Central Pneumatic 67708 Installation manual

2-1/2 HP 10 GALLON
125 PSI AIR COMPRESSOR
Model 67708
SET UP AND OPERATING INSTRUCTIONS
Visit our website at: http://www.harborfreight.com
Read this material before using this product.
Failure to do so can result in serious injury.
SAVE THIS MANUAL.
Copyright©2010 by Harbor Freight Tools®. All rights reserved. No portion of this manual or any artwork
contained herein may be reproduced in any shape or form without the express written consent of
Harbor Freight Tools. Diagrams within this manual may not be drawn proportionally. Due to continuing
improvements, actual product may differ slightly from the product described herein. Tools required for
assembly and service may not be included.
For technical questions or replacement parts, please call 1-800-444-3353.
Manual Revised 11b

Page 2 For technical questions, please call 1-800-444-3353. SKU 67708
CONTENTS
IMPORTANT SAFETY
INFORMATION .................................3
GENERAL COMPRESSOR SAFETY
WARNINGS........................................... 3
AIR COMPRESSOR SAFETY
WARNINGS........................................... 4
GROUNDING ......................................6
110-120 V~ GROUNDED
COMPRESSORS: COMPRESSORS
WITH THREE PRONG PLUGS ............ 6
SYMBOLOGY.......................................... 7
SPECIFICATIONS...............................8
UNPACKING .......................................8
INSTRUCTIONS FOR PUTTING
INTO USE .........................................8
FUNCTIONS ............................................ 8
ASSEMBLY/MOUNTING......................... 9
CHECKING THE OIL............................. 10
GENERAL OPERATING
INSTRUCTIONS .............................11
COMPRESSOR AREA SET UP .............11
GENERAL OPERATION ........................11
EMERGENCY DEPRESSURIZATION .. 12
AUTOMATIC SHUT OFF SYSTEM ....... 12
MAINTENANCE AND SERVICING...13
CLEANING, MAINTENANCE, AND
LUBRICATION.................................... 13
MAINTENANCE SCHEDULE................ 13
OIL MAINTENANCE.............................. 14
DRAINING MOISTURE FROM THE
TANK................................................... 14
AIR FILTER MAINTENANCE ................ 14
TROUBLESHOOTING........................... 15
PARTS LIST......................................18
ASSEMBLY DIAGRAM.....................19
LIMITED 1 YEAR / 90 DAY
WARRANTY ...................................20

Page 3For technical questions, please call 1-800-444-3353.SKU 67708
SAVE THIS MANUAL
Keep this manual for the safety warnings
and precautions, assembly, operating,
inspection, maintenance and cleaning
procedures. Write the product’s serial number
in the back of the manual near the assembly
diagram (or month and year of purchase if
product has no number). Keep this manual
and the receipt in a safe and dry place for
future reference.
IMPORTANT SAFETY
INFORMATION
In this manual, on the labeling, and
all other information provided with
this product:
This is the safety alert
symbol. It is used to alert
you to potential personal
injury hazards. Obey all
safety messages that follow
this symbol to avoid possible
injury or death.
DANGER indicates a
hazardous situation
which, if not avoided, will result
in death or serious injury.
WARNING indicates a
hazardous situation
which, if not avoided, could
result in death or serious injury.
CAUTION, used with
the safety alert
symbol, indicates a hazardous
situation which, if not avoided,
could result in minor or moderate
injury.
NOTICE is used to
address practices not
related to personal injury.
CAUTION, without the
safety alert symbol, is
used to address practices not
related to personal injury.
General Compressor Safety
Warnings
WARNING Read all safety warnings
and instructions. Failure to follow
the warnings and instructions may
result in electric shock, re and/or
serious injury.
Save all warnings and instructions
for future reference.
1. Work area safety
a. Keep work area clean and well lit.
Cluttered or dark areas invite accidents.
b. Do not operate the Compressor in
explosive atmospheres, such as in
the presence of ammable liquids,
gases or dust. Compressor motors
produce sparks which may ignite the
dust or fumes.
c. Keep children and bystanders away
from an operating compressor.
2. Electrical safety
a. Compressor plugs must match the
outlet. Never modify the plug in
any way. Do not use any adapter
plugs with grounded compressors.
Standard plugs and matching outlets
will reduce risk of electric shock.
b. Do not expose compressor to rain
or wet conditions. Water entering
a compressor will increase the risk of
electric shock.
c. Do not abuse the cord. Never
use the cord for unplugging the

