Sullair 300HH Installation and maintenance instructions

OPERATOR’S MANUAL AND PARTS LIST
Po r t a b l e ai r Co m P r e s s o r
300HH, 375, 375H a n d 425 ex P o r t
Caterpillar Standard and Aftercooled and Filtered
PART NUMBER:
02250169-733
©
SULLAIR CORPORATION
The information in this document
is correct at the time of printing for
portable compressor serial number
200705010000
and all subsequent serial numbers.
KEEP FOR
FUTURE
REFERENCE

AIR CARE SEMINAR TRAINING
Sullair Air Care Seminars are courses that provide hands-on instruction in the proper operation, maintenance
and service of Sullair equipment. Individual seminars on Portable compressors are presented at regular intervals
throughout the year at a dedicated training facility at Sullair’s corporate headquarters in Michigan City, Indiana.
Instruction includes discussion of the function and installation of Sullair service parts, troubleshooting of the
most common problems, and actual equipment operation. The seminars are recommended for Rental House,
Contractor Maintenance and Service Personnel.
For detailed course outlines, schedule and cost information contact:
Sullair Customer Care Training Department
: 1-888-SULLAIR or
219-879-5451 (ext. 5363)
www.sullair.com
- Or Write -
Sullair Corporation
3700 E. Michigan Blvd.
Michigan City, IN 46360
Attn: Service Training Department

iii
375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
TABLE OF CONTENTS
1 - SAFETY ........................................................................................................... 1
GENERAL....................................................................................................... 1
Towing............................................................................................................. 1
Preparing To Tow...................................................................................... 1
Towing ..................................................................................................... 3
Parking Or Locating Compressor ............................................................. 3
Pressure Release ........................................................................................... 4
Fire And Explosion .......................................................................................... 5
Moving Parts ................................................................................................... 6
Hot Surfaces, Sharp Edges And Sharp Corners............................................. 6
Toxic And Irritating Substances....................................................................... 6
Electrical Shock .............................................................................................. 7
Lifting .............................................................................................................. 7
Entrapment ..................................................................................................... 8
Jump Starting.................................................................................................. 8
California Proposition 65 .................................................................................. 9
Implementation of Lockout/Tagout .................................................................. 9
explosive atmosphere ................................................................................... 10
2 - DESCRIPTION............................................................................................... 11
Introduction .................................................................................................. 11
Description Of Components.......................................................................... 11
Sullair Compressor Unit, Functional Description .......................................... 13
Compressor Cooling And Lubrication System, Functional Description......... 13
Compressor Discharge System, Functional Description............................... 14
Capacity ContRol SysTem, Functional Description....................................... 14
Start – 0 To 40 psig (0 To 2.8 Bar) Cold Start......................................... 14
Normal Operation – 80 to 100 psig (5.6 to 6.9 bar) or 80 to 150 psig
(5.6 to 10.3 bar) for H machines or 80 to 200 psig (5.6 to 13.8 bar) for
HH machines .......................................................................................... 20
Modulation – 100 to 110 psig (6.9 to 7.5 bar) or 150 to 165 psig (10.3
to 11.4 bar) for H machines or 200 to 220 psig (13.8 to 15.2 bar) for
HH machines .......................................................................................... 20
Shutdown ............................................................................................... 20
Air Inlet System, Functional Description ...................................................... 20
Instrument Panel Group, Functional Description .......................................... 20
Wiring Diagram ............................................................................................. 22
Electrical System, Functional Description..................................................... 23
Compressor Shutdown & Warning System, Functional Description ............. 23

