRECTION REFERENCE.........................................................................................................................1
1.3 SERVICING THE ENGINE AND DRIVE TRAIN COMPONENTS...........................................................1
1.4 ASSEMBLY INSTRUCTIONS ....................................................................................................................2
1.5 SYMBOLS ...................................................................................................................................................3
SECTION 2 - SAFETY INFORMATION ......................................................................................4
2.1 INTRODUCTION.........................................................................................................................................4
2.2 SIGNAL WORDS ........................................................................................................................................4
2.3 BEFORE OPERATION CONSIDERATIONS ............................................................................................4
2.4 TESTING THE BLADE STOP SYSTEM ...................................................................................................5
2.5 OPERATION CONSIDERATIONS.............................................................................................................6
2.6 MAINTENANCE CONSIDERATIONS & STORAGE................................................................................7
2.7 USING A SPARK ARRESTOR...................................................................................................................8
2.8 SPARK IGNITION SYSTEM.......................................................................................................................8
2.9 SAFETY AND INSTRUCTIONAL DECALS..............................................................................................9
SECTION 3 - SPECIFICATIONS ..............................................................................................10
3.1 ENGINE .....................................................................................................................................................10
3.2 CONTROLS...............................................................................................................................................10
3.3 MOWER .....................................................................................................................................................10
3.4 CUTTER DECK.........................................................................................................................................10
3.5 WEIGHTS AND DIMENSIONS ................................................................................................................ 11
3.6 PRODUCTIVITY........................................................................................................................................ 11
SECTION 4 - OPERATING INSTRUCTIONS ...........................................................................12
4.1 CONTROLS AND INSTRUMENT IDENTIFICATION ............................................................................ 12
4.2 TESTING THE BLADE STOP SYSTEM .................................................................................................13
4.3 INITIAL RUN-IN PROCEDURES.............................................................................................................14
4.4 STARTING THE ENGINE.........................................................................................................................14
4.5 GROUND TRAVEL ...................................................................................................................................15
4.6 ENGAGING THE CUTTER BLADES ......................................................................................................15
4.7 SLOPE OPERATION................................................................................................................................16
4.8 PARKING THE MOWER ..........................................................................................................................16
4.9 AFTER OPERATION ................................................................................................................................16
4.10 REMOVING CLOGGED MATERIAL .....................................................................................................17
4.11 MOVING MOWER WITH ENGINE STOPPED......................................................................................17
4.12 RECOMMENDATIONS FOR MOWING ................................................................................................17
4.13 ADJUSTING CUTTING HEIGHT ...........................................................................................................18

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Table of Contents
SECTION 5 - TROUBLESHOOTING CUTTING CONDITIONS ...............................................19
SECTION 6 - ADJUSTMENTS .................................................................................................22
6.1 SELF-PROPEL DRIVE ADJUSTMENTS................................................................................................22
6.2 THROTTLE CONTROL AND CHOKE ADJUSTMENTS ....................................................................... 24
6.3 TRANSMISSION DRIVE BELT................................................................................................................24
6.4 BLADE CONTROL BAR CABLE ADJUSTMENT .................................................................................24
6.5 CUTTER DECK ADJUSTMENTS............................................................................................................25
SECTION 7 - MAINTENANCE..................................................................................................26
7.1 MAINTENANCE CHART - RECOMMENDED SERVICE INTERVALS ................................................26
7.2 ENGINE OIL ..............................................................................................................................................27
7.3 ENGINE FUEL SYSTEM ..........................................................................................................................27
7.4 ENGINE AIR CLEANER...........................................................................................................................29
7.5 DRIVE BELT..............................................................................................................................................29
7.6 CUTTER BLADE.......................................................................................................................................30
7.7 WHEELS....................................................................................................................................................31
7.8 BODY AND DECK ....................................................................................................................................31
SECTION 8 - ILLUSTRATED PARTS LIST..............................................................................32
8.1 SCAG APPROVED ATTACHMENTS AND ACCESSORIES ................................................................32
CUTTER DECK...............................................................................................................................................34
SHEET METAL COMPONENTS....................................................................................................................36
BAG ASSEMBLY ............................................................................................................................................38
HANDLE BAR COMPONENTS .....................................................................................................................40
REAR DRIVE SYSTEM COMPONENTS ......................................................................................................42
FUEL SYSTEM (EXCLUDES CA MODELS) ................................................................................................44
REPLACEMENT DECALS AND INFORMATION PLATES ........................................................................46
SECTION 9 - LIMITED WARRANTY - SFC Commercial 21 ........................INSIDE BACK COVER