Page 4 For technical questions, please call 1-800-444-3353. SKU 67708
compressor. Keep cord away from
heat, oil, sharp edges or moving
parts. Damaged or entangled cords
increase the risk of electric shock.
3. Personal safety
a. Stay alert, watch what you are
doing and use common sense when
operating this compressor. Do
not use this compressor while you
are tired or under the inuence of
drugs, alcohol or medication. A
moment of inattention while operating
a compressor may result in serious
personal injury.
b. Use personal protective equipment.
Always wear ANSI-approved eye
protection during setup and use.
c. Prevent unintentional starting.
Ensure the switch is in the off-
position before connecting to power
source or moving the compressor.
4. Compressor use and care
a. Do not use the compressor if the
switch does not turn it on and
off. Any compressor that cannot be
controlled with the switch is dangerous
and must be repaired.
b. Disconnect the plug from the
power source before making any
adjustments, changing accessories,
or storing the compressor. Such
preventive safety measures reduce
the risk of starting the compressor
accidentally.
c. Store an idle compressor out of
the reach of children and do not
allow persons unfamiliar with the
compressor or these instructions to
operate it. A compressor is dangerous
in the hands of untrained users.
d. Maintain the compressor. Keep
the compressor clean for better
and safer performance. Follow
instructions for lubricating and
changing accessories. Keep dry,
clean and free from oil and grease.
Check for misalignment or binding
of moving parts, breakage of parts
and any other condition that may
affect the compressor’s operation.
If damaged, have the compressor
repaired before use. Many accidents
are caused by a poorly maintained
compressor.
e. Use the compressor in accordance
with these instructions, taking into
account the working conditions and
the work to be performed. Use of
the compressor for operations different
from those intended could result in a
hazardous situation.
5. Service
a. Have your compressor serviced by
a qualied repair person using only
identical replacement parts. This will
ensure that the safety of the compressor
is maintained.
Air Compressor Safety Warnings
1. Risk of re or explosion - do not
spray ammable liquid in a conned
area or towards a hot surface. Spray
area must be well-ventilated. Do not
smoke while spraying or spray where
spark or ame is present. Arcing
parts - keep compressor at least 20
feet away from explosive vapors,
such as when spraying with a spray
gun.
2. Risk of bursting - do not adjust
regulator higher than marked
maximum pressure of attachment.
3. Risk of injury - do not direct air
stream at people or animals.
4. Do not use to supply breathing air.

Page 5For technical questions, please call 1-800-444-3353.SKU 67708
5. Do not leave compressor unattended
for an extended period while plugged
in. Unplug compressor after working.
6. Keep compressor well-ventilated. Do
not cover compressor during use.
7. Drain Tank daily and after use. Internal
rust causes tank failure and explosion.
8. Add correct amount of compressor
oil before rst use and every use.
Operating with low or no oil causes
permanent damage and voids warranty.
9. Do not remove the valve cover or adjust
internal components.
10. Compressor head gets hot during
operation. Do not touch it or allow
children nearby during or immediately
following operation.
11. Do not use the air hose to move the
compressor.
12. Release the pressure in the storage tank
before moving.
13. The use of accessories or attachments
not recommended by the manufacturer
may result in a risk of injury to persons.
14. All air line components, including hoses,
pipe, connectors, lters, etc., must be
rated for a minimum working pressure
of 150 PSI, or 150% of the maximum
system pressure, whichever is greater.
15. USE OF AN EXTENSION CORD IS NOT
RECOMMENDED. If you choose to
use an extension cord, use the following
guidelines:
RECOMMENDED MINIMUM WIRE
GAUGE FOR EXTENSION CORDS
(120 VOLT)
NAMEPLATE
AMPERES
(at full load)
EXTENSION CORD
LENGTH
25’ 50’ 100’ 150’
0 – 6 18 16 16 14
6.1 – 10 18 16 Do not use.
10.1 – 12 16 16 Do not use.
12.1 – 16 14 12 Do not use.
TABLE A
a. Make sure your extension cord is in
good condition.
b. Be sure to use an extension cord
which is heavy enough to carry the
current your product will draw. An
undersized cord will cause a drop in line
voltage resulting in loss of power and
overheating. Table A shows the correct
size to use depending on cord length
and nameplate ampere rating. If in
doubt, use the next heavier gauge. The
smaller the gauge number, the heavier
the cord.
16. Industrial applications must follow OSHA
guidelines.
17. Maintain labels and nameplates on the
compressor. These carry important
safety information. If unreadable or
missing, contact Harbor Freight Tools for
a replacement.
18. This product is not a toy. Keep it out of
reach of children.
19. Operate unit on level surface. Check
oil level daily and ll to marked level if
needed.