iv 375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
SECTION 7
Aftercooled And Filtered Air System, Functional Description........................ 24
3 - SPECIFICATIONS ......................................................................................... 25
Specications – 300HH and 375 Caterpillar ................................................. 25
Specications – 375H and 425 Caterpillar.................................................... 26
Lubrication Guide – Compressor .................................................................. 28
Application Guide.......................................................................................... 28
Lubrication Guide – Engine........................................................................... 28
4 - GENERAL...................................................................................................... 29
General ......................................................................................................... 29
Purpose Of Controls ..................................................................................... 29
Control or Indicator Purpose................................................................... 29
Initial Startup/Shutdown Procedure .............................................................. 30
Startup .................................................................................................... 30
Shutdown................................................................................................ 30
Restart Procedure......................................................................................... 30
5 - MAINTENANCE............................................................................................. 31
General ......................................................................................................... 31
Daily Maintenance ........................................................................................ 31
Maintenance After Initial 50 Hours Of Operation .......................................... 32
Maintenance Every 50 Hours........................................................................ 32
Maintenance Every 100 Hours...................................................................... 32
Maintenance Every 250 Hours...................................................................... 32
Maintenance Every 1500 Hours.................................................................... 32
Part Replacement And Adjustment Procedures............................................ 33
Compressor Fluid Change Procedure .................................................... 33
Compressor Fluid Filter Element Replacement...................................... 33
Air Filter Maintenance ............................................................................ 33
Air Filter Replacement ............................................................................ 33
Element Inspection ................................................................................. 34
Separator Element Replacement ........................................................... 34
Procedure For Setting Speed And Pressure Controls On Portable
Compressors Equipped With Poppet Valves ......................................... 34
Bearing Lubrication................................................................................. 36
First and Second Stage Discharge Air Filter Maintenance – Aftercooled &
Filtered Models ....................................................................................... 37
Trouble Shooting........................................................................................... 38
6 - NOISE CONTROL ......................................................................................... 43
Noise Emissions Warranty ............................................................................ 43
Tampering with the Noise Control System is Prohibited ............................... 43
Noise Emission Maintenance and Maintenance Record Log................. 44
Noise Emissions Maintenance and Maintenance Record Log...................... 44
Procedure For Ordering Parts....................................................................... 47
7 - ILLUSTRATIONS AND PARTS LIST ............................................................ 47
Recommended Spare Parts List ................................................................... 49
Engine, Compressor And Parts..................................................................... 50
Radiator & Compressor Fluid Cooling System ............................................. 54
Air Inlet System & Exhaust System .............................................................. 58
Control Parts & Discharge Parts - 375 and 425............................................ 60
Control Parts & Discharge Parts - 300HH and 375H .................................... 64
Regulator/Blowdown Valve - 375 And 425 .................................................... 68
Regulator/Blowdown Valve - 300HH and 375H ............................................ 70
Control Parts Orice - 300HH and 375H....................................................... 72
Service Valves............................................................................................... 74
Optional AfterCooler/Filter And Parts ............................................................ 76

v
375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
TABLE OF CONTENTS
Electrical Parts .............................................................................................. 80
Instrument Panel & Parts .............................................................................. 82
Fuel Tank & Connections .............................................................................. 86
Frame, Axle & Parts And Axle Assembly....................................................... 88
Axle Assembly............................................................................................... 92
Canopy, Acoustical Panels & Parts ............................................................... 94
Decals ........................................................................................................... 96
Decal Locations .......................................................................................... 108

vi 375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
SECTION 7
THIS PAGE INTENTIONALLY LEFT BLANK

1
Section 1
SAFETY
GENERAL1.1
Sullair Corporation designs and manufactures all of its
products so they can be operated safely. However, the
responsibility for safe operation rests with those who use
and maintain these products. The following safety
precautions are offered as a guide which, if
conscientiously followed, will minimize the possibility of
accidents throughout the useful life of this equipment.
Read the CIMA Safety Manual prior to compressor
operation and towing, if applicable in your area.
The air compressor should be operated only by those who
have been trained and delegated to do so, and who have
read and understood this Operator’s Manual. Failure to
follow the instructions, procedures and safety precautions
in this manual can result in accidents and injuries.
NEVER start the air compressor unless it is safe to do so.
DO NOT attempt to operate the air compressor with a
known unsafe condition. Tag the air compressor and
render it inoperative by disconnecting the battery so others
who may not know of the unsafe condition will not attempt
to operate it until the condition is corrected.
Use and operate the air compressor only in full compliance
with all pertinent OSHA requirements and/or all pertinent
Federal, State and Local codes or requirements.
DO NOT modify the compressor except with written
factory approval.
Each day, walk around the air compressor and inspect for
leaks, loose or missing parts, damaged parts or parts out
of adjustment. Perform all recommended daily
maintenance.
Inspect for torn, frayed, blistered or otherwise deteriorated
and degraded hoses. Replace as required.
TOWING1.2
Preparing To Tow
NOTE
OPERATOR IS REQUIRED TO READ
ENTIRE INSTRUCTION MANUAL.
CAUTION
Estimated hose life based on a 5-day
8-hour work week is 3 years. These
conditions exist on an 8-hour shift
only. Any other operation of the
equipment other than 8-hour shifts
would shorten the hose life based on
hours of operation.
WARNING
DO NOT tow the compressor should
its weight exceed the rated limit of the
tow vehicle, as the vehicle may not
brake safely with excess weight. See
rated limit in tow vehicle Operator’s
Manual, and review its instructions
and other requirements for safe
towing.
NOTE
While not towed in the usual sense of
the word, many of these instructions
are directly applicable to skid-
mounted portable air compressors as
well.

