Diamond Products Fast-Cut FC7312 User manual

Instruction Manual
Important:
Read this instruction manual carefully before putting the Fast-Cut into operation and strictly observe the safety regulations!
Improper use can cause serious injury! Keep this instruction manual!
WARNING!
FUELS WITH MORE THAN 10% ETHANOL ARE NOT APPROVED FOR USE IN DIAMOND PRODUCTS
2-STROKE ENGINES!
Use of alternative fuels, such as E-20 (20% ethanol), E-85 (85% ethanol) or any fuels not meeting Diamond Products
requirements are not approved for use in Diamond Products 2-stroke gasoline engines!
USE OF ALTERNATIVE FUELS CAN CAUSE THE FOLLOWING PROBLEMS:
Poor engine performance, loss of power, overheating, fuel vapor lock, improper clutch engagement, premature
deterioration of fuel lines, premature deterioration of gaskets, premature deterioration of carburetors.
USING ALTERNATIVE FUELS AND/OR 2-STROKE OILS NOT ACCORDING TO JASO FC OR ISO-L-EGD IN
DIAMOND PRODUCTS 2-STROKE ENGINES WILL VOID YOUR ENGINE WARRANTY!
Model FC7312
Model FC7314
Model SC-8116XL

2
EMISSIONS COMPONENT DEFECT WARRANTY COVERAGE
Diamond Products, 333 Prospect Street, Elyria, OH 44035, (herein “Diamond Products”) warrant(“s”) to the initial retail purchaser
and each subsequent owner, that this non-road engine (herein „engine“) has been designed, built, and equipped to conform at the
time of initial sale to all applicable regulations of the U.S.
Environmental Protection Agency (EPA), and that the engine is free of defects in materials and workmanship which would cause this
engine to fail to conform with EPA regulations during its warranty period.
For the components listed under PARTS COVERED, the service dealer authorized by Diamond Products will, at no cost to you, make the
necessary diagnosis, repair, or replacement necessary to ensure that the engine complies with applicable U.S. EPA regulations.
EMISSION COMPONENT DEFECT WARRANTY PERIOD
The warranty period for this engine begins on the date of sale to the initial purchaser and continues for a period of 2 years.
PARTS COVERED
Listed below are the parts covered by the Emission Components Defect Warranty. Some of the parts listed below may require
scheduled maintenance and are warranted up to the rst scheduled replacement point for that part.
Fuel Metering System Ignition System
Carburetor and internal parts Spark plugs
Fuel lter, if applicable Flywheel Magneto
Throttle stopper, if applicable Ignition Coil
Choke System, if applicable
Air Induction System Miscellaneous Items Used in Above Systems
Air cleaner plate, Air lter Fuel hoses, clamps and sealing gaskets
Air cleaner case, Intake manifold
Components with evaporative emissions
Fuel tank, Fuel tank cap
OBTAINING WARRANTY SERVICE
To obtain warranty service, take your engine to the nearest authorized Diamond Products service dealer. Bring your sales receipts
indicating date of purchase for this engine. The service dealer authorized by Diamond Products will perform the necessary repairs or
adjustments within a reasonable amount of time and furnish you with a copy of the repair order. All parts and accessories replaced
under this warranty become the property of Diamond Products.
WHAT IS NOT COVERED
• Conditions resulting from tampering, misuse, improper adjustment (unless they were made by the service dealer authorized by
Diamond Products during a warranty repair), alteration, accident, failure to use the recommended fuel and oil, or not performing
required maintenance services.
• The replacement parts used for required maintenance services.
• Consequential damages such as loss of time, inconvenience, loss of use of the engine or equipment, etc.
• Diagnosis and inspection charges that do not result in warranty-eligible service being performed.
• Any non-authorized replacement part, or malfunction of authorized parts due to use of non-authorized parts.
OWNER’S WARRANTY RESPONSIBILITIES
As the engine owner, you are responsible for the performance of the required maintenance listed in your owner’s manual. Diamond
Products recommends that you retain all receipts covering maintenance on your engine, but Diamond Products cannot deny war-
ranty solely for the lack of receipts or for your failure to ensure the performance of all scheduled maintenance. As the engine owner,
you should however be aware that Diamond Products may deny warranty coverage if your engine or a part has failed due to abuse,
neglect, improper maintenance or unapproved modications.
You are responsible for presenting your engine to the nearest service dealer authorized by Diamond Products when a problem ex-
ists.
If you have any questions regarding your warranty rights and responsibilities, you should contact the Diamond Products Product
Support Department (U.S.A. 1-800-321-5336) for the information.
THINGS YOU SHOULD KNOW ABOUT THE EMISSION CONTROL SYSTEM WARRANTY:
MAINTENANCE AND REPAIRS
You are responsible for the proper maintenance of the engine. You should keep all receipts and maintenance records covering the
performance of regular maintenance in the event questions arise. These receipts and maintenance records should be transferred to
each subsequent owner of the engine. Diamond Products reserves the right to deny warranty coverage if the engine has not been
properly maintained. Warranty claims will not be denied, however, solely because of the lack of required maintenance or failure to
keep maintenance records.
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 SERVICE
DEALER AUTHORIZED BY Diamond Products. THE USE OF PARTS THAT ARE NOT EQUIVALENT IN PERFORMANCE AND
DURABILITY TO AUTHORIZED PARTS MAY IMPAIR THE EFFECTIVENESS OF THE EMISSION CONTROL SYSTEM AND MAY
HAVE A BEARING ON THE OUTCOME OF A WARRANTY CLAIM.
If other than the parts authorized by Diamond Products are used for maintenance replacements or for the repair of components
affecting emission control, you should assure yourself that such parts are warranted by their manufacturer to be equivalent to the
parts authorized by Diamond Products in their performance and durability.
HOW TO MAKE A CLAIM
All repair qualifying under this limited warranty must be performed by a service dealer authorized by Diamond Products. In the event
that any emission-related part is found to be defective during the warranty period, you shall notify Diamond Products Product Support
Department (U.S.A. 1-800-321-5336) and you will be advised of the appropriate warranty service dealer or service providers where
the warranty repair can be performed.