Page 6 For technical questions, please call 1-800-444-3353. SKU 67708
20. People with pacemakers should
consult their physician(s) before use.
Electromagnetic elds in close proximity
to heart pacemaker could cause
pacemaker interference or pacemaker
failure.
21. WARNING: The brass components of
this product contain lead, a chemical
known to the State of California to cause
birth defects (or other reproductive
harm). (California Health & Safety code
§ 25249.5, et seq.)
22. The warnings, precautions, and
instructions discussed in this instruction
manual cannot cover all possible
conditions and situations that may occur.
It must be understood by the operator
that common sense and caution are
factors which cannot be built into this
product, but must be supplied by the
operator.
SAVE THESE
INSTRUCTIONS.
GROUNDING
TO PREVENT
ELECTRIC SHOCK
AND DEATH FROM INCORRECT
GROUNDING WIRE
CONNECTION:
Check with a qualied electrician
if you are in doubt as to whether
the outlet is properly grounded.
Do not modify the power cord
plug provided with the
compressor. Never remove the
grounding prong from the plug.
Do not use the compressor if the
power cord or plug is damaged.
If damaged, have it repaired by a
service facility before use. If the
plug will not t the outlet, have a
proper outlet installed by a
qualied electrician.
110-120 V~ Grounded Compressors:
Compressors with
Three Prong Plugs
1. In the event of a malfunction or
breakdown, grounding provides a path
of least resistance for electric current to
reduce the risk of electric shock. This
compressor is equipped with an electric
cord having an equipment-grounding
conductor and a grounding plug. The
plug must be plugged into a matching
outlet that is properly installed and
grounded in accordance with all local
codes and ordinances.
2. Do not modify the plug provided – if it will
not t the outlet, have the proper outlet
installed by a qualied electrician.
3. Improper connection of the equipment-
grounding conductor can result in a risk
of electric shock. The conductor with
insulation having an outer surface that
is green with or without yellow stripes is
the equipment-grounding conductor. If
repair or replacement of the electric cord
or plug is necessary, do not connect the
equipment-grounding conductor to a live
terminal.
4. Check with a qualied electrician or
service personnel if the grounding
instructions are not completely
understood, or if in doubt as to whether
the compressor is properly grounded.
5. Use only 3-wire extension cords that
have 3-prong grounding plugs and
3-pole receptacles that accept the
compressor’s plug.
6. Repair or replace damaged or worn cord
immediately.

Page 7For technical questions, please call 1-800-444-3353.SKU 67708
125 V~ 3-Prong Plug and Outlet
(for up to 125 V~ and up to 15 A)
Grounding
Pin
7. This compressor is intended for use on
a circuit that has an outlet that looks
like the one illustrated above in 125
V~ 3-Prong Plug and Outlet. The
compressor has a grounding plug that
looks like the plug illustrated above in
125 V~ 3-Prong Plug and Outlet.
8. The outlet must be properly installed and
grounded in accordance with all codes
and ordinances.
9. Do not use an adapter to connect this
compressor to a different outlet.
Symbology
PSI Pounds per square inch of
pressure
CFM Cubic Feet per Minute ow
SCFM Cubic Feet per Minute ow at
standard conditions
NPT National pipe thread, tapered
NPS National pipe thread, straight
Double Insulated
Canadian Standards Association
Underwriters Laboratories, Inc.
V~ Volts Alternating Current
AAmperes

Page 8 For technical questions, please call 1-800-444-3353. SKU 67708
SPECIFICATIONS
Electrical
Requirements 120 V~ / 60 Hz / 2.5 HP
Amperage 14A (Dedicated circuit
recommended)
Air Outlet Size 1/4” -18 NPT
Air Pressure Auto Shut-Off @ 125 PSI
Restart @ 95 PSI
Air Tank Capacity 10 Gallons
Air Flow Capacity 5.3 SCFM @ 90 PSI
6.2 SCFM @ 40 PSI
Oil Capacity 5.6 oz.
Oil Type
Air Compressor Oil
(Sold separately)
(SKU 95048)
Sound Level 89 dB @ 1m
UNPACKING
When unpacking, make sure that the
item is intact and undamaged. If any parts
are missing or broken, please call Harbor
Freight Tools at 1-800-444-3353 as soon as
possible.
INSTRUCTIONS FOR PUTTING
INTO USE
Read the ENTIRE IMPORTANT
SAFETY INFORMATION
section at the beginning of this
manual including all text under
subheadings therein before set up
or use of this product.
TO PREVENT
SERIOUS INJURY
FROM ACCIDENTAL
OPERATION:
Turn the Power Switch “OFF”
and unplug the Air Compressor
from its electrical outlet before
assembling or making any
adjustments to the compressor.
Note: For additional information regarding the
parts listed in the following pages, refer
to the Assembly Diagram near the end of
this manual.
Functions
Figure 1
ON/OFF
Power
Lever
(On
Pressure
Switch (54))
Oil Sight
Glass
(33)
Pressure
Regulator
(74)
Safety
Valve (73)
Tank Pressure
Gauge (53)
Output
Pressure
Gauge
(77)
Coupler
for
attaching
in-line
shutoff
valve, air
hose and
tool
Drain Valve (66)
OFF
ON
ON/OFF
Power
Lever
Tank Pressure
Gauge (53)
Output
Pressure
Gauge
(77)
Pressure
Regulator
(74)
Pressure
Switch
(54)
(Top View)
REV 11b