2
SECTION 1
Prior to hitching the air compressor to the tow vehicle,A.
inspect all attachment parts and equipment, checking
for (i) signs of excessive wear or corrosion, (ii) parts
that are cracked, bent, dented or otherwise deformed
or degraded, and (iii) loose nuts, bolts or other
fasteners. Should any such condition be present, DO
NOT TOW until the problem is corrected.
Back the tow vehicle to the compressor and positionB.
it in preparation for coupling the compressor.
If the compressor is provided with a drawbar latchedC.
in the vertical upright position, carefully unlatch
drawbar and lower it to engage the coupling device. If
not, raise drawbar to engage coupling device or
otherwise couple the compressor to the towing
vehicle.
Make sure the coupling device is fully engaged,D.
closed and locked.
If chains are provided, pass each chain through itsE.
point of attachment on the towing vehicle; then hook
each chain to itself by passing the grab hook over
(not through) a link. Cross chains under front of
drawbar before passing them through points of
attachment on towing vehicle to support front of
drawbar in case it should accidentally become
uncoupled.
Make sure that the coupling device and adjacentF.
structures on the towing vehicle (and also, if utilized,
chain adjustment, brake and/or electrical
interconnections) DO NOT interfere with or restrict
motion of any part of the compressor, including its
coupling device, with respect to the towing vehicle
when maneuvering over any anticipated terrain.
If provided, make sure chain length, brake andG.
electrical interconnections provide sufcient slack to
prevent strain when cornering and maneuvering, yet
are supported so they cannot drag or rub on road,
terrain or towing vehicle surfaces which might cause
wear that could render them inoperative.
On two-wheeled models, fully retract front screw jackH.
and any rear stabilizer legs. If a caster wheel is
provided on the screw jack it is part of the screw jack,
and can not be removed. Follow the same procedure
for stowing away the wheeled jack as you would for
the standard screw jack. Pull the pin connecting the
jack to the drawbar and raise the screw jack to its full
upright position. Rotate the screw jack to its stowed
position, parallel to the drawbar, and reinsert the pin.
Make sure the jack is secured in place prior to towing.
Make sure tires are in good condition and are theI.
size (load range) specied and are inated to the
specied pressures. DO NOT change the tire size or
type. Also, make sure wheel bolts, lugs or nuts are
tightened to the specied torques.
WARNING
This equipment may be tongue heavy.
DO NOT attempt to raise or lower the
drawbar by hand if the weight is more
than you can safely handle.
Use the screw jack provided or a
chain fall if you cannot lift or lower
it without avoiding injury to yourself
or others. Keep hands and ngers
clear of the coupling device and all
other pinch points. Keep feet clear
of drawbar to avoid injury in case it
should slip from your hands.
WARNING
This equipment may be tongue heavy.
DO NOT attempt to raise or lower the
drawbar by hand if the weight is more
than you can safely handle.
CAUTION
Retract the front screw jack only
after attaching the compressor to the
tow vehicle. Raise the screw jack to
its full up position and pull the pin
connecting the jack to the drawbar.
Rotate the screw jack to its stowed
position, parallel to the drawbar, and
reinsert the pin. Make sure the jack is
secured in place prior to towing.
If a caster wheel is provided on the
screw jack it is part of the screw jack
and can not be removed. Follow the
same procedure for stowing away
the wheeled jack as you would for
the standard screw jack. Pull the pin
connecting the jack to the drawbar
and raise the screw jack to its full
up position. Rotate the screw jack
to its stowed position, parallel to the
drawbar, and reinsert the pin. Make
sure the jack is secured in place prior
to towing.