3
Thank you for purchasing Diamond Products!
Congratulations on choosing a Diamond Products Fast-Cut cutoff
saw! We are condent that you will be satised with this modern
piece of equipment. The Diamond Products Fast-Cut features
specially designed high-performance engine with outstanding
power-to-weight ratios, for heavy-duty yet lightweight tools.
Other advantages of the Diamond Products Fast-Cut:
• Sturdy construction and high reliability.
• Maintenance‑free electronic ignition, hermetically sealed to
protect against dust and moisture.
• Vibration damping with the Diamond Products 2-mass system
(D2M) for tireless working even when guiding the Fast‑Cut by
hand.
• Five‑stage air‑lter system for reliable working even under very
dusty conditions.
• Two options for mounting the cutter attachment: Either centrally,
for good balance when guiding the unit manually, or on the side,
for ush cuts along walls or curbsides or horizontally directly
above the ground.
• Extensive range of resin-bonded and diamond grit cutting discs,
trolley with dust catcher, and systems for supplying water to the
disc.
The following industrial property rights apply:
US 08510690, SE 95027298, SE 95027306, IT 95000653,
IT 95000654, GBM 9412558, GBM 9412559.
We want you to be satised with your Diamond Products prod-
uct.
In order to guarantee the optimal function and performance of your
Fast-Cut and to ensure your personal safety we would request you
to perform the following:
Read this instruction manual carefully before putting the
Fast-Cut into operation for the rst time, and strictly observe
the safety regulations! Failure to observe these precautions
can lead to severe injury or death!
Only for FC7312, FC7314: The Emissions Compliance Period
referred to on the emission Compliance label indicates the num-
ber of operating hours for which the engine has been shown to
meet federal emissions requirements.
Category C= 50 hours, B= 125 hours, and A= 300 hours.
Packing
Your Diamond Products Fast-Cut is packed in a cardboard box
to prevent shipping damage.
Cardboard is a basic raw material and is consequently reuseable
or suitable for recycling (waste paper recycling).
Table of contents Page
Packing ................................................................................ 3
Delivery inventory .............................................................. 4
Symbols ............................................................................... 4
SAFETY PRECAUTIONS
Intended use ................................................................... 5
General precautions ....................................................... 5
Protective equipment ...................................................5-6
Fuels / Refuelling ............................................................ 6
Putting into operation ...................................................... 6
Cutting discs ................................................................... 7
Kickback and lock-in ....................................................... 8
Working behavior / Method of working ............................ 8
Always observe the following when using
synthetic resin cutting discs ............................................. 9
Cutting metal ................................................................... 9
Cutting masonry and concrete ...................................9-10
Transport and storage ................................................... 10
Maintenance ................................................................. 11
First aid ......................................................................... 11
Disposal and environmental protection ......................... 11
Technical data ................................................................... 12
Denomination of components ......................................... 13
PUTTING INTO OPERATION
Mounting the cutting disc ............................................... 14
Tightening the V-belt / Checking V-belt tension ............15
Installing the pressure water system .......................15-16
Fuels / Refuelling .....................................................16-17
Starting the engine ........................................................ 18
Cold-starting ................................................................. 19
Warm-starting ............................................................... 19
Stop engine ................................................................... 19
Adjusting the carburetor .................................................. 20
MAINTENANCE
Changing the V-belt ...................................................... 21
Cleaning the protection hood ........................................ 22
Cleaning / changing the air lter ..............................22-23
Replacing the spark plug ..............................................24
Replacing the suction head .......................................... 24
Replacing the starter cable ........................................... 25
Replacing the return spring ........................................... 26
Instructions for periodic maintenance ........................... 30
Cutting attachment in central / side position ................. 27
Repositioning the cutting attachment .......................27-28
Replacing/cleaning the spark arrester screen .............. 28
Service, spare parts and guarantee ...........................29-30
Troubleshooting ............................................................... 30

4
Delivery inventory
1. Fast-Cut
2. Adapter ring 0.8"/1.0" (not in the general scope of delivery. Country‑specic)
3. Screwdriver (for carburetor adjustment)
4. Offset screwdriver
5. Universal wrench 13/19
7. Instruction manual (not shown)
Symbols
You will notice the following symbols on the Fast‑Cut and in the Instruction Manual:
In case one of the parts listed should not be included in the
delivery inventory, please consult your sales agent.
Never use carbide tipped, circular saw
blades or any kind of wood cutting
blades!
Combination Start/Stop (I/O) switch,
choke
Starting procedure
(Press decompression valve,
Engine - manual start)
Stop engine!
Warning!
Kickback!
Fuel and oil mixture
First aid
Recycling
Do not touch hot surfaces!
Read instruction manual and
follow the warning- and safety
precautions!
Particular care and caution!
Forbidden!
Wear helmet and eye, respiratory
and hearing protection!
Wear protective gloves!
Wear respiratory protection!
Hazardous dust and/or
gas emission!
Fire hazard from ying sparks!
No smoking!
No open re!
Direction of cutting wheel rotation
Warning: the max. peripheral
speed of the cutting disc is 80 m/s!
Cutting disc dimensions
5 4 3 2 1