Page 9For technical questions, please call 1-800-444-3353.SKU 67708
Assembly/Mounting
1.
Figure 2
Bolt (64)
Bolt (64)
Hex
Nuts
(65)
Handle (72)
Bolts (71)
Bolts (71)
Tank (70)
Wheel (63)
Wheel (63)
Attach the Wheels to the Tank, using the
Bolts and Hex Nuts.
2. Slide the Handle into the two slots on the
top of the Tank and secure in place with
four Bolts.
3.
Figure 3
Air Filter
(6)
Cylinder Head (7)
Thread the Air Filter onto the side of the
Cylinder Head.
4. Break in the new Air Compressor as
follows:
a. Make sure the Power Switch is OFF
and the unit is unplugged. Insert a
male coupler (sold separately) into the
female Quick Coupler and fully open all
regulators and valves.
b. Plug in the Power Cord.
c. Turn the Power Switch ON.
d. Let the unit run for 30 minutes. Air will
expel freely through the Coupler.
e. Turn the Power Switch OFF.
f. Unplug the Power Cord and remove the
male coupler.
5. Connect a regulator valve, an inline shut
off valve and a 1/4” NPT air hose to the
Quick Coupler (all sold separately). The
air hose must be long enough to reach
the work area with enough extra length
to allow free movement while working.
Note: An in-line shutoff ball valve is an
important safety device because it
controls the air supply even if the air
hose is ruptured. The shutoff valve
should be a ball valve because it can
be closed quickly.
6.
Quick
Coupler
Sample Air Line Setup
Regulator with
Pressure Gauge
Quick
Coupler Air Hose
on Reel
Shut
Off
Valve FilterOiler
Coupler
Plug
Tool
Air
Compressor
Coupler
Plug
Depending on the tool which you will
be using with this compressor, you
may need to incorporate additional
components, such as an in-line oiler,
a lter, or a dryer (all sold separately).

Page 10 For technical questions, please call 1-800-444-3353. SKU 67708
Consult your air tool’s manual for needed
accessories.
Checking the Oil
1. Check the oil level before operation.
Fill the Pump Crankcase with premium
quality SAE 30-weight, non-detergent, air
compressor oil (sold separately).
IMPORTANT: Running the Air Compressor
with the incorrect amount of oil will
cause damage to the equipment
and void the warranty. To prevent
damage, do not use with overlled
or low oil. Slowly ll to full line, wait
2 minutes and ll back up to full line.
Compressor has small passages that
will ll slowly.
2.
Oil Sight Glass (33)
Crankcase Cover (31)
Tank (70)
OVERFILL
LOW
FULL
OIL LEVEL
Figure 5
The oil level should be at the center of
the “full” level on the oil level sight glass,
as shown in Figure 2. Add oil as needed
to maintain this level. Do not let the
oil level go below the center dot (LOW
as shown above) and do not overll
the oil so that it is above the center dot
(OVERFILL as shown above) on the
sight glass.
3. To add oil:
a. Remove the Oil Plug.
b. Using a funnel to avoid spills, pour
enough oil into the Pump Crankcase
to reach the “full” level in the Oil Sight
Glass.
c. Replace the Oil Plug.
Cold Weather Operation
Premium quality SAE 30-weight, non-
detergent, air compressor oil (sold
separately) is recommended for use
with this compressor. Start compressor
in heated area if outdoor temperatures
drop below 32° F. If this is not practical,
drain out the old pump oil and use SAE
10W Non-detergent Air Compressor Oil
in the pump crankcase instead whenever
the compressor’s temperature will fall
below 40°. Do not use multi-viscosity
oil (such as 10W-30), they leave carbon
deposits on pump components and lead
to accelerated failure. Heavy operation
may require heavier viscosity oil.
4. If uncertain which oil to use for this
compressor, please call Harbor Freight
Tools customer service at 1-800-444-
3353 for assistance.
5. Change the compressor oil after the
rst hour of use to remove any debris.
WARNING! To prevent serious injury from
burns: Do not add or change the oil while
the compressor is in operation. Allow the
compressor to cool before replacing oil.
REV 10e