3
SAFETY
If provided, make sure all dual stop, tail directionalJ.
and clearance lights are operating properly and that
their lenses are clean and functional. Also, make sure
all reectors and reecting surfaces, including the
slow moving vehicle emblem on compressors
provided with same, are clean and functional.
Make sure all service air hoses (not air brake hoses)K.
are disconnected or are fully stowed and secured on
hose reels, if provided.
Make sure all access doors and tool box covers areL.
closed and latched. If the compressor is large enough
to hold a man, make sure all personnel are out before
closing and latching access doors.
Make sure parking brakes in towing vehicle are set,M.
or that its wheels are chocked or blocked, or that it is
otherwise restrained from moving. Then, release the
compressor parking brakes, if provided.
Make sure the compressor wheels are not chockedN.
or blocked, and that all tie-downs, if any, are free.
Test running brake operation, including breakawayO.
switch operation if provided, before attempting to tow
the compressor at its rated speed or less when
conditions prevail.
DO NOTP. carry loose or inappropriate tools,
equipment or supplies on or in the compressor.
DO NOTQ. load this equipment with accessories or
tools such that it is unbalanced from side to side or
front to back. Such unbalance will reduce the
towability of this equipment and may increase the
possibility of tipping, rolling over, jackkning, etc.
Loss of control of the towing vehicle may result.
Towing
Observe all Federal, State, and Local laws whileA.
towing this equipment (including those specifying
minimum speed).
DO NOTB. exceed the towing speeds listed below
under ideal conditions. Reduce your speed according
to posted speed limits, weather, trafc, road or terrain
conditions:
Two axle four-wheel or three axle six-wheel1.
steerable models: 15 MPH (24 km/h).
All other models: 55 MPH (88 km/h).2.
Remember that the portable air compressor mayC.
approach or exceed the weight of the towing vehicle.
Maintain increased stopping distances accordingly.
DO NOT make sudden lane changes, U-turns or
other maneuvers. Such maneuvers can cause the
compressor to tip, roll over, jackknife or slide and
cause loss of control of the towing vehicle. Tipping,
rolling over, etc. can occur suddenly without warning.
U-turns especially should be made slowly and
carefully.
Avoid grades in excess of 15 (27%).D.
Avoid potholes, rocks and other obstructions, andE.
soft shoulders or unstable terrain.
Maneuver in a manner that will not exceed theF.
freedom of motion of the compressor’s drawbar and/
or coupling device, in or on the towing vehicle’s
coupling device and/or adjacent structure whether
towing forward or backing up, regardless of the
terrain being traversed.
DO NOTG. permit personnel to ride in or on the
compressor.
Make sure the area behind, in front of, and under theH.
compressor is clear of all personnel and obstructions
prior to towing in any direction.
DO NOTI. permit personnel to stand or ride on the
drawbar, or to stand or walk between the compressor
and the towing vehicle.
Parking Or Locating Compressor
Park or locate compressor on a level surface, ifA.
possible. If not, park or locate compressor across
grade so the compressor does not tend to roll
downhill. DO NOT park or locate compressor on
grades exceeding 15 (27%).
Make sure compressor is parked or located on a rm B.
surface that can support its weight.
Park or locate compressor so the wind, if any, tendsC.
to carry the exhaust fumes and radiator heat away
from the compressor air inlet openings, and also
where the compressor will not be exposed to
excessive dust from the work site.
On steerable models, park compressor with frontD.
wheels in straight-ahead position.
Set parking brakes and disconnect breakaway switchE.
cable and all other interconnecting electrical and/or
brake connections, if provided.
Block or chock both sides of all wheels.F.
If provided, unhook chains and remove them from theG.
points of chain attachment on the towing vehicle,
then hook chains to bail on drawbar or wrap chains
around the drawbar and hook them to themselves to
keep chains off the ground which might accelerate
rusting.

4
SECTION 1
Lower front screw jack and/or any front and rearH.
stabilizer legs. Make sure the surface they contact
has sufcient load bearing capability to support the
weight of the compressor.
If a caster wheel is provided on the screw jack, it isI.
part of the screw jack and cannot be removed. Follow
the same procedure for stowing away the wheeled
jack as you would for the standard screw jack. Raise
the screw jack to its full upright position and pull the
pin connecting the jack to the drawbar. Rotate the
screw jack to its stowed position, parallel to the
drawbar and reinsert the pin. Make sure the jack is
secured in place prior to towing.
Disconnect coupling device, keeping hands andJ.
ngers clear of all pinch points. If the compressor is
provided with a drawbar, DO NOT attempt to lift the
drawbar or if hinged, to raise it to the upright position
by hand, if the weight is more than you can safely
handle. Use a screwjack or chain fall if you cannot lift
or raise the drawbar without avoiding injury to
yourself or others.
When possible, stow hinged drawbar in the verticalK.
upright position. Make certain it is securely latched in
the vertical upright position. Keep feet clear of
drawbar at all times to avoid crushing accidents in
case it should slip from your hands or otherwise fall
to the ground.
Move the towing vehicle well clear of the parkedL.
compressor and erect hazard indicators, barricades
and/or ares (if at night) if compressor is parked on or
adjacent to public roads. Park so as not to interfere
with trafc.
PRESSURE RELEASE1.3
Open the pressure relief valve at least weekly toA.
make sure it is not blocked, closed, obstructed or
otherwise disabled.
Install an appropriate ow-limiting valve between the B.
compressor service air outlet and the shutoff (throttle)
valve, when an air hose exceeding 1/2" (13 mm)
inside diameter is to be connected to the shutoff
(throttle) valve, to reduce pressure in case of hose
failure, per OSHA Standard 29 CFR 1926.302 (b) (7)
or any applicable Federal, State and Local codes,
standards and regulations.
When the hose is to be used to supply a manifold,C.
install an additional appropriate ow-limiting valve
between the manifold and each air hose exceeding
1/2" (13 mm) inside diameter that is to be connected
to the manifold to reduce pressure in case of hose
failure.
Provide an appropriate ow-limiting valve for each D.
additional 75 feet (23 m) of hose in runs of air hose
exceeding 1/2" (13 mm) inside diameter to reduce
pressure in case of hose failure.
Flow-limiting valves are listed by pipe size and ratedE.
CFM. Select appropriate valve accordingly.
DO NOTF. use tools that are rated below the maximum
rating of this compressor. Select tools, air hoses,
pipes, valves, lters and other ttings accordingly. DO
NOT exceed manufacturer’s rated safe operating
pressures for these items.
Secure all hose connections by wire, chain or otherG.
suitable retaining device to prevent tools or hose
ends from being accidentally disconnected and
expelled.
Open uid ller cap only when compressor is not H.
running and is not pressurized. Shut down the
compressor and bleed the sump (receiver) to zero
internal pressure before removing the cap.
WARNING
This equipment may be tongue heavy.
DO NOT attempt to raise or lower the
drawbar by hand if the weight is more
than you can safely handle.
NOTE
While not towed in the usual sense of
the word, many of these instructions
are directly applicable to skid-
mounted portable air compressors as
well.
CAUTION
Retract the front screw jack only
after attaching the compressor to the
tow vehicle. Raise the screw jack to
its full up position and pull the pin
connecting the jack to the drawbar.
Rotate the screw jack to its stowed
position, parallel to the drawbar, and
reinsert the pin. Make sure the jack is
secured in place prior to towing.
On two-wheeled models, fully
retract front screw jack and any rear
stabilizer legs. If a caster wheel is
provided on the screw jack it is part
of the screw jack and can not be
removed. Follow the same procedure
for stowing away the wheeled jack
as you would for the standard screw
jack. Pull the pin connecting the jack
to the drawbar and raise the screw
jack to its full up position. Rotate the
screw jack to its stowed position,
parallel to the drawbar, and reinsert
the pin. Make sure the jack is secured
in place prior to towing.