5
2
3
1
4
SAFETY PRECAUTIONS
Intended use
Fast-Cut
Use the Fast-Cut cutoff saw outdoors only, for trimming and cutting
suitable materials, using cutting discs rated for this machine.
Improper use:
Never use the cutoff saw cutting discs for grinding or sanding (using
the side of the cutting disc to remove material). The disc can break!
Never use the Fast‑Cut with saw blades, cutter blades, brushes,
carbide tipped, wood cutting blades etc.
Unauthorised users:
Persons unfamiliar with the Instruction Manual, children, young
people, and persons under the inuence of alcohol, drugs or medi-
cations must not use the Fast-Cut.
General precautions
-The operator MUST read this instruction manual to ensure
safe operation (even if you already have experience in us-
ing cutoff saws). It is important to be familiar with the opera-
tion of this particular cutoff saw. Users insufciently informed
will endanger themselves as well as others due to improper
handling.
- Let only persons who have experience in using cutoff saws work
with this unit. When letting another person use the Fast-Cut,
this instruction manual must be provided along with it.
- First-time operators should ask a specialist to instruct them in
working with gasoline-powered cutoff saws.
- Children and persons under 18 years of age must not be allowed
to use this Fast-Cut. Persons over the age of 16 years may,
however, use the Fast-Cut for the purpose of being trained as
long as they are under the supervision of a qualied trainer.
- Working with the Fast-Cut requires high concentration.
- Operate the Fast-Cut only if you are in good physical condition.
If you are tired, your attention will be reduced. Be especially
careful at the end of a working day. Perform all work calmly and
carefully. The user has to accept liability for others.
‑ Never work while under the inuence of alcohol, drugs, medica-
tion or other substances which may impair vision, dexterity or
judgement.
‑ A re extinguisher must be available in the immediate vicinity
when working in easily inammable vegetation or when it has
not rained for a long time (danger of re).
- Asbestos and other materials that can release toxins may be cut
only with the necessary safety precautions and after notication
of the proper authorities and under their supervision or that of
a person appointed by them.
- The use of dust-reduction devices is urgently recommended
(see Accessories, pressure water tank, water tank).
Protective equipment
- In order to avoid head, eye, hand or foot injuries as well as
to protect your hearing the following protective equipment
must be used during operation of the Fast-Cut:
- The kind of clothing should be appropriate, i. e. it should be tight-
tting but not be a hindrance. Clothing in which grains of material
can accumulate (trousers with cuffs, jackets and trousers with
wide-open pockets, etc.) must not be worn, particularly when
cutting metal.
- Do not wear any jewellery or clothing that can get caught or
distract from the operation of the Fast-Cut.
- It is necessary to wear a protective helmet whenever working
with the Fast-Cut. The protective helmet (A) is to be checked
in regular intervals for damage and is to be replaced after 5
years at the latest. Use only approved protective helmets.
- The helmet visor (B) protects the face from dust and material
grains. In order to prevent injuries to eyes and face, always wear
protective goggles (C) or visor when using the Fast-Cut.
- To prevent hearing damage, always wear suitable personal
hearing protection. (ear muffs (D), ear plugs, etc.). Octave
brand analysis upon request.
- When dry-cutting dust-producing materials such as stone
or concrete, always wear approved respiratory protection
(E).
- Work gloves (F) of tough leather are part of the required
work kit of the Fast-Cut and must always be worn when
working with the Fast-Cut.

6
- Always wear safety shoes or boots (G) with steel toes, non‑skid
soles, and leg protectors when working with the Fast-Cut. Safety
shoes equipped with a protective layer provide protection against
cuts and ensure a secure footing.
- Always wear a work suit (H) of tough material with sufcient
ame‑retardant qualities whenever working with the cutoff
saw.
Fuels / Refuelling
‑ Go to a safe, level place before refuelling. Never refuel while
on scaffolding, on heaps of material, or in similar places!
- Switch off the engine before refuelling the Fast-Cut.
‑ Do not smoke or work near open res (6).
- Let the engine cool down before refuelling.
- Fuels can contain substances similar to solvents. Eyes and skin
should not come in contact with mineral oil products.Always wear
protective gloves when refuelling (not the regular work gloves!).
Frequently clean and change protective clothes. Do not breathe
in fuel vapors. Inhalation of fuel vapours can be hazardous to
your health.
- Do not spill fuel. If a spill occurs, clean off the Fast-Cut imme-
diately. Fuel should not come in contact with clothes. If your
clothes have come in contact with fuel, change them at once.
- Ensure that no fuel oozes into the soil (environmental protection).
Use an appropriate base.
- Refuelling is not allowed in closed rooms. Fuel vapors will ac-
cumulate near the oor (explosion hazard).
‑ Ensure to rmly tighten the screw cap of the fuel tank.
- Before starting the engine, move to a location at least 3 meters
(approx. 10 feet) from where you fuelled the Fast-Cut (7), but
not within the extended swing range of the cutting disc (direction
of sparks).
- Fuel cannot be stored for an unlimited period of time. Buy only
as much as will be consumed in the near future.
- When making up the gasoline/oil mixture, always put the oil in
the mixing container rst, and then the gasoline.
- Use only approved and marked containers for the transport and
storage of fuel.
- Keep fuel away from children!
Putting into operation
- Do not work on your own. There must be someone around
in case of an emergency (within shouting distance).
- Observe all anti-noise regulations when working in residential
areas.
- Never use the Fast-Cut near inammable materials or ex-
plosive gases! The Fast-Cut can create sparks leading to
re or explosion!
‑ Make sure that all persons within 30 meters (100 feet), such
as other workers, are wearing protective gear (see "Protective
Equipment") (8). Children and other unauthorized persons must
remain more than 30 meters away from the working area. Keep
an eye out for animals as well (9).
- Before starting work the Fast-Cut must be checked for
perfect function and operating safety according to the pre-
scriptions. In particular, make sure that the cutting wheel is in
good condition(replace immediately if torn, damaged or bent),
the cutting wheel is properly mounted, the protective hood is
locked in place, the hand guard is properly mounted, the V-belt
has the proper tension, the throttle moves easily and the half-
throttle lock button functions properly, the grips are clean and
dry, and the combination switch functions properly (Start/Stop
(I/O) switch, choke). Visually inspect the mufer for damage and
possible dirt in the mufer area.
- Start the Fast-Cut only after complete assembly and inspection.
Never use the Fast‑Cut when it is not completely assembled.
7
6
5
9
8= wearing Protective Equipment
10 feet
(3 meters)
100 feet (30 meters)