Page 11For technical questions, please call 1-800-444-3353.SKU 67708
GENERAL OPERATING
INSTRUCTIONS
Read the ENTIRE IMPORTANT
SAFETY INFORMATION
section at the beginning of this
manual including all text under
subheadings therein before set up
or use of this product.
Compressor Area Set Up
1. Designate a work area that is clean and
well-lit. The work area must not allow
access by children or pets to prevent
injury.
2. Locate the Compressor on a at
level surface to ensure proper pump
lubrication and to prevent damage to the
unit. Keep at least 12” of space around
the unit to allow air circulation.
3. Route the power cord from the
compressor to the grounded wall outlet,
along a safe path without creating a
tripping hazard or exposing the power
cord to possible damage.
General Operation
1. Close the Drain Valve (66).
2. Make sure all nuts and bolts are tight.
3. Check for oil leaks and check the oil
level (See Checking the Oil).
4. Close the in-line Shutoff Valve between
the compressor and the air hose.
5. Make sure the air tool’s throttle or switch
in the off position.
6. Connect the air tool to the air hose.
7. Plug the Air Compressor Power Cord
into a grounded 120 V electrical outlet.
8. Open the in-line Shutoff Valve.
9. Turn the Power Switch ON.
10. Allow the Air Compressor to build up
pressure until it cycles off.
Note: At the beginning of the day’s rst use of
the Air Compressor, check for air leaks
by applying soapy water to connections
while the Air Compressor is pumping
and after pressure cut-out. Look for air
bubbles. If air bubbles are present at
connections, tighten connections. Do
not use the air compressor unless all
connections are air tight, the extra air
leaking out will cause the compressor to
operate too often, increasing wear on the
compressor.
Note: As long as the Power Switch is ON,
the operation of the Air Compressor
is automatic, controlled by an internal
pressure switch. The Compressor
will turn on automatically when the air
pressure drops to 95 PSI as indicated
on the Tank Pressure Gauge (53), and
will turn off automatically when the air
pressure reaches 125 PSI as indicated.
IMPORTANT: The internal pressure
switch is not user adjustable, do not
make changes to the air pressure
settings of the internal pressure
switch. Any change to the automatic
pressure levels may cause excess
pressure to accumulate, causing a
hazardous situation.
11. Adjust the Air Compressor’s Pressure
Regulator (74) so that the air output is
enough to properly power the tool, but
the output will not exceed the tool’s
maximum air pressure at any time.
Turn the knob clockwise to increase
the pressure and counter-clockwise to
decrease pressure. Adjust the pressure
gradually, while checking the air output
gauge to set the pressure.
12. Use the air tool as needed.

Page 12 For technical questions, please call 1-800-444-3353. SKU 67708
13. After the job is complete, turn the Power
Switch OFF.
14. Unplug the Air Compressor.
15. Close the in-line Shutoff Valve.
16. Bleed air from the tool then disconnect
the tool.
17. Turn the Drain Valve (66), at the bottom
of the Tank, two turns clockwise to
release any built-up moisture and the
internal tank pressure. Close the valve
after moisture has drained out. Do not
remove the Drain Valve.
18. Clean, then store the Air Compressor
indoors.
Emergency Depressurization
If it is necessary to quickly depressurize
the Compressor, turn the Power Switch
OFF. Then, pull on the ring on the Safety
Valve (73) to quickly release stored air
pressure.
Automatic Shut off System
1.
Reset Button
Figure 4
If the Compressor automatically shuts
off:
a. Shut off all tools.
b. Wait until the Compressor cools down
(about 10 minutes);
c. If the unit does not start up again on it’s
own, press the Reset Button to start the
compressor;
d. Resume operation.
2. Possible causes of repeated automatic
shut off of the compressor are:
a. Using an extension cord that is too long
or narrow;
b. An air leak or open hose causing the
compressor to cycle too often and build
up heat.
3. Correct any issues before further use to
avoid damage to the compressor.

Page 13For technical questions, please call 1-800-444-3353.SKU 67708
MAINTENANCE AND
SERVICING
Procedures not specically
explained in this manual must
be performed only by a qualied
technician.
TO PREVENT
SERIOUS INJURY
FROM ACCIDENTAL
OPERATION:
Turn the Power Switch “OFF”
and unplug the Compressor from
its electrical outlet before
performing any inspection,
maintenance, or cleaning
procedures.
TO PREVENT SERIOUS INJURY
FROM COMPRESSOR FAILURE:
Do not use damaged equipment.
If abnormal noise or vibration
occurs, have the problem
corrected before further use.
Cleaning, Maintenance, and
Lubrication
1. BEFORE EACH USE, inspect the
general condition of the Air Compressor.
Check for loose hardware, misalignment
or binding of moving parts, damaged
belts, cracked or broken parts, damaged
electrical wiring, and any other condition
that may affect its safe operation.
2. AFTER USE, wipe external surfaces of
the compressor with a clean cloth.
3. WARNING! If the supply cord
of this compressor is damaged, it
must be replaced only by a qualied
service technician.
Maintenance Schedule
Following are general guidelines
for maintenance checks of the Air
Compressor.
Note: The environment in which the
compressor is used, and the frequency
of use can affect how often you will need
to check the Air Compressor components
and perform maintenance procedures.
Daily:
a. Check oil level.
b. Check for oil leaks.
c. Make sure all nuts and bolts are tight.
d. Drain moisture from air tank.
e. Check for abnormal noise or vibration.
f. Check for air leaks.*
g. Wipe off any oil or dirt from the
compressor.**
Weekly:
a. Inspect Air Filter (6).
b. Inspect Oil Breather Plug (37).
Monthly:
Inspect Safety Valve (73).
Every 6 months or 100 Operation Hours:
Replace Pump oil.***
* To check for air leaks, apply soapy water to
joints while the Air Compressor is pressurized.
Look for air bubbles.
** To clean the compressor surface, wipe with
a damp cloth, using a mild detergent or mild
solvent.
*** Use Air Compressor Oil only (sold
separately - SKU 95048).