5
SAFETY
Vent all internal pressure prior to opening any line,I.
tting, hose, valve, drain plug, connection or other
component, such as lters and line oilers, and before
attempting to rell optional air line anti-icer systems
with antifreeze compound.
Keep personnel out of line with and away from theJ.
discharge opening of hoses, tools or other points of
compressed air discharge.
DO NOTK. use air at pressures higher than 30 psig (2.1
bar) for cleaning purposes, and then only with
effective chip guarding and personal protective
equipment per OSHA Standard 29 CFR 1910.242 (b)
or any applicable Federal, State and Local codes,
standards and regulations.
DO NOTL. engage in horseplay with air hoses as death
or serious injury may result.
This equipment is supplied with an ASME designedM.
pressure vessel protected by an ASME rated relief
valve. Lift the handle once a week to make sure the
valve is functional. DO NOT lift the handle while
machine is under pressure.
If the machine is installed in an enclosed area it isN.
necessary to vent the relief valve to the outside of the
structure or to an area of non-exposure.
DO NOTO. remove radiator ller cap until the coolant
temperature is below its boiling point. Then loosen
cap slowly to its stop to relieve any excess pressure
and make sure coolant is not boiling before removing
cap completely. Remove radiator ller cap only when
cool enough to touch with a bare hand.
The ethyl ether in the replaceable cylinders used inP.
diesel ether starting aid systems (optional) is under
pressure. DO NOT puncture or incinerate those
cylinders. DO NOT attempt to remove the center
valve core or side pressure relief valve from these
cylinders regardless of whether they are full or empty.
If a manual blowdown valve is provided on theQ.
receiver, open the valve to ensure all internal
pressure has been vented prior to servicing any
pressurized component of the compressor air/uid
system.
FIRE AND EXPLOSION1.4
Refuel at a service station or from a fuel tankA.
designed for its intended purpose. If this is not
possible, ground the compressor to the dispenser
prior to refueling.
Clean up spills of fuel, uid, battery electrolyte or B.
coolant immediately if such spills occur.
Shut off air compressor and allow it to cool. ThenC.
keep sparks, ames and other sources of ignition
away and DO NOT permit smoking in the vicinity
when adding fuel, or when checking or adding
electrolyte to batteries, or when checking or adding
uid, or when checking diesel engine ether starting
aid systems or replacing cylinders, or when relling
air line anti-icer systems antifreeze compound.
DO NOTD. permit liquids, including air line anti-icer
system antifreeze compound or uid lm, to
accumulate on bottom covers or on, under or around
acoustical material, or on any external or internal
surfaces of the air compressor. Wipe down using an
aqueous industrial cleaner or steam clean as
required. If necessary, remove acoustical material,
clean all surfaces and then replace acoustical
material. Any acoustical material with a protective
covering that has been torn or punctured should be
replaced immediately to prevent accumulation of
liquids or uid lm within the material. DO NOT use
ammable solvents for cleaning purposes.
Disconnect the grounded (negative) batteryE.
connection prior to attempting any repairs or cleaning
inside the enclosure. Tag the battery connections so
others will not unexpectedly reconnect it.
Keep electrical wiring, including the battery terminalsF.
and other terminals, in good condition. Replace any
wiring that has cracked, cut abraded or otherwise
degraded insulation or terminals that are worn,
discolored or corroded. Keep all terminals clean and
tight.
Turn off battery charger before making or breakingG.
connections to the battery.
Keep grounded conductive objects such as toolsH.
away from exposed live electrical parts such as
terminals to avoid arcing which might serve as a
source of ignition.
Replace damaged fuel tanks or lines immediatelyI.
rather than attempt to weld or otherwise repair them.
DO NOT store or attempt to operate the compressor
with any known leaks in the fuel system. Tag the
compressor and render it inoperative until repair can
be made.
Remove any acoustical material or other material thatJ.
may be damaged by heat or that may support
combustion prior to attempting weld repairs. Remove
diesel engine ether starting aid cylinders and air line
anti-icer system components containing antifreeze
compound, prior to attempting weld repairs in any
place other than the fuel system. DO NOT weld on or
near the fuel system.
Keep a suitable, fully charged class BC or ABC re K.
extinguisher or extinguishers nearby when servicing
and operating the compressor.
Keep oily rags, trash, leaves, litter or otherL.
combustibles out of and away from the compressor.
Open all access doors and allow the enclosure toM.
ventilate thoroughly prior to attempting to start the
engine.
DO NOTN. operate compressor under low overhanging
leaves or permit such leaves to contact hot exhaust
system surfaces when operating the compressor in
forested areas.