7
Cutoff discs
- The protection hood must always be on! Change discs only
with the engine off!
- There are two basic types of cutoff discs:
- For metal (hot cutting)
- For masonry (cold cutting)
WARNING!
Never use carbide tipped, circular saw blades or any kind of wood
cutting blades. Never cut any type of wood. Reactive forces can
cause severe personal injury from blade contact or thrown tips.
NOTE: When using diamond cutoff discs, always make sure to observe
the "direction of rotation" markings. Diamond discs should only be
used for cutting masonry/brick/ concrete etc.
- Cutoff discs are intended only for radial loading, i.e. for cutting. Do
not grind with the sides of the cutting disc! This will break the disc
(10)!
Caution!
Never change direction (turning radius less than 5 meters (16
feet), exert lateral (sideways) pressure, or tip the Fast-Cut during
cutting (11)!
- Use a cutting disc only for cutting the materials it is intended for. The
proper type of disc must be used, for either metals or masonry.
‑ The arbor hole of the cutting disc must be an exact t with the arbor
or shaft. If the arbor hole is larger, it must be tted with an adapter
ring (available as an accessory).
- The cutting disc must be rated for freehand cutting at up to 3850
rpm or 80 m/sec for 400 mm discs, 4370 rpm or 80 m/sec for 350
mm discs, or up to 5100 rpm or 80 m/s for 300 mm discs. Use only
cutting discs that comply with EN 12413, EN 13236.
- The disc must be free of defects (12). Do not use defective cutting
discs.
Always tighten the cutting disc mounting bolt to a torque of 30
Nm. Otherwise, the cutting disc can twist.
- Before starting the cutting disc, make sure you have a steady foot-
ing.
- Put the Fast-Cut into operation only as described in this instruction
manual (13).Always place your left foot in the rear handle and grasp
the other handle rmly (with thumb and ngers). Other starting
methods are not allowed.
- When starting the Fast-Cut it must be well supported and securely
held. The cutting disc must not be touching anything.
- If the cutting disc is new, test it by running it at least 60 seconds at
top speed.Whendoingthis,makesurethatnopersons orbody parts
are in the extended swing range of the disc, in case it is defective
and ies apart.
- Whenworking withtheFast-Cutalwaysholditwithbothhands.
Take the back handle with the right hand and the tubular handle
with the left hand. Hold the handles tightly with your thumbs facing
your ngers.
- CAUTION: When you release the throttle lever the disc will
keep spinning for a short period of time (free-wheeling effect).
- Continuously ensure that you have a safe footing.
- Hold the Fast-Cut such that you will not breathe in the
exhaust gas. Do not work in closed rooms or in deep holes
or ditches (danger of poisoning by fumes).
- WARNING – CARBON MONOXIDE PRODUCED DURING USE
CANKILL–DONOTUSEFast-CutTERINDOORS–MAKESURE
THERE IS PROPER VENTILATION WHEN USING Fast-CutTER
IN TRENCHES OR OTHER CONFINED SPACES.
- SwitchofftheFast-Cutimmediatelyifyouobserveanychanges
in its operating behavior.
- Switch off the engine before inspecting the V-belt tension or
tighteningit,replacingthecuttingwheel,repositioningthecutter
attachment (side or middle position) or eliminating faults (14).
- Turn off the engine immediately and check the disc if you hear or
feel any change in cutting behaviour.
- Turn off the Fast-Cut when taking a break or stopping work (14).
Place the unit in such a way that the disc is not touching anything
and cannot endanger anyone.
‑ Do not put the overheated Fast‑Cut in dry grass or on any inam-
mable objects. The mufer is very hot (danger of re).
- IMPORTANT: After wet cutting, rst turn off the water feed and then
let the disc run at least 30 seconds, to ing off the remaining water
and prevent corrosion.
10
11
13
12
min. 16 feet
(5 m)
14
● Maintenance
● Refuelling
● Changing cutoff discs
●Repositioning the
cutting attachment
● Stopping work
● Transport
● Putting out of function

8
Kickback and lock-in
- When working with the Fast-Cut there is a danger of kickback
and lock-in.
- Kickback occurs when the top of the cutting disc is used for
cutting (15).
- This causes the Fast-Cut to be thrown back toward the user
with great force and out of control. Risk of injury!
To prevent kickback, observe the following:
‑ Never cut with the section of the cutting disc shown in gure 15.
Be especially careful when reinserting the disc into cuts
that have already been started!
- Lock-in occurs when the cut narrows (crack, or workpiece under
stress).
- This causes the Fast-Cut to suddenly jump forward, out of
control and with great force. Risk of injury!
To prevent lock-in, observe the following:
- When reinserting the disc into previous cuts, have the Fast-Cut
running at top speed. Always cut at top speed.
- Always support the workpiece so that the cut is under tension
(16), so that the cut does not press together and jam the cutting
disc as it proceeds through the material.
- When starting a cut, apply the disc to the workpiece with care.
Do not just shove it into the material.
‑ Never cut more than one piece at a time! When cutting, make
sure that no other workpiece comes into contact.
Working behavior / Method of working
- Before starting work, check the work area for any hazards
(electrical wires, inammable substances). Clearly mark the
work area (for example with warning signs or by cordoning off
the area).
‑ When working with the Fast‑Cut hold it rmly by the front and
rear handles. Never leave the Fast‑Cut unattended!
- Use the Fast-Cut at high speed as far as possible (see “Techni-
cal Data”).
- Only use the Fast-Cut during good light and visibility periods.
Be aware of slippery or wet areas, and of ice and snow (risk of
slipping).
‑ Never work on unstable surfaces. Make sure that there are no
obstacles in the working area, risk of stumbling. Always ensure
that you have a safe footing.
‑ Never cut above your shoulder height (17).
‑ Never stand on a ladder to cut (17).
‑ Never use the Fast‑Cut while standing on scaffolding.
- Do not lean over too far when working. When putting down and
picking up the Fast-Cut, do not bend over from the waist, but
instead bend in the knees. Save your back!
‑ Guide the Fast‑Cut in such a way that no part of your body is
within the extended swing range of the disc (18).
- Use cutting discs only for the materials for which they are de-
signed!
- Use cutting discs only for the materials for which they are
designed. Do not use the Fast-Cut to lift up and shovel away
pieces of material and other objects.
Important! Before cutting, remove all foreign objects, such as
rocks, gravel, nails etc. from the cutting area. Otherwise, such
objects can be ung away by the disc with great speed. Injury
hazard!
‑ When cutting workpieces down to length use a rm support.
If necessary, secure the workpiece from slipping, but do not
steady it with your foot or allow another person to hold it.
- When cutting round items, always secure them against rota-
tion.
- When guiding the Fast-Cut by hand, use the side mounting
position of the cutter attachment only when actually necessary.
Otherwise, always use the central position. This gives the unit
a better balance, for reduced operator fatigue. 18
16
17
15