Page 14 For technical questions, please call 1-800-444-3353. SKU 67708
Oil Maintenance
Check the oil periodically for clarity.
Replace oil if it appears milky or if debris
is present, or every 6 months, or 100
hours of runtime, whichever comes rst.
In harsh environments such as high heat
or high humidity, you will need to replace
the oil more frequently.
WARNING: Risk of personal injury hazard.
Allow Air Compressor to cool before
changing the oil.
To drain the oil from the Pump Crankcase
(39):
a. Place a container under the Drain Plug
(35).
b. Remove the Oil Breather Plug (37) to
allow air ow into the Pump.
c. Remove the Drain Plug, allowing the oil
to drain into the container.
d. When the oil is completely drained from
the Pump, replace the Drain Plug.
e. Fill the Pump with new compressor oil
to the FULL level on the Oil Sight Glass.
f. Replace and tighten the Oil Breather
Plug.
g. Discard the old oil according to local,
state and federal regulations.
Draining Moisture from the Tank
The Drain Valve (66) is located under
the Tank (70). It must be accessed daily
to release all trapped air and moisture
from the Tank. This will eliminate
condensation which can cause tank
corrosion.
Note: Do not open the Drain Valve so that
more than four threads are showing.
To empty the air and condensation:
a. Make sure the Power switch of the
compressor is off.
b. Place a collection pan under the Drain
Valve.
c. Unthread the Drain Valve clockwise two
or three turns ONLY.
d. When all the pressure and moisture is
released, close the Drain Valve.
Air Filter Maintenance
Check the Air Filter weekly to see if it
needs replacement. If working in dirty
environments, you may need to replace
the lter more often. To replace the Air
Filter:
a. Unthread the Air Filter counterclockwise.
b. Replace with a new Air Filter.

Page 15For technical questions, please call 1-800-444-3353.SKU 67708
Troubleshooting
Problem Possible Causes Likely Solutions
Compressor does
not start or restart
1. Incorrect power supply.
2. No power at outlet.
3. Power cord not plugged in
properly.
4. Thermal overload switch
tripped.
5. Building power supply circuit
tripped or blown fuse.
6. Tank(s) already pressurized.
7. Cord wire size is too small or
cord is too long to properly
power compressor.
8. Compressor needs service.
1. Check that circuit matches compressor requirements.
2. Reset circuit breaker, or have outlet serviced by a qualied
technician.
3. Check that cord is plugged in securely.
4. Turn off Tool. Turn off Compressor and wait for it to cool down.
Press reset button. Resume operation.
5. Reset circuit or replace fuse. Check for low voltage conditions.
It may be necessary to disconnect other electrical appliances
from the circuit or move the compressor to its own circuit.
6. No problem. Compressor will start when needed.
7. Use larger diameter or shorter extension cord or eliminate
extension cord. See Recommended Wire Gauge for Extension
Cords in Safety section.
8. Have unit inspected by a qualied technician.
Compressor builds
pressure too slowly
1. Incorrect power supply.
2. Crankcase overlled with oil or
oil too thick.
3. Working environment too cold.
4. Safety valve needs service.
5. Loose ttings.
1. Check that circuit matches compressor requirements.
2. Drain oil and rell to proper level with recommended oil.
3. Move unit to a warmer location. Check that recommended oil
is in crankcase.
4. Listen for air leaking from valve. If leaking replace with
identical valve with same rating.
5. Reduce air pressure, then check all ttings with a soap solution
for air leaks and tighten as needed. Do not overtighten.
Compressor not
building enough air
pressure
1. Filters need cleaning/replacing.
2. Crankcase oil too thick.
3. Check Valve needs service.
4. Compressor not large enough
for job.
5. Loose ttings.
6. Hose or hose connections not
adequate.
7. High altitude reducing air
output.
1. Check inlet and outlet lters. Clean and/or replace as needed.
2. Drain oil and rell to proper level with recommended oil.
3. Have technician clean or replace, as needed.
4. Check if accessory SCFM is met by Compressor. If
Compressor cannot supply enough air ow (SCFM), you need
a larger Compressor.
5. Reduce air pressure, then check all ttings with a soap solution
for air leaks and tighten as needed. Do not overtighten.
6. Replace with larger hose and/or hose connections.
7. You may need a larger compressor if you are situated in a high
altitude location.
High Oil
Consumption
1. Crankcase oil too thin.
2. Unit not on level surface.
3. Crankcase vent clogged.
1. Drain oil and rell to proper level with recommended oil.
2. Reposition unit on a level surface.
3. Clean Crankcase vent.
Follow all safety precautions whenever diagnosing or servicing the
compressor. Disconnect power supply before service.