6
SECTION 1
Ethyl ether used in diesel engine ether starting aidO.
systems is extremely ammable. Change cylinders,
or maintain or troubleshoot these systems only in
well-ventilated areas away from heat, open ame or
sparks. DO NOT install, store or otherwise expose
ether cylinders to temperatures above 160 F (71 C).
Remove ether cylinder from the compressor when
operating in ambient temperatures above 60 F (16 C).
DO NOTP. attempt to use ether as a starting aid in
gasoline engines or diesel engines with glow plugs as
serious personnel injury or property damage may
result.
DO NOTQ. spray ether into compressor air lter or into
an air lter that serves both the engine and the
compressor as serious damage to the compressor or
personal injury may result.
Antifreeze compound used in air line anti-icerR.
systems contains methanol which is ammable. Use
systems and rell with compound only in well-
ventilated areas away from heat, open ames or
sparks. DO NOT expose any part of these systems or
the antifreeze compound to temperatures above
150 F (66 C). Vapors from the antifreeze compound
are heavier than air. DO NOT store compound or
discharge treated air in conned or unventilated
areas. DO NOT store containers of antifreeze
compound in direct sunlight.
Store ammable uids and materials away from your S.
work area. Know where re extinguishers are and
how to use them, and for what type of re they are
intended. Check readiness of re suppression
systems and detectors if so equipped.
MOVING PARTS1.5
Keep hands, arms and other parts of the body andA.
also clothing away from belts, pulleys and other
moving parts.
DO NOTB. attempt to operate the compressor with the
fan or other guards removed.
Wear snug-tting clothing and conne long hair when C.
working around this compressor, especially when
exposed to hot or moving parts inside the enclosure.
Keep access doors closed except when makingD.
repairs or adjustments, performing service or when
starting or stopping the compressor.
Make sure all personnel are out of and clear of theE.
compressor prior to attempting to start or operate it.
Shut off engine before adding fuel, uid, coolant F.
lubricants, air line antifreeze compound or battery
electrolyte, or before replacing ether starting aid
cylinders.
Disconnect the grounded negative battery connectionG.
to prevent accidental engine operation prior to
attempting repairs or adjustments. Tag the battery
connection so others will not unexpectedly reconnect
it.
When adjusting the controls, it may require operationH.
of the equipment during adjustment. DO NOT come
in contact with any moving parts while adjusting the
control regulator and setting the engine RPM. Make
all other adjustments with the engine shut off. When
necessary, make adjustment, other than setting
control regulator and engine RPM, with the engine
shut off. If necessary, start the engine and check
adjustment. If adjustment is incorrect, shut engine off,
readjust, then restart the engine to recheck
adjustment.
Keep hands, feet, oors, controls and walking I.
surfaces clean and free of uid, water, antifreeze or
other liquids to minimize possibility of slips and falls.
HOT SURFACES, SHARP EDGES1.6
AND SHARP CORNERS
Avoid bodily contact with hot uid, hot coolant, hot A.
surfaces and sharp edges and corners.
Keep all parts of the body away from all points of airB.
discharge and away from hot exhaust gases.
Wear personal protective equipment including glovesC.
and head covering when working in, on or around the
compressor.
Keep a rst aid kit handy. Seek medical assistance D.
promptly in case of injury. DO NOT ignore small cuts
and burns as they may lead to infection.
TOXIC AND IRRITATING1.7
SUBSTANCES
DO NOTA. use air from this compressor for respiration
(breathing) except in full compliance with OSHA
Standards 29 CFR 1920 and any other Federal, State
or Local codes or regulations.
DO NOTB. use air line anti-icer systems in air lines
supplying respirators or other breathing air utilization
equipment and DO NOT discharge air from these
systems into unventilated or other conned areas.
DANGER
INHALATION HAZARD!
Death or serious injury can result
from inhaling compressed air without
using proper safety equipment.
See OSHA standards and/or any
applicable Federal, State, and Local
codes, standards and regulations on
safety equipment.