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Section 1
GENERAL INFORMATION
USE ONLY SCAG APPROVED ATTACHMENTS
AND ACCESSORIES.
Attachments and accessories manufactured by companies
other than Scag Power Equipment are not approved for
use on this machine. See Section 8-1. Be aware that using
attachments with the mower may affect stability. Be sure to
follow the directions found in the operator's manual. See
Section 8, Paragraph 8-1.
WARNING
For pictorial clarity, some illustrations and gures
in this manual may show shields, guards or plates
open or removed. Under no circumstances should
your mower be operated without these devices
in place.
All information is based upon product information available
at the time of approval for printing. Scag Power Equipment
reserves the right to make changes at any time without
notice and without incurring any obligation.
1.2 DIRECTION REFERENCE
The “Right” and “Left”, “Front” and “Rear” of the machine
are referenced from the operator’s right and left when in
the normal operating position and facing the forward travel
direction.
1.3 SERVICING THE ENGINE AND DRIVE
TRAIN COMPONENTS
The detail servicing and repair of the engine, transmissions
and gearboxes are not covered in this manual; only
routine maintenance and general service instructions
are provided. For service of these components during
the limited warranty period, it is important to contact your
Scag dealer or find a local authorized servicing agent of
the component manufacturer. Any unauthorized work done
on these components during the warranty period may void
your warranty.
1.1 INTRODUCTION
Your mower was built to the highest standards in the
industry. However, the prolonged life and maximum
efficiency of your mower depends on you following the
operating, maintenance and adjustment instructions in
this manual.
If additional information or service is needed, contact your
Scag Power Equipment Dealer.
We encourage you to contact your dealer for repairs. All
Scag dealers are informed of the latest methods to service
this equipment and provide prompt and efficient service in
the field or at their service shop. They carry a full line of
Scag service parts.
THE REPLACEMENT OF ANY PART ON THIS
PRODUCT BY OTHER THAN THE MANUFACTURER'S
AUTHORIZED REPLACEMENT PART MAY
ADVERSELY AFFECT THE PERFORMANCE,
DURABILITY OR SAFETY OF THIS PRODUCT.
USE OF OTHER THAN ORIGINAL SCAG
REPLACEMENT PARTS WILL VOID THE WARRANTY.
When ordering parts, always give the model and serial
number of your mower. The serial number plate is located
on the right side on the frame. See Figure 1-1.
LOT
ABCD
1234
Division of Metalcraft of Mayville
Assembled in West Bend, WI
www.scag.com/patents
Meets CPSC
blade safety
requirements
Figure 1-1. Mower Serial Number Plate Location

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Section 1
1.4 ASSEMBLY INSTRUCTIONS
1. In an open area, remove the grass bag, hardware bag and
mower from the packaging.
2. With help from an assistant, loosen the two (2) 3/8-16 elastic
flange nuts identified and raise the handle bar assembly. See
Figure 1-2.
2
1
1
Figure 1-2. Lift the Handle Bar Assembly
3. While holding the handle bar assembly in place, Secure using
four (4) 3/8-16 x 3/4" carriage bolts and four (4) 3/8-16 elastic
flange nuts provided as shown Tighten mounting hardware and
pivot bolts See Figure 1-3.
2
4
1
3
Figure 1-3. Secure the Handle Bar Assembly
4. The engine installed on this mower is shipped "dry" from
the factory. Add the recommended amount of oil to the engine
per the engine operator's manual supplied with this mower.
5. Install the fabric grass collection bag over the bag frame
weldment. See Figure 1-4.
Figure 1-4. Install the Fabric Grass Collection Bag
6. Secure the fabric grass collection bag to the frame weldment
using the eight (8) hooks located on the each side. See Figure
1-5.
1
2
3
4
5
8
7
6
Figure 1-5. Install the Grass Collection Bag
7. Install the grass collection bag onto the back of the mower.
8. Assembly is now complete on the mower.

