Jet JCT-4660, JCT-4661, 550660, 550661 Operations & Parts Manual

Pneumatic Paving Breaker

#550660, JCT-4660
#550661, JCT-4661

Operation & Parts Manual

M-550660

Edition 2

05/2017

JET

427 New Sanford Road

LaVergne, TN 37086

Ph.: 800-274-6848

www.jettools.com

Copyright © 2017 JET

Safety warnings

General air tool warnings

1. Read and understand this entire manual
before attempting assembly or operation.

2. Read and understand all warnings posted on
the tool and in this manual. Failure to comply
with all of these warnings may c ause serious
injury.

3. Replace warning labels if they become
obscured or removed.

4. Do not use this tool for other than its intended
use. If used for other purposes, JET disclaims
any real or implied warranty and holds itself
harmless from any injury that m ay result from
that use.

5. Always wear ANSI Z87.1 approved safety
glasses or face shield while using this tool.
(Everyday eyeglasses only have impact
resistant lenses; they are not safety glasses.)

6. Wear ear protectors (plugs or muffs) if the
noise exceeds safe levels.

7. Wear gloves and protective clothing if
operation produces sparks or flying particl es.
Gloves should be tight-fitting, without frayed
fingers or hanging threads. Keep hands and
body away from the working area of tool.

8. Some dust created by power sanding, sawing,
grinding, drilling and other construction
activities contains chemic als known to cause
cancer, birth defects or other reproductive
harm. Some examples of these chemicals
are:

• Lead from lead based paint.

• Crystalline silica from bricks, cement and
other masonry products.

• Arsenic and chromium from chemically
treated lumber.

Your risk of exposure varies, depending on
how often you do this type of work. To reduce
your exposure to these chemicals, work in a
well-ventilated area and work with approved
safety equipment, such as face or dust masks
that are specifically designed to filter out
microscopic particles.

9. Do not operate an air tool continually at full
throttle without a work load on the tool.

10. The air tool must be properly lubricated before
operating.

11. Never start a percussion type air tool (chipper,
breaker, buster, etc.) without securing the
tooling in the retainer and placing the tip
against the work surface.

12. Do not operate air tool without its guards in
place. Do not modify the tool.

13. Do not operate this tool while tired or under
the influence of drugs, alcohol, or any
medication.

14. Adopt a comfortable posture with proper
balance, and maintain secure footing at all
times. Non-slip footwear or anti-skid floor
strips are recommended.

15. Do not w ear loose clothing or jewelry. Confine
long hair.

16. Excessive air pressure and too much free
rotation may decrease life of the tool and may
cause a hazardous situation.

17. Check air hoses for wear, and keep them
away from heat and sharp edges. Repair or
replace damaged air hose immediately. Do
not carry tool by the air hose.

18. Air hose may cause tripping hazards; keep
hose away from traffic areas.

19. Do not use this tool near flammable objects,
or in potentially explosive environments. Do
not use near live electrical wires.

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JCT-4660 series Paving Breaker

20. Do not use power tools in damp or wet
location, or expose them to rain. Keep work
area well lighted.

21. Do not leave a connected tool unattended.
When not in use, disconnect tool from air
source.

31. Maintain tools with c are. Keep air tool clean
and oiled for best and safest performance.

32. Do not use combustible gases, carbon
dioxide, oxygen or any bottled gas as an air
source for the tool. These can present risk of
explosion and serious injury.

22. Shut off air supply and discharge any residual
pressure from tool before removing hose,
making adjustments, changing accessories,
or storing tool.

23. M ake sure tool is switched off, and your finger
off the trigger, before connecting to air supply.

24. Remove adjusting keys and wrenches before
turning on tool.

25. Keep visitors a safe distance from the work
area. Keep children away.

26. Give your work undivided attention. Looking
around, carrying on a conversation and
“horse-play” are careless acts that can result
in serious injury.

27. Do not force a tool or attachment to do a job
for which it was not designed. The right tool
will do the job better and more safely.

28. Repetitive motions and/or exposure to
constant vibration can be harmful to hands
and arms. Take frequent breaks and relax
hands during extended operation. Change
posture to avoid discomfort or fatigue.

29. Compressed air can be harmful if directed
toward sensitive areas of t he body, and may
propel small particles caught in the air stream.
Exercise proper caution.

30. Use only recommended accessories;
improper accessories may be hazardous.

33. Do not lubricate the tool with combustible
liquids, such as kerosene, diesel or jet fuel.

34. Do not dispose of this tool with normal
household waste. Never dispose of the air tool
into fire.

Specific warnings for Paving Breaker

35. This paving breaker is designed and intended
for use by properly trained and experienced
personnel only. If you are not familiar with the
proper and safe operation of a pneumatic
paving breaker, do not use until proper
training and knowledge have been obtained.

36. Use only correct steels with sharp cutting
edge. Make sure steel is securely latched in
paving breaker before pressing throttle lever.

37. Disconnect machine from air supply before
changing tooling.

38. Always hold cutting tool down firmly on the
work surface before pressing throttle lever.

39. Always grip paving breaker firmly with both
hands.

40. Apply enough downward pressure to prevent
tool from bouncing or skipping which can lead
to personal injury and tool damage.

41. Direct tool exhaust away from yourself and
others.

Familiarize yourself with the following safety notices used in this manual:

This means that if precautions are not heeded, it may result in serious, or even

fatal, injury.

This means that if precautions are not heeded, it may result in minor injury and/or

possible tool damage.

JET

3

About this manual

This manual is provided by JET, covering the safe operation and maintenance procedures for the JET Model
JCT-4660 series pneumatic Paving Breakers. This manual contains instructions on safety precautions,
general operating procedures, maintenance procedures and parts breakdown. Your tool has been designed
and constructed to provide consistent, long-t erm operation if used in accordance with the instructions s et
forth in this document.

The instructions and warnings in this manual may not encompass all possible workplace environments. The
operator is expected to take appropriate precautions and exercise common sense. As with any tool
operation, safety of operator and bystanders should be first priority.

If there are questions or comments, please contact your local supplier or JET. JET can also be reached at
our web site: www.jettools.com.

Record the serial number and purchase information of your tool on the cover of this manual for quick access.
Retain this manual for future reference. If the tool transfers ownership, the manual should accompany it.

Register your product online -

http://www.jettools.com/us/en/service-and-support/warranty/registration/

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JCT-4660 series Paving Breaker

Tool specifications

Model number JCT-4660 JCT-4661

Stock number 550660 550661
Class/type 60 lb. 90 lb.
Hex shank size 1-1/8 x 6 in. 1-1/8 x 6 in.
Piston diameter 2-1/4 in. 2-5/8 in.
Piston stroke 4 in. 6 in.
Impact rate (blows per minute) 1,400 1,250
Energy per blow @ 90 psi 119.32 Joule 248.36 Joul e
Average air consumption 70 CFM 77 CFM
Air Inlet 3/4 in. NPT 3/4 in. NPT
Air hose minimum inside diameter 3/4 in. 3/4 in.
Required air pressure 90 psi (6.2 bar) 90 psi (6.2 bar)
Vibration value 15.6 m/s2 17.3 m/s2
Noise level 1 108 dB(A) 110 dB(A)
Overall length 36.5 in. (927mm) 29.6 in. (751.8mm)
Housing material steel steel
Oil reservoir capacity 18 cc 36 cc

Net weight 66 lb. (30 kg) 92.4 lb. (42 kg)
Shipping weight 70 lb. (31.8 kg) 98 lb. (44.5 kg)

1

The specified values are emission levels and are not necessarily to be seen as safe operating levels. As
workplace conditions vary, this information is intended to allow the user to make a better estimation of the
hazards and risks involved only.

Specifications were current at time of publication, but because of our policy of continuous improvement, JET
reserves the right to change specifications at any time and without prior notice, without incurring obligations.

JET

5

Setup and Assembly

Any missing parts or damage should be reported
immediately to your JET
damaged tool. Read this instruction manual
thoroughly for operation, maintenance and s afety
instructions.

Box contents:

1 Paving Breaker
1 Operation and parts manual
1 Warranty card

®

distributor. Do not use a

Operation

The paving breaker must be

properly lubricated before operation.

2. Remove oil plug and fill reservoir with air tool
oil up to lowest thread of fill hole. NOTE: Air
tool oil not provided; it is available at most
major hardware and tool stores. SAE #10 oil
may be used as a substitute. Do not use
detergent oil.

3. Reinstall plug. The oil control plug (#4, page
14; #3 page 16) can be turned to regulate
flow through the tool.

4. Remove protective cap from air inlet. Blow
out air line to remove any dirt or moisture,
then connect air supply hose t o tool. Set air
pressure to 90 psi.

IMPORTANT: Connecting a quick-change
coupling directly to the tool is not
recommended, as vibration may cause the
connection to fail. Instead, add a leader hose
and install any quick-change couplings
farther down the line.

5. Use both hands on grips, and place steel in
contact with work surface.

Figure 1 (JCT-4661 shown)

1. Pull down on retainer (Figure 1) to insert
steel (not provided). Apply greas e to shank
of steel before insertion. Push up on retainer
to secure steel, then tug on steel to ensure it
is properly caught in the bushing.

Note: When installing a chisel, blade should
be parallel with handles on breaker.

6. Push stop lever inward to release throttle
lever. Press and hold throttle lever. Rel ease
throttle lever to stop.

Apply constant pressure to work surface to
prevent as much recoil as possible. Release
throttle lever after breaking through the work, and
when removing tool from the work.

Important: Do NOT raise air pressure above
maximum rating for this paving breaker. If tool is
not accomplishing task at maximum air pressure
and flow, use a larger tool or different means to
achieve task.

When finished operating this tool, turn off air
supply and bleed residual air by pressing throttle
lever briefly. Disconnect air hose.

User-maintenance

Inspect paving breaker before each use. Ensure
that steel is secured inside retainer. After use,
wipe down the tool with a rag. Periodically apply
light coat of oil to exposed metal surfaces to inhibit
rust.

Periodically check torque of bolts in front and back
head. Loose bolts can result in loss of power and
tool damage. See “Torque specifications.”

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JCT-4660 series Paving Breaker