9
When using synthetic resin cutting discs, always ob-
serve the following:
CAUTION:
- Synthetic resin cutting discs can absorb moisture. This
moisture can cause the disc to become unbalanced at high
speed. This imbalance can cause the disc to break.
- Do not cool resin cutting discs with water or other uids.
- Do not expose resin cutting discs to high humidity or
rain!
Do not use resin cutting discs past their use-by date (expira-
tion date)! The date (quarter and year) is stamped on the disc’s
arbor ring.
EXAMPLE: 04 / 2013
This cutting disc can be used through the end of the fourth quarter
of 2013, if properly stored and correctly used.
Cutting metals
IMPORTANT!
Always wear approved respiratory protection!
Materials that can release toxic substances may be cut only
after notifying the proper authorities and under their supervi-
sion or that of a person appointed by them.
CAUTION!
The rapid rotation of the cutting disc heats metal and melts it
at the point of contact. Swing the guard as far down as pos-
sible (19) in order to direct the stream of sparks forward, away
from the operator (re hazard).
- Determine the cut line, mark the cut and apply the disc to the
material at moderate speed, to cut a guide groove before going
to top speed and applying more pressure to the Fast-Cut.
- Keep the disc straight and vertical. Do not tip it, as this can
break it.
- The best way to get a good, clean cut is to pull or move the
Fast-Cut back and forth. Do not simply press the disc into the
material.
- Thick round stock is best cut in stages (20).
- Thin tubing and pipes can be cut with a simple downward
cut.
- Cut large-diameter pipes as for round stock. To prevent tipping
and for better control, do not let the disc sink too deeply into
the material. Instead, always cut shallow around the whole
piece.
- Worn discs have a smaller diameter than new discs, so that at
the same engine speed they have a lower effective circumfer-
ential speed and therefore do not cut as well.
‑ Cut I‑beams and L‑bars in steps; see Figure 21.
- Cut bands and plates like pipes: along the wide side with a long
cut.
- When cutting material under stress (supported material or mate-
rial in structures), always make a notch in the thrust (pressure)
side, and then cut from the tension side, so that the disc does
not lock in. Secure cutoff material from falling!
CAUTION!
If there is a chance that the material is under stress, be pre-
pared for it to kick back. Make sure you can get out of the
way if you have to!
Be particularly careful in scrap-metal yards, junkyards, at ac-
cident sites, and with haphazard piles of material. Precariously
balanced pieces or pieces under stress can act in unpredictable
ways, and may slide, jump out, or burst. Secure cutoff material
from falling! Always exercise extreme caution and use only
equipment that is in perfect working order.
Observe the accident-prevention rules and regulations of your
employer and/or insurance organization.
19
20
21
Cutting masonry and concrete
IMPORTANT!
Always wear approved respiratory protection!
Asbestos and other materials that can release toxic sub-
stances maybe cutonlyafternotifyingtheproperauthorities
and under their supervision or that of a person appointed
by them. When cutting prestressed and reinforced concrete
piles, follow the instructions and standards of the respon-
sible authorities or the builder of the structural member.
Reinforcement rods must be cut in the prescribed sequence
and in accordance with applicable safety regulations.
NOTE:
Mortar, stone, and concrete develop large quantities of dust during
cutting. To increase the lifetime of the cutting disc (by cooling),
to improve visibility, and to avoid excessive dust creation, we
strongly recommend wet cutting instead of dry cutting.

10
In wet cutting, the disc is wetted at an equal rate on both sides
by a trickle of water. DIAMOND offers the right accessories for all
wet cutting applications.
- Remove foreign objects such as sand, stones and nails found
within the working area. Caution: Watch out for electric wires
and cables!
The rapid rotation of the cutting disc at the point of contact
throws fragments out of the cut groove at high speed. For
your safety, swing the protection hood down as far as pos-
sible (23), so that material fragments are thrown forward,
away from the operator.
‑ Mark the cut, and then make a groove about 5 mm (just under
1/5") along the entire length of the planned cut. This groove will
then guide the Fast-Cut accurately guring the actual cutoff.
NOTE:
For long, straight cuts we recommend using a trolley (24). This
makes it much easier to guide the unit straight.
- Perform the cut with a steady back-and-forth motion.
- When cutting slabs to size, you need not cut through the entire
material thickness (creating unnecessary dust). Instead, simply
make a shallow groove, and then knock off the excess material
cleanly on a at surface (25).
CAREFUL!
When cutting into lengths, cutting through material, making cutouts,
etc., always make sure to plan the direction and sequence of cuts
in such a way that the disc does not get jammed by the cut-off
piece, and that no persons can be injured by falling pieces.
Transport and storage
- Always turn off the Fast-Cut when transporting it or mov-
ing it from place to place on a site (26).
- Never carry or move the unit with the engine on or the
disc moving!
- Carry the unit only by the tubular (middle) handle with the cut-
ting disc pointing behind you (26). Avoid touching the exhaust
mufer (burn hazard!)
- When moving the Fast-Cut over longer distances, use a
wheelbarrow or wagon.
- When transporting the Fast-Cut in a vehicle, make sure it is
securely positioned in such a way that no fuel can leak out.
Always remove the cutting disc before transporting the unit in
a vehicle. Before transporting in a vehicle, allow the Fast-Cut
to cool off completely. Note: Mufers with catalytic converters
take longer to cool off!
- The Fast-Cut should be stored safely in a dry place. It must
not be left outdoors! Always dismount the cutting disc before
storage. Keep the Fast-Cut away from children.
- Before long-term storage andbefore shipping the Fast-Cut,
follow the instructions in the chapter on "Periodic care
and maintenance". ALWAYS empty the fuel tank and run
the carburetor dry.
- When putting cutting discs in storage, be careful to:
• Clean and dry them well. CAUTION: Do NOT clean synthetic
resin cutting discs with water or other uids!
• Store them lying down at.
• Avoid dampness, freezing temperatures, direct sunshine,
high temperatures and temperature uctuations, as these
can cause breakage and splintering.
• Before re-using a resin cutting disc, make sure of the use-by
(expiration) date (quarter and year, stamped on the arbor
ring). If this date has been exceeded, do NOT use the cutting
disc.
- Always check new cutting discs or cutting discs that have
been in storage to make sure that they are free of defects
and before the rst cut test‑run the tool at top speed for at
least 60 seconds. Keep body parts and people well away out
of range of the direction of the cutting disc during this test.
23
26
25
24