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Section 1
1.5 SYMBOLS
SYMBOL DESCRIPTION SYMBOL DESCRIPTION
Choke Transmission
Parking Brake
48071S
Spinning Blade
On/Start Spring Tension on Idler
Off/Stop Oil
Falling Hazard Thrown Object Hazard
Fast Slow
Continuously Variable - Linear Cutting Element - Basic Symbol
481039S
Pinch Point Cutting Element - Engage
Hour meter/Elapsed Operating Hours Cutting Element - Disengage
Keep Bystanders Away Read Operator's Manual

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Section 2
2.1 INTRODUCTION
Your mower is only as safe as the operator. Carelessness or operator
error may result in serious bodily injury or death. Hazard control and
accident prevention are dependent upon the awareness, concern,
prudence, and proper training of the personnel involved in the operation,
transport, maintenance and storage of the equipment. Make sure
every operator is properly trained and thoroughly familiar with all of the
controls before operating the mower. The owner/user can prevent and
is responsible for accidents or injuries occurring to themselves, other
people or property.
This product is capable of amputating hands and feet and throwing
objects. Always follow all safety instructions on this product and in the
manual to avoid personal injury or death.
READ THIS OPERATOR’S MANUAL BEFORE
ATTEMPTING TO START YOUR MOWER. MAKE
SURE THAT EVERYONE KNOWS WHERE THE
MANUAL IS LOCATED AND KEEP A RECORD OF
EACH EMPLOYEE THAT HAS READ THE MANUAL.
A replacement manual is available from your authorized Scag Service
Dealer or by contacting Scag Power Equipment, Service Department
at P.O. Box 152, Mayville, WI 53050 or contact us via the Internet at
www.scag.com. The manual for this machine can be downloaded by
using the model and serial number or use the contact form to make your
request. Please indicate the complete model and serial number of your
Scag product when requesting replacement manuals.
2.2 SIGNAL WORDS
This symbol means “Attention! Become Alert! Your Safety
is Involved!" The symbol is used with the following signal words
to attract your attention to safety messages found on the decals on the
machine and throughout this manual. The message that follows the
symbol contains important information about safety. To avoid injury and
possible death, carefully read the message! Be sure to fully understand
the causes of possible injury or death.
SIGNAL WORD:
It is a distinctive word found on the safety decals on the machine and
throughout this manual that alerts the viewer to the existence and
relative degree of the hazard.
DANGER
The signal word “DANGER” denotes that an extremely hazardous
situation exists on or near the machine that could result in high
probability of death or irreparable injury if proper precautions are not
taken.
WARNING
The signal word “WARNING” denotes that a hazard exists on or near
the machine that can result in injury or death if proper precautions are
not taken.
CAUTION
The signal word “CAUTION” is a reminder of safety practices on or near
the machine that could result in personal injury if proper precautions
are not taken.
Your safety and the safety of others depends significantly upon your
knowledge and understanding of all correct operating practices and
procedures of this machine.
2.3 BEFORE OPERATION
CONSIDERATIONS
1. NEVER allow children to operate this mower. Do not allow
adults to operate this machine without proper instructions.
2. Do not mow when children and/or others are present. Keep
children out of the mowing area and in the watchful care of a
responsible adult other than the operator. Be alert and turn
machine off if a child enters the area.
3. DO NOT allow children to ride or play on the machine, it is not
a toy.
4. Clear the area to be mowed of objects that could be picked up
and thrown by the cutter blades.
5. DO NOT carry passengers.
6. DO NOT operate the machine under the influence of alcohol or
drugs.
SAFETY INFORMATION