Page 16 For technical questions, please call 1-800-444-3353. SKU 67708
Problem Possible Causes Likely Solutions
Overheating 1. Filters need cleaning/replacing.
2. Crankcase oil too thin or
incorrect type.
3. Crankcase oil level too low.
4. Unusually dusty environment.
5. Cord is too small of a gauge or
too long to handle compressor.
6. Unit not on level surface.
1. Check inlet and outlet lters. Clean and/or replace as needed.
2. Drain oil and rell to proper level with recommended oil.
3. Add oil to proper level, check for leaks.
4. Clean and/or replace lters more often or move unit to cleaner
environment.
5. Increase cord size or use shorter length extension cord, or
eliminate extension cord. See Recommended Wire Gauge for
Extension Cords in Safety section.
6. Reposition unit on a level surface.
Compressor
starts and stops
excessively
1. Compressor not large enough
for job.
2. Loose ttings.
1. Check if accessory SCFM is met by Compressor. If
Compressor doesn’t reach accessory SCFM, you need a larger
Compressor.
2. Reduce air pressure, then check all ttings with a soap solution
for air leaks and tighten as needed. Do not overtighten.
Excessive noise 1. Crankcase overlled with oil
or oil is incorrect thickness or
type.
2. Crankcase oil level too low.
3. Loose or damaged belt guard.
4. Loose ttings.
5. Unit not on level surface.
1. Drain oil and rell to proper level with recommended oil.
2. Add oil to proper level, check for leaks.
3. Replace belt guard.
4. Reduce air pressure, then check all ttings with a soap solution
for air leaks and tighten as needed. Do not overtighten.
5. Reposition unit on a level surface.
Moisture in
discharge air
Too much moisture in air. Install inline air lter/dryer, and/or relocate to less humid
environment.
Oil in discharge air 1. Crankcase oil too thin or
crankcase overlled with oil.
2. Crankcase vents clogged.
1. Drain oil and rell to proper level with recommended oil.
2. Clean Crankcase vents.
Safety Valve “pops” Safety valve needs service. Pull on test ring of safety valve. If it still pops, replace.
Air leaks from pump
or ttings
Loose ttings. Reduce air pressure, then check all ttings with a soap solution for
air leaks and tighten as needed. Do not overtighten.
Air leaks from tank Defective or rusted tank. Have tank replaced by a qualied technician.
Follow all safety precautions whenever diagnosing or servicing the
compressor. Disconnect power supply before service.

Page 17For technical questions, please call 1-800-444-3353.SKU 67708
PLEASE READ THE FOLLOWING CAREFULLY
THE MANUFACTURER AND/OR DISTRIBUTOR HAS PROVIDED THE PARTS LIST AND ASSEMBLY
DIAGRAM IN THIS MANUAL AS A REFERENCE TOOL ONLY. NEITHER THE MANUFACTURER OR
DISTRIBUTOR MAKES ANY REPRESENTATION OR WARRANTY OF ANY KIND TO THE BUYER THAT HE
OR SHE IS QUALIFIED TO MAKE ANY REPAIRS TO THE PRODUCT, OR THAT HE OR SHE IS QUALIFIED
TO REPLACE ANY PARTS OF THE PRODUCT. IN FACT, THE MANUFACTURER AND/OR DISTRIBUTOR
EXPRESSLY STATES THAT ALL REPAIRS AND PARTS REPLACEMENTS SHOULD BE UNDERTAKEN BY
CERTIFIED AND LICENSED TECHNICIANS, AND NOT BY THE BUYER. THE BUYER ASSUMES ALL RISK
AND LIABILITY ARISING OUT OF HIS OR HER REPAIRS TO THE ORIGINAL PRODUCT OR REPLACEMENT
PARTS THERETO, OR ARISING OUT OF HIS OR HER INSTALLATION OF REPLACEMENT PARTS THERETO.
Record Product’s Serial Number Here:
Note: If product has no serial number, record month and year of purchase instead.
Note: Some parts are listed and shown for illustration purposes only, and are not available
individually as replacement parts.