11
Maintenance
- Before performing maintenance work switch off the Fast-
Cut (27) and pull out the plug cap.
- Allowthe Fast-Cutto cooloffbeforedoing anymaintenance
work (burn hazard)!
- Fast-Cuts with catalytic converter take longer to cool
down!
- Always check the Fast-Cut before using it to make sure that
it is in good working order. In particular, make sure that the
cutting disc is properly mounted. Make sure that the cutting
wheel is undamaged and suitable for the job it will be used
for.
- Operate the Fast-Cut only at a low noise and emission level.
For this ensure the carburetor is adjusted correctly.
‑ Do not operate the Fast‑Cut with a defective or modied muf-
er.
- Clean the Fast-Cut regularly.
- Check the fuel tank cap regularly for good sealing.
Observe the accident prevention instructions issued by
trade associations and insurance companies. NEVER
make any modications to the Fast-Cut! You will only be
putting your own safety at risk!
Perform only the maintenance and repair works described in
the instruction manual. All other work must be carried out by
Diamond Products Service.
Use only original Diamond Products spares and accesso-
ries.
The use of non-Diamond Products spares, accessories, or
cutting discs increases the risk of accident. We cannot ac-
cept any responsibility for accidents or damage occurring in
association with the use of cutting discs or accessories other
than original Diamond Products.
First aid
For the event of a possible accident, please make sure that a
rst aid kit is always immediately available close by. Immediately
replace any items used from the rst aid box.
When calling for help, give the following information:
- Place of the accident
- What happened
‑ Number of injured people
- Kind of injuries
- Your name!
NOTE
Individuals with poor circulation who are exposed to excessive
vibration may experience injury to blood vessels or the nervous
system.
Vibration may cause the following symptoms to occur in the n-
gers, hands or wrists: ”Falling asleep” (numbness), tingling, pain,
stabbing sensation, alteration of skin colour or of the skin. If any
of these symptoms occur, see a physician!
Disposal and environmental protection
Be mindful of the environment!
Dispose of worn-out or defective cutting discs in accordance with
your local disposal regulations. To protect unusable cutting discs
from misuse, destroy them before disposal.
When the Fast-Cut is worn out or damaged beyond repair, have
it disposed of or recycled in an environmentally sound manner. If
necessary, consult your local authorities.
27
28
29
SERVICE

12
Technical data
Displacement cu in (cm3)4.5 (73) 4.5 (73)
Bore in (mm) 1.97 (50) 1.97 (50)
Stroke in (mm) 1.46 (37) 1.46 (37)
Max. power hp (kW) 5.1 (3.8) 5.1 (3.8)
Max. torque Nm 4.3 4.3
Idling speed 1/min 2,500 2,500
Clutch engagement speed 1/min 3,800 3,800
Engine speed limitation 1/min 9,400 ± 145 9,400 ± 145
Max. spindle speed 1/min 4,300 4,300
Sound pressure level at the operators ear dB(A) 100 100
Sound pressure level at the bystander’s position (50 ft) dB(A) 79 79
Vibration acceleration ah,w per ANSI.175.4
- Tubular handle (rated speed) m/s2 6.2 6.2
- Rear handle (rated speed) m/s24.4 4.4
Carburetor (diaphragm carburetor) Type WALBRO WJ-126
Ignition system (with speed limitation) Type electronic
Spark plug Type
NGK BPMR 7A / BOSCH WSR 6F / CHAMPION RCJ 6Y
Electrode gap in (mm) .020 (0.5) .020 (0.5)
Fuel consumption at max. load per ISO 8893 kg/h 1.7 1.7
Specic consumption at max. load per ISO 8893 g/kWh 450 450
Fuel tank capacity  oz (l) 37 (1.1) 37 (1.1)
Mixture ratio (fuel/two‑stroke oil) 5) 50:1 50:1
Cutting disc for 80 m/sec. 2) in 12" / 0.8" / 0.2" 3) 14" / 0.8" / 0.2" 3)
Cutting disc for 80 m/sec. 2) 4) in 14" / 1.0" / 0.2" 3)
Arbor diameter in 0.8" 0.8" / 1.0"
V-belt no. 6060118 6060118
Overall weight (tanks empty, without cutting disc) lb 21.56 22.00
Displacement cu in (cm3)4.9 (81)
Bore in (mm) 2.05 (52)
Stroke in (mm) 1.49 (38)
Max. power hp (kW) 6.2 (4.5)
Max. torque Nm 5.2
Idling speed 1/min 2,500
Clutch engagement speed 1/min 3,800
Engine speed limitation 1/min 9,350 ± 145
Max. spindle speed 1/min 4,300
Sound pressure level at the operators ear dB(A) 100
Sound pressure level at the bystander’s position (50 ft) dB(A) 79
Vibration acceleration ah,w per ANSI.175.4
- Tubular handle (rated speed) m/s28.1
- Rear handle (rated speed) m/s26.1
Carburetor (diaphragm carburetor) Type WALBRO WJ-126
Ignition system (with speed limitation) Type electronic
Spark plug Type
NGK BPMR 7A / BOSCH WSR 6F / CHAMPION RCJ 6Y
Electrode gap in (mm) .020 (0.5)
Fuel consumption at max. load per ISO 8893 kg/h 2.3
Specic consumption at max. load per ISO 8893 g/kWh 500
Fuel tank capacity  oz (l) 37 (1.1)
Mixture ratio (fuel/two‑stroke oil) 5) 50:1
Cutting disc for 80 m/sec. 2) in 16" / 0.8" / 0.2" 3)
Cutting disc for 80 m/sec. 2) 4) in 16" / 1.0" / 0.2" 3)
Arbor diameter in 0.8" (1.0") 4)
V-belt no. 6060373
Overall weight (tanks empty, without cutting disc) lb 23.37
2) Circumference speed at max. engine speed
3) Outside diameter / arbor hole / thickness
4) Country‑specic
5) Quality grade JASO FC or ISO‑L‑EGD specications.
SC-8116XL
FC7312 FC7314

13
Denomination of components (Illustration shows model FC7314)
1 Handle
2 Filter cover for air lter and spark plug cap
3 Cover lock
4Tubular handle
5 Mufer
6 Protection hood
7 Grip
8V-belt tension adjusting screw
9Retaining nuts
10 Stand
11 Carburetor adjustment opening
12 Identication plate
13 Fuel tank with handle
14 Decompression valve
15 Starter grip
16 Air intake
17 Combination switch „Choke, Start/Stop (I/O)”
18 Safety locking button
19 Throttle lever
20 Tank cap (fuel)
21 Starter housing with starter
22 Cutting disc
23 Disc bolt
24 Spring washer
25 Hold opening
1
2
3 4 5 6 7
8
25
9
1012 111314
24
23
17
22
18
19
20
21
15 16

14
Place the spring washer (8) on the arbour and insert the screw
(9) and tighten by hand.
Turn the disc slowly until the stop hole of the V-belt pulley is
visible in the cutting arm cover (10).
Insert the Allen key (2) as far as it will go. The shaft is now
blocked.
Tighten the screw with the combination wrench (1)
NOTE: Tighten the screw rmly (30 ± 2 Nm), as otherwise
the cutting wheel may slip during cutting.
Mounting the cutting disc
Inspect the disc for damage.
See SAFETY INSTRUCTIONS, Page 7.
Unscrew screw (9) and remove the spring washer (8).
Place the cutting disc (5) on the arbour (7).
NOTE: The arbor hole of the cutting disc must be an exact t
with the arbor or shaft. If the arbor hole is larger, it must be tted
with an adapter ring (*).
Make sure the cutting disc is installed so it turns in the right
direction, if a direction is marked on the disc.
PUTTING INTO OPERATION
CAUTION:
Always turn off the engine and pull off the spark plug cap
before doing any work on the Fast-Cut! Always wear pro-
tective gloves!
CAUTION:
Start the Fast-Cut only after complete assembly and in-
spection.
Sequence
For the the following work, use the assembly tools included
with delivery:
1. 13/19 AF combination wrench
2. Allen key
3. Carburetor adjustment screwdriver
4. Adapter ring (not in the general delivery inventory)
Place the Fast-Cut on a stable surface and carry out the
following assembly steps:
Only for models SC-8116XL
No air lter is installed!
Before operation, insert an oiled foam
lter (pre-lter), as shown in the adja-
cent illustration! To do this, take off the
lter cover (see the chapter on Cleaning
/ changing the air lter). Before taking the
foam lter out of the package, knead it thoroughly.

15
NOTE: The two fastening nuts (11) must be loosened before
tightening the V-belt or checking the tension.
To increase the belt tension, turn the tightening screw (12) to
the right (clockwise) with the combination wrench included with
the Fast-Cut.
The belt tension is correctly adjusted when the nut (13) is cen-
tred on the mark (14).
IMPORTANT:
After tightening/inspection, make certain to tighten
the fastening nuts (11) (30 ± 2 Nm).
Tightening the V-belt /
Checking V-belt tension
IMPORTANT:
Exact V-belt tension is essential for maximum cutting per-
formance with minimum fuel consumption. Improper V-belt
tension will result in premature wear to the V-belt and V-belt
wheel or damage to the clutch bearing.
If the Fast-Cut is new or the V-belt has been replaced, re-
tighten the V-belt after the rst hour of operation!
15
16
18 *
17 19
21 21
17
20
Installing the pressure water system
Not in the general scope of delivery. Country-specic!
CAUTION: Before doing any work on the Fast-Cut,
always switch off the engine and disconnect the
spark plug cap!
NOTE: When using a protective hood for a maximum disk diam-
eter of 300 mm (12"), always shorten hose (15) to 180 mm (7").
To do this unscrew sleeve (16) and carefully pull tube (15) off
coupling (17) and cut to 180 mm. Then push the tube end back
over the coupling and tighten the sleeve all the way.
‑ Install the water connection as shown in gure. Push clamp
(22) around the front grip (23) and fasten with the bolt and
square nut.
- Pull the quick-release coupling (24) from the water connection
and connect it to the 1/2" supply line (18).
- Remove the cutting disk (see instruction manual).
- Tube routing with the cutting assembly in the middle position,
see gure.
- Tube routing with the cutting assembly in the outside position,
see gure.
- Insert the nozzles (19) through the protective hood (20) from
the inside and put on couplings (17). Screw on and tighten
the coupling caps (21).
IMPORTANT:
To avoid bending the tubes, be sure to position the couplings (17)
in accordance with gures as appropriate.
- Install the cutting disc (see instruction manual).
- Connect the quick-release coupling (24) to the supply tube.
NOTE:
The water ow rate can be precisely adjusted with valve (25).

16
Fuels
Caution:
This tool uses petroleum products (gasoline and oil).
Be especially careful when handling gasoline.
Do not smoke. Do not allow gasoline to come near ames,
sparks or re (explosion hazard).
Fuel mixture
This tool is powered by a high-performance air-cooled two-stroke
engine. It runs on a mixture of gasoline and two-stroke engine
oil.
The engine is designed for unleaded regular gasoline with a
min. octane value of 91 (R+M)/2. In case no such fuel is avail-
able, you can use fuel with a higher octane value. This will not
affect the engine.
In order to obtain an optimum engine output and to protect
your health and the environment use unleaded fuel only.
To lubricate the engine, use a synthetic oil for two-stroke air-
cooled engines (quality grade JASO FC or ISO‑L‑EGD), which
has to be added to the fuel.
Gasoline 50:1
+
24 25
22
23
1.0 Us-gal. (3.7 l) 2.6 oz. (75 cm3)
2.5 Us-gal. (9.4 l) 6.4 oz. (189 cm3)
5.0 Us-gal. (18.9 l) 12.8 oz. (378 cm3)

17
Refuelling
IMPORTANT:
FOLLOW THE SAFETY PRECAUTIONS!
Be careful and cautious when handling fuels.
The engine must be turned off and cooled down!
Carefully clean the area around the fuel‑tank ller neck to keep
dirt from getting in the tank.
Place the unit on its side on an even surface.
Unscrew the tank cap and ll tank with fuel mixture. Take care
to avoid spilling.
Screw the tank cap back on hand-tight.
Clean screw cap and tank after refuelling. Never start or
operate the Fast-Cut in the same place as it was fuelled!
If fuel gets on your clothing, change clothes immediately.
Fuel mixture
AVOID SKIN AND EYE CONTACT
Mineral oil products degrease your skin. If your skin comes in
contact with these substances repeatedly and for an extended
period of time, it will dry out. Various skin deseases may result.
In addition, allergic reactions are known to occur.
Eyes can be irritated by contact with oil. If oil comes into your
eyes, immediately wash them with clear water.
If your eyes are still irritated, see a doctor immediately!
NOTE: For preparing the fuel‑oil mixture rst mix the entire oil
quantity with half of the fuel required, then add the remaining
fuel. Shake the nished mixture thoroughly before pouring it
into the tank.
Caution: Open the tank cap carefully, as pressure might
have built up inside!
It is not wise to add more engine oil than specied to
ensure safe operation. This will only result in a higher
production of combustion residues which will pollute the
environment and clog the exhaust channel in the cylinder
as well as the mufer. In addition, fuel consumption will
rise and performance will decrease.
The Storage of Fuel
Fuels have a limited storage life. Fuel and fuel mixtures
age through evaporation, especially at high temperatures.
Aged fuel and fuel mixtures can cause starting problems
and damage the engine.Purchase only that amount of fuel,
which will be consumed over the next few months. At high
temperatures, once fuel has been mixed it should be used
up in 6-8 weeks.
Use only approved and marked containers for transport
and storage. Store fuel only in dry, cool and secure
locations!

18
Starting the engine
This model is tted with a semiautomatic decompression valve
(1) to make starting easier. Press the rubber cover until you
can feel it engage. This pushes in the deompression valve
behind it. This in turn reduces the compression, so that it takes
less force to pull the starter cord to accelerate the engine to its
starting speed.
The high pressure in the combustion chamber after the rst
ignition automatically closes the decompression valve.
if
necessary
CAUTION:
Observe the SAFETY INSTRUCTIONS on page 5 and 6!
Start the Fast-Cut only after complete assembly and in-
spection!
Move at least 3m (10 feet) away from the place where you
fuelled the Fast-Cut.
Make sure you have a good footing, and place the Fast-Cut
on the ground in such a way that the cutting disc is not
touching anything.
3 meters
Move the protective hood (3) into the proper position for the
work you intend to do (see illustration).
Grasp the grip (2). The hood (3) can swing in both ways within
its range of motion.
Caution:
Always make sure that the straight outer edge of the impact plate
(4) and the edge of the hood are parallel (see arrows).
If this is not the case, take the tool to a service center.

19
Stopping the engine
Push the combination switch (6) down to position .
6
Warm starting:
As described above for cold starting, but before starting push
the combination switch (6) up (Choke position) and then right
away back to the middle “I” position.
This is only to engage the half-throttle lock. If the engine doesn’t
start after 2 or 3 pulls, repeat the entire starting procedure as
described for cold starting.
Do not leave switch in the choke position when hot
starting!
Cold starting:
Grasp front handle rmly with one hand and press the Fast‑Cut
against the ground.
Place left toe in the rear handguard.
Push the combination switch (6) up (choke position). This will
automatically activate the half-throttle lock.
NOTE: If the Fast-Cut is mounted on the trolley, do not operate
the gas lever (throttle) on the side of the trolley!
Pull the starter cable out slowly until you feel resistance (piston
is now just before top dead center).
Press in the decompression valve (5).
Pull starter cable quickly and rmly, until you hear the rst
ignition, but to a max. of 3-5 pulls!
Important: Do not pull the starter cable out more than about
50 cm / 20”, and guide it back slowly by hand (instead of letting
it snap back).
Press in the decompression valve (5).
Move the combination switch (6) to the middle “I” position.
Again pull the starter cable quickly and rmly.
As soon as the engine is running, grasp the rear handle (the
safety lock switch (8)will be depressed by the palm of your hand)
and tap the throttle (9). The half-throttle lock will be disengaged
and the engine will run in idle.
Cold start (Choke)
Warm start
Engine off
5
8
9
6

20
Adjusting
the carburetor
NOTE: The grinding parts are equipped with an electronic
ignition to limit the speed.
At the factory the idling speed has been set to approx.
2500 rpm, but the running-in process of a new engine may
require slight readjustment of the idling speed.
Adjustments to the adjusting screws (L) and (H) may only
be made by an authorised Diamond Products service
center. Accordingly, the holes for the two screws are
sealed shut.
For correct adjustment of the idling speed the following
steps must be carried out:
Start the engine and run it until it is warm (about 3 - 5
minutes).
Adjust the carburetor with the screwdriver (1, Order No. 944
340 001) included with the Fast-Cut. It has a lug that helps
with adjustment.
Readjust the idling speed.
If the cut-off disc is still turning when the engine is running,
unscrew the adjusting screw of the throttle valve (2) until the
cut-off disc is no longer turning. When the engine is left running
at idling speed, tighten the screw a little.
Switch off the engine