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Section 2
7. If the operator(s) or mechanic(s) cannot read English, it is the
owner's responsibility to explain this material to them. A Spanish
decal kit is available for this model. See your local Scag Dealer.
8. DO NOT wear loose fitting clothing. Loose clothing, jewelry
or long hair could get tangled in moving parts. Do not operate
the machine wearing shorts; always wear adequate protective
clothing including long pants and substantial slip-resistant
footwear. Wearing safety glasses, safety shoes and a helmet
is advisable and is required by some local ordinances and
insurance regulations.
WARNING
Always wear hearing protection. Operating this
machine over prolonged periods of time can
cause loss of hearing.
9. Keep the machine and attachments in good operating condition.
Keep all shields and safety devices in place. If a shield, safety
device or decal is defective or damaged, repair or replace it
before operating the machine.
10. Fuel is flammable; handle it with care. Fill the fuel tank outdoors.
Never fill it indoors. Use a funnel or spout to prevent spillage.
Clean up any spillage before starting the engine.
11. DO NOT add fuel to a running or hot engine. Allow the engine to
cool for several minutes before adding fuel. Never fuel indoors
or inside enclosed trailers.
12. DO NOT start the engine until any spilled fuel has been cleaned
up or has evaporated.
13. Keep flammable objects (cigarettes, matches, etc.), open flames
and sparks away from the fuel tank and fuel container. Use only
approved containers.
14. See Section 7.3 ENGINE FUEL SYSTEM for fueling procedure.
15. Equipment must comply with the latest requirements per SAE
J137 and/or ANSI/ASAE S279 when driven on public roads.
16. Do not operate without the discharge plug installed or with the
grass catcher installed.
17. Check the blade mounting bolts at frequent intervals for proper
tightness.
2.4 TESTING THE BLADE STOP SYSTEM
The blade stop system should be tested each time before using the
machine. Check that the blade stops within 3 seconds of releasing the
control bar as described below.
-IMPORTANT-
If the blade does not stop within 3 seconds of
releasing the control bar, contact your local
Authorized Scag Power Equipment Dealer
immediately to have the blade stop system
repaired.
TEST USING THE GRASS BAG
1. Remove the rear discharge plug.
2. Install the empty grass bag onto the rear of the machine.
3. Start the engine. Allow the engine to warm up before engaging
the blade.
4. Engage the blade.
-NOTE-
The bag should begin to inflate, indicating that the
blade is rotating.
5. Watch the bag and release the control bar.
6. Immediately start counting out 3 seconds and watch for the bag
to deflate.
-NOTE-
If the bag does not deflate within 3 seconds of
releasing the control bar, the blade stop system
could be deteriorating or out of adjustment. Contact
your local Authorized Scag Power Equipment
Dealer immediately to have the blade stop system
repaired.
7. Shut the engine off and wait for all moving parts to stop.
TEST NOT USING THE GRASS BAG
1. Remove the grass bag.
2. Install the rear discharge plug.
3. Move the machine onto a paved surface such as a driveway,
sidewalk, parking lot or patio next to a section of grass.
4. Position the machine next to a patch of grass and approximately
3" away. See Figure 2-1.
5. Start the engine. Allow the engine to warm up before engaging
the blade.
6. Engage the blade.

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Section 2
-NOTE-
The grass next to the the machine should start to
move from the air flow, indicating that the blade
is rotating.
3”
3”
Figure 2-1. Blade Stop
7. Watch the grass and release the control bar.
8. Immediately start counting out 3 seconds and watch for the
grass to stop moving.
-NOTE-
If the grass does not stop moving within 3 seconds
of releasing the control bar, the blade stop system
could be deteriorating or out of adjustment. Contact
your local Authorized Scag Power Equipment
Dealer immediately to have the blade stop system
repaired.
9. Shut the engine off and wait for all moving parts to stop.
2.5 OPERATION CONSIDERATIONS
1. Know the function of all controls and how to stop quickly.
WARNING
DO NOT operate on steep slopes. ALWAYS
FOLLOW OSHA APPROVED OPERATION.
2. Reduce speed and exercise extreme caution on slopes and in
sharp turns to prevent tipping or loss of control. Be especially
cautious when changing directions on slopes.
3. Do not mow or operate on excessively steep slopes. Poor
footing could cause a slip and fall accident.
4. To prevent tipping or loss of control, start and stop smoothly,
avoid unnecessary turns and travel at reduced speed.
5. Immediately stop the machine if you lose drive control while
operating. Inspect the machine and correct the problem before
continuing to operate.
6. When using any attachment, never direct the discharge of
material toward bystanders or allow anyone near the machine
while in operation.
7. Start the engine when the blade control bar is in the neutral lock
position, and the drive control bar is disengaged.
8. If the mower discharge ever plugs, shut off the engine, remove
the spark plug wire, and wait for all movement to stop before
removing the obstruction.
WARNING
DO NOT use your hand to dislodge the clogged
discharge chute. Use a stick or other device to
remove clogged material after the engine has
stopped running and the blade has stopped
turning.
9. Be alert for holes, rocks, roots and other hidden hazards in the
terrain. Use caution when operating near drop-offs. Beware of
overhead obstructions (low limbs, etc.), underground obstacles
(sprinklers, pipes, tree roots, etc.). Cautiously enter a new area.
Be alert for hidden hazards.
10. Disengage power to cutter deck before backing up. Do not
mow in reverse unless absolutely necessary and then only after
observation of the entire area behind the mower. If you must
mow in reverse, maintain a constant lookout to the rear of the
machine and mow slowly.