Page 18 For technical questions, please call 1-800-444-3353. SKU 67708
PARTS LIST
Part Description Qty
1 Cover 1
2 Elbow 1
3 Start Valve 1
4 Spring Washer M6 8
5 Screw M6 x 50 4
6 Air Filter 1
7 Cylinder Head 1
8 Head Gasket 1
9 Valve Plate 2
10 Metal Gasket 1
11 Valve 2
12 Valve Plate Gasket 1
13 Cylinder 1
14 Bolt M8 x 30 2
15 Spring Washer M8 3
16 Cylinder Gasket 1
17 Pin 1
18 Compression Ring 2
19 Oil Ring 1
20 Wrist Pin Retainer 2
21 Piston 1
22 Connecting Rod 1
23 Screw M6 x 20 5
24 Hex Nut M6 3
25 Crank Shaft 1
26 O-Ring 2
26a Zip Tie 1
27 Capacitor 1
28 Screw M8 x 20 1
29 Capacitor Bracket 1
30 Hex Nut M8 1
31 Crank Case Cover 1
32 O-Ring 1
33 Oil Sight Glass 1
34 O-Ring 1
35 Drain Plug M5 x 10 1
36 O-Ring 1
37 Oil Breather Plug 1
38 Crankcase Cover Gasket 1
39 Pump Crankcase 1
40 Washer M5 10
41 Screw M5 x 16 10
Part Description Qty
42 Manual Overload Protector 1
43 Oil Seal 1
44 Bearing 1
45 Rotator 1
46 Bearing 1
47 Stator 1
48 Automatic Thermal Protector 1
49 End Cover 1
50 Fan 1
51 Circlip 1
51a Plain Washer 5 4
51b Spring Washer 5 4
51c Bolt 4
52 Connector 1
53 Tank Pressure Gauge 1
54 Pressure Switch 1
55 Unloader Tube 1
56 Nut 1
57 Ferrule 1
58 Check Valve 1
59 Ferrule 2
60 Nut 2
61 Exhaust Tube 1
62 Cooling Fin 1
63 Wheel 2
64 Bolt M12 x 55 (washer/bushing
assembly)
2
65 Hex Nut M12 2
66 Drain Valve 1
67 Foot Pad 2
68 Washer 2
69 Screw M6 x 25 2
70 Tank 1
71 Bolt M6 x 10 4
72 Handle 1
73 Safety Valve 1
74 Pressure Regulator 1
75 Motor Cord 1
76 Quick Coupler 1
77 Output Pressure Gauge 1
78 Plug 1

Page 19For technical questions, please call 1-800-444-3353.SKU 67708
ASSEMBLY DIAGRAM

Page 20 For technical questions, please call 1-800-444-3353. SKU 67708
LIMITED 1 YEAR / 90 DAY
WARRANTY
Harbor Freight Tools Co. makes every
effort to assure that its products meet
high quality and durability standards, and
warrants to the original purchaser that for
a period of one year from date of purchase
that the tank is free of defects in materials
and workmanship (90 days if used by a
professional contractor or if used as rental
equipment). Harbor Freight Tools also
warrants to the original purchaser, for a
period of ninety days from date of purchase,
that all other parts and components of the
product are free from defects in materials and
workmanship. This warranty does not apply
to damage due directly or indirectly to misuse,
abuse, negligence or accidents, repairs or
alterations outside our facilities, normal wear
and tear, or to lack of maintenance. We
shall in no event be liable for death, injuries
to persons or property, or for incidental,
contingent, special or consequential damages
arising from the use of our product. Some
states do not allow the exclusion or limitation
of incidental or consequential damages,
so the above limitation of exclusion may
not apply to you. THIS WARRANTY IS
EXPRESSLY IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING THE WARRANTIES OF
MERCHANTABILITY AND FITNESS.
To take advantage of this warranty,
the product or part must be returned to us
with transportation charges prepaid. Proof
of purchase date and an explanation of the
complaint must accompany the merchandise.
If our inspection veries the defect, we
will either repair or replace the product at
our election or we may elect to refund the
purchase price if we cannot readily and
quickly provide you with a replacement. We
will return repaired products at our expense,
but if we determine there is no defect, or that
the defect resulted from causes not within the
scope of our warranty, then you must bear the
cost of returning the product.
This warranty gives you specic legal
rights and you may also have other rights
which vary from state to state.
3491 Mission Oaks Blvd. • PO Box 6009
Camarillo, CA 93011 • [phone]