Matco Tools MT1761 Instruction Manual

• Operating Instructions • Warning Information

• Parts Breakdown

S P E C I F I C A T I O N S

MT1761

Maximum Free Speed . . . . . . . . . . . . . . . . . . . . . . . 7,700 RPM

Working Torque. . . . . . . . . . . . . . . . . . . . . . . . . 50-420 FT. LBS.

Maximum Torque . . . . . . . . . . . . . . . . . . . . . . . . . . 510 FT. LBS.

Air Inlet Thread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1/4" NPT

Air Hose Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3/8" ID

Average Air Consumption. . . . . . . . . . . . . . . . . . . . . . . 4.6 CFM

Recommended Air Pressure . . . . . . . . . . . . . . . 90 PSIG (6.2 BAR)

Sound Level. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97.3 dBA

Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.48"

Net Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.11 LBS.

MT1761

1/2" Composite

Impact Wrench

ALWAYS READ
INSTRUCTIONS
BEFORE USING
POWER TOOLS

ALWAYS WEAR
SAFETY GOGGLES

WEAR HEARING
PROTECTION

AVOID
PROLONGED
EXPOSURE TO
VIBRATION

MT1761 1 Rev. 01/19/05

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

• lead from lead-based paints,

• crystalline silica from bricks and cement and other masonry products, and

• arsenic and chromium from chemically-treated lumber.

Your risk from these exposures 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 those dust masks that are specially
designed to filter out microscopic particles.

MT1761 1/2" Composite Impact Wrench

FAILURE TO OBSERVE THESE WARNINGS COULD RESULT IN INJURY

This Instruction Manual Contains Important
Safety Information.

Read THIS INSTRUCTION MANUAL Carefully
and understand ALL INFORMATION Before
Operating THIS Tool.

• Always operate, inspect and maintain this
tool in accordance with American National
Standards Institute Safety Code of Portable Air
Tools (ANSI B186.1) and any other applicable
safety codes and regulations.

• For safety, top performance and
maximum durability of parts, operate this tool
at 90 psig/6.2 bar max air pressure with 3/8”
diameter air supply hose.

• Always wear impact-resistant eye and face
protection when operating or performing
maintenance on this tool. Always wear hearing
protection when using this tool.

• High sound levels can cause permanent
hearing loss. Use hearing protection as
recommended by your employer or
OSHA regulation.

• Keep the tool in efficient operating condition.

• Operators and maintenance personnel must be
physically able to handle the bulk, weight and
power of this tool.

• Air under pressure can cause severe injury.
Never direct air at yourself or others. Always
turn off the air supply, drain hose of air
pressure and detach tool from air supply
before installing, removing or adjusting any
accessory on this tool, or before performing
any maintenance on this tool. Failure to do
so could result in injury. Whip hoses can cause
serious injury. Always check for damaged,
frayed or loose hoses and fittings, and
replace immediately. Do not use quick detach
couplings at tool. See instructions for
correct set-up.

• Air powered tools can vibrate in use. Vibration,
repetitive motions or uncomfortable positions
over extended periods of time may be harmful
to your hands and arms. Discontinue use of
tool if discomfort, tingling feeling or pain
occurs. Seek medical advice before
resuming use.

• Place the tool on the work before starting the
tool. Do not point or indulge in any horseplay
with this tool.

• Slipping, tripping and/or falling while
operating air tools can be a major cause of
serious injury or death. Be aware of excess
hose left on the walking or work surface.

• Keep body working stance balanced and firm.
Do not overreach when operating the tool.

• Anticipate and be alert for sudden changes in
motion during start up and operation of any
power tool.

• Do not carry tool by the hose. Protect the hose
from sharp objects and heat.

• Tool shaft may continue to rotate briefly after
throttle is released. Avoid direct contact with
accessories during and after use. Gloves will
reduce the risk of cuts or burns.

• Keep away from rotating end of tool. Do not
wear jewelry or loose clothing. Secure long
hair. Scalping can occur if hair is not kept away
from tool and accessories. Choking can occur if
neckwear is not kept away from tool
and accessories.

• Never use a chisel as a handstruck tool. They
are designed and heat treated to be used only
in air hammers. Select the correct shank and
retainer for the tool.

• Never use dull accessories. Never cool a hot
accessory in water as brittleness and early
failure can result. Accessory breakage or tool
damage may result from prying. Take smaller
bites to avoid getting stuck.

• Do not lubricate tools with flammable or
volatile liquids such as kerosene, diesel or
jet fuel.

• Do not force tool beyond its rated capacity.

• Do not remove any labels. Replace any
damaged labels.

• Use accessories recommended by Matco Tools.

OPERATION

The reversing valve can be used as an air throttle, if there are no
other means of regulating air. Turn the reversing valve all the way
to the right for maximum power.

The reversing valve can be used to adjust torque to the
approximate tightness of a known fastener.

To set the tool to desired torque, select a nut or screw of known
tightness of the same size, thread pitch and thread condition
as those on the job. Turn reversing valve to low position, apply
wrench to nut and gradually increase power (turn regulator to
admit more air) until nut moves slightly in the direction it was
originally set. The tool is now set to duplicate that tightness

- note regulator setting for future use. When tightening nuts not

MT1761 2 Rev. 01/19/05

requiring critical torque values, run nut up flush and then tighten
an additional one-quarter to one-half turn (slight additional
turning is necessary if gaskets are being clamped). For additional
power needed on disassembly work, turn regulator to its fully
open position. This impact wrench is rated at 1/2" USS bolt
size. Rating must be down graded for spring U bolts, tie bolts,
long cap screws, double depth nuts, badly rusted conditions and
spring fasteners as they absorb much of the impact power. When
possible, clamp or wedge the bolt to prevent springback.

Soak rusted nuts in penetrating oil and break rust seal before
removing with impact wrench. If nut does not start to move in
three to five seconds use a larger size impact wrench. Do not
use impact wrench beyond rated capacity as this will drastically
reduce tool life.

MT1761 1/2" Composite Impact Wrench

Nipple

FEATURES

• Powerful twin hammer impact mechanism for super power to
weight ratio.

• Only 4.11 lbs. of weight with maximum torque of 510 ft. lbs.

• Matco exclusive composite back housing with comfort grip and
super light magnesium front housing, produce a great feeling and
very durable tool.

• Rear housing forward reverse lever for easy one hand operation.

• Built in regulator system on forward reverse lever provides
unmatched versatility.

• Bottom handle exhaust to direct air away from the work.

AIR SUPPLY

Tools of this class operate on a wide range of air pressures. It is
recommended that air pressure of these tools measures 90 PSI
at the tool while running free. Higher pressure and unclean air
will shorten tool life because of faster wear and may create a
hazardous condition.

Water in the air line will cause damage to the tool. Drain the air
tank daily. Clean the air inlet filter screen on at least a weekly
schedule. The recommended hook-up procedure can be viewed
in Figure 1.

The air inlet (Figure 2), used for connecting air supply, has standard
1/4" NPT American Thread.

Line pressure should be increased to compensate for unusually
long air hoses (over 25 feet). Minimum hose diameter should be
3/8" I.D. and fittings should have the same inside dimensions.

FIG. 1

TROUBLESHOOTING

Other factors outside the tool may cause loss of power or erratic
action. Reduced compressor output, excessive drain on the air line,
moisture or restrictions in air pipes or the use of hose connections
of improper size or poor conditions may reduce air supply. If
outside conditions are in order and the tool still has erratic
performance, disconnect tool from hose and take tool to your
nearest Matco authorized service center.

LUBRICATION & MAINTENANCE

Lubricate the tool daily with a good grade of air tool oil. If no
air line oiler is used, run a teaspoon of oil through the tool. The oil
can be squirted into the tool air inlet Figure 2, or into the hose at
the nearest connection to the air supply, then run the tool. A rust
inhibitive oil is acceptable for air tools.

AIR INLET

FIG. 2

WARRANTY

Matco warrants its air tools for a period of 1 year to the consumer.
We will repair any MT Series air tool covered under this warranty
which proves to be defective in material or workmanship during the
warranty period. In order to have your tool repaired, return the tool
to either of the Matco Authorized Warranty Centers listed below,
freight prepaid. Please include a copy of your proof of purchase
and a brief description of the problem. The tool will be inspected
and if any part or parts are found to be defective in material or
workmanship, the tool will be repaired free of charge and returned
to you freight prepaid.

This warranty gives you specific rights. You may also have other
rights which vary from state to state.

The foregoing obligation is Matco’s sole liability under this or any
implied warranty and under no circumstances shall Matco be liable
for any incidental or consequential damages.

Note: Some states do not allow the exclusion or limitation of

MT1761 3 Rev. 01/19/05

incidental or consequential damages so the above limitation or
exclusion may not apply to you.

MATCO AIR COMMAND
Tool Repair SV
1330 Commerce Dr.
Stow, OH 44224
[phone]

DISCOUNT TOOL REPAIR
3433 Losee Rd. #1
North Las Vegas, NV 89030
[phone]

MT1761 1/2" Composite Impact Wrench

REF. NO. PART NO. DESCRIPTION QTY.

101 RS1761101 Hammer Case 1
102 RS1761102 Hammer Case Gasket 1
103 RS1761103 Hammer Case Bushing 1
104 RS1761104 Socket Retainer 1
105 RS1734410 O-Ring 1
106 RS1761106 Anvil 1
107 RS1761107 Hammer Frame Pin 2
108 RS1761108 Hammer 2
109 RS1761109 Hammer Frame 1
110 RS1761110 Hammer Case Grease Fitting 1
201 RS1761201A Housing (incl. #412, 413 and 414) 1
203 RS1761203 Rear Cover Gasket 1
204 RS1761204 Rear Cover 1
205 RS1761205 Star Head Bolt 4
301 RS221RA32 Bearing 1
302 RS1761302 Front End Plate 1
303 RS1761303 Cylinder 1
304 RS1761304 Rotor 1
305 RS1761305 Blades 6
306 RS1761306 Rear End Plate 1
307 RS227B25 Bearing 1
308 RS1761308 Rear End Plate Gasket 1

TUNE UP KIT

MT1761TK includes:
reference numbers 102, 104,
105, 203, 305 (6), 308, 313,
316 (4), 402, 403, 410 (2)
and 414

REF. NO. PART NO. DESCRIPTION QTY.

309 RS1761309 Regulator Base 1
310 RS1735312 Spring 1
311 RS1735313 Ball 1
312 RS1735314 Reverse Valve 1
313 RS1735316 O-Ring 1
314 RS1735319 Hex Socket Heavy Duty Bolt 3
315 RS1761315 Inlet 1
316 RS1761316 O-Ring 4
401 RS1735401 Insert Bushing 1
402 RS1735402 O-Ring 1
403 RS1735403 Seal 1
404 RS1735404 Bushing 1
405 RS1735405 Tip Valve 1
406 RS1735406 Spring 1
407 RS1735407 Muffler 1
408 RS1735408 Exhaust Deflector 1
409 RS1735411 Tap Bolt 1
410 RS1735410 O-Ring 2
411 RS1735409 Air Inlet 1
412 RS1735412 Spring Pin 1
413 RS400413 Trigger (8mm Pin) 1
414 RS400414 O-Ring 1

MT1761 4 Rev. 01/19/05