7
SAFETY
Operate the compressor only in open or well-C.
ventilated areas.
If the compressor is operated indoors, dischargeD.
engine exhaust fumes outdoors.
Locate the compressor so that exhaust fumes are notE.
apt to be carried towards personnel, air intakes
servicing personnel areas or towards the air intake of
any portable or stationary compressor.
Fuels, uids, coolants, lubricants and battery F.
electrolyte used in the compressor are typical of the
industry. Care should be taken to avoid accidental
ingestions and/or skin contact. In the event of
ingestion, seek medical treatment promptly. DO NOT
induce vomiting if fuel is ingested. Wash with soap
and water in the event of skin contact.
Wear an acid-resistant apron and a face shield orG.
goggles when servicing the battery. If electrolyte is
spilled on skin or clothing, immediately ush with
large quantities of water.
Ethyl ether used in diesel engine ether starting aidH.
systems is toxic, harmful or fatal if swallowed. Avoid
contact with the skin or eyes and avoid breathing the
fumes. If swallowed, DO NOT induce vomiting, but
call a physician immediately.
Wear goggles or a full face shield when testing etherI.
starting aid systems or when adding antifreeze
compound to air line anti-icer systems. Keep
openings of valve or atomizer tube of ether starting
aid system pointed away from yourself and other
personnel.
If ethyl ether or air line anti-icer system antifreezeJ.
compound enters the eyes or if fumes irritate the
eyes, they should be washed with large quantities of
clean water for 15 minutes. A physician, preferably
any eye specialist, should be contacted immediately.
DO NOTK. store ether cylinders or air line anti-icer
system antifreeze compound in operator’s cabs or in
other similar conned areas.
The antifreeze compound used in air line anti-icerL.
systems contains methanol and is toxic, harmful or
fatal if swallowed. Avoid contact with the skin or eyes
and avoid breathing the fumes. If swallowed, induce
vomiting by administering a tablespoon of salt in each
glass of clean warm water until vomit is clear, then
administer two tablespoons of baking soda in a glass
of clean water. Have patient lay down and cover eyes
to exclude light. Call a physician immediately.
ELECTRICAL SHOCK1.8
Keep the towing vehicle or equipment carrier,A.
compressor hoses, tools and all personnel at least 10
feet (3 m) from power lines and buried cables.
Keep all parts of the body and any hand-held tools orB.
other conductive objects away from exposed live
parts of electrical system. Maintain dry footing, stand
on insulating surfaces and DO NOT contact any other
portion of the compressor when making adjustments
or repairs to exposed live parts of the electrical
system.
Attempt repairs only in clean, dry and well-lighted andC.
ventilated areas.
Stay clear of the compressor during electrical storms!D.
It can attract lightning.
LIFTING1.9
If the compressor is provided with a lifting bail, thenA.
lift by the bail provided. If no bail is provided, then lift
by sling. Compressors to be air lifted by helicopter
must not be supported by the lifting bail, but by slings
instead. In any event, lift only in full compliance with
OSHA Standards 29 CFR 1910 subpart N or any
other Local, State, Military and Federal regulations
that may apply.
Inspect lifting bail and points of attachment forB.
cracked welds and for cracked, bent, corroded or
otherwise degraded members and for loose bolts or
nuts prior to lifting.
Make sure entire lifting, rigging and supportingC.
structure has been inspected, is in good condition
and has a rated capacity of at least the net weight of
the compressor plus an additional 10% allowance for
weight of snow, ice, mud or stored tools and
equipment. If your are unsure of the weight, then
weigh compressor before lifting.
Make sure lifting hook has a functional safety latch orD.
equivalent, and is fully engaged and latched on the
bail.
Use guide ropes or equivalent to prevent twisting orE.
swinging of the compressor once it has been lifted
clear of the ground.
DO NOTF. attempt to lift in high winds.
Keep all personnel out from under and away from theG.
compressor whenever it is suspended.
Lift compressor no higher than necessary.H.
Keep lift operator in constant attendance wheneverI.
compressor is suspended.
Set compressor down only on a level surface capableJ.
of supporting at least its net weight plus an additional
10% allowance for the weight of snow, ice, mud or
stored tools and equipment.
If the compressor is provided with parking brakes,K.
make sure they are set, and in any event, block or
chock both sides of all running wheels before
disengaging the lifting hook.

8
SECTION 1
ENTRAPMENT1.10
Make sure all personnel are out of compressor beforeA.
closing and latching enclosure doors.
If the compressor is large enough to hold a man andB.
if it is necessary to enter it to perform service
adjustments, inform other personnel before doing so,
or else secure the access door in the open position to
avoid the possibility of others closing and possibly
latching the door with personnel inside.
JUMP STARTING1.11
Observe all safety precautions mentioned elsewhereA.
in this manual.
Batteries may contain hydrogen gas which isB.
ammable and explosive. Keep ames, sparks and
other sources of ignition away.
Batteries contain acid which is corrosive andC.
poisonous. DO NOT allow battery acid to contact
eyes, skin, fabrics or painted surfaces as serious
personal injury or property damage could result.
Flush any contacted areas thoroughly with water
immediately. Always wear an acid-resistant apron and
face shield when attempting to jump start the
compressor.
Remove all vent caps (if so equipped) from theD.
battery or batteries in the compressor. DO NOT
permit dirt or foreign matter to enter the open cells.
Check uid level. If low, bring uid to proper level E.
before attempting to jump start (not applicable to
maintenance-free batteries).
DO NOTF. attempt to jump start if uid is frozen or
slushy. Bring batteries up to at least 60 F (16 C)
before attempting to jump start or it may explode.
Cover open cells of all compressor batteries with cleanG.
dampened cloths before attempting to jump start.
Attempt to jump start only with a vehicle having aH.
negative ground electrical system with the same
voltage, and is also equipped with a battery or
batteries of comparable size or larger than supplied in
the compressor. DO NOT attempt to jump start using
motor generator sets, welders or other sources of DC
power as serious damage may result.
Bring the starting vehicle alongside the compressor,I.
but DO NOT permit metal to metal contact between
the compressor and the starting vehicle.
Set the parking brakes of both the compressor (ifJ.
provided) and the starting vehicle or otherwise block
both sides of all wheels.
Place the starting vehicle in neutral or park, turn off allK.
non-essential accessory electrical loads and start its
engine.
Use only jumper cables that are clean, in goodL.
condition and are heavy enough to handle the starting
current.
Avoid accidental contact between jumper cableM.
terminal clips or clamps and any metallic portion of
either the compressor or the starting vehicle to
minimize the possibility of uncontrolled arcing which
might serve as a source of ignition.
Positive battery terminals are usually identied by a N.
plus (+) sign on the terminal and the letters POS
adjacent to the terminal. Negative battery terminals
are usually identied by the letters NEG adjacent to
the terminal or a negative (-) sign.
Connect one end of a jumper cable to the positiveO.
(POS) (+) battery terminal in the starting vehicle.
When jump starting 24V compressors and if the
starting vehicle is provided with two (2) 12V batteries
connected in series, connect the jumper cable to the
positive (POS) (+) terminal of the ungrounded battery.
Connect the other end of the same jumper cable toP.
the positive (POS) (+) terminal of the starter motor
battery in the compressor, or when jump starting 24V
compressor, to the positive (POS) (+) terminal of the
ungrounded battery in the compressor.
Connect one end of the other jumper cable to theQ.
grounded negative (NEG) (-) terminal of the battery in
the starting vehicle. When jump starting 24V
compressors and if the starting vehicle is provided
with two (2) 12V batteries connected in series,
connect the jumper cable to the negative (NEG) (-)
terminal of the grounded battery.
Check your connections.R. DO NOT attempt to start a
24V compressor with one 12V battery in the starting
vehicle. DO NOT apply 24V to one 12V battery in the
compressor.
Connect the other end of this same jumper cable to aS.
clean portion of the compressor engine block away
from fuel lines, the crank case breather opening and
the battery.
Start the compressor in accordance with normalT.
procedure. Avoid prolonged cranking.
Allow the compressor to warm up. When theU.
compressor is warm and operating smoothly at
normal idle RPM, disconnect the jumper cable from
the engine block in the compressor, then disconnect
the other end of this same cable from the grounded
negative (NEG) (-) terminal of the battery in the
starting vehicle. Then disconnect the other jumper
cable from the positive (POS) (+) terminal of the
battery in the compressor, or if provided with two (2)
12V batteries connected in series, from the
ungrounded battery in the compressor, and nally,
disconnect the other end of this same jumper cable
from the positive (POS) (+) terminal of the battery in
the starting vehicle or from the positive (POS) (+)
terminal of the ungrounded battery in the starting
vehicle, if it is provided with two (2) 12V batteries
connected in series.

9
SAFETY
Remove and carefully dispose of the dampenedV.
cloths, as they may now be contaminated with acid,
then replace all vent caps.
CALIFORNIA PROPOSITION 651.12
IMPLEMENTATION OF1.13
LOCKOUT/TAGOUT
The energy control procedure denes actions necessary
to lockout a power source of any machine to be repaired,
serviced or set-up, where unexpected motion, or an
electrical or other energy source, would cause personal
injury or equipment damage. The power source on any
machine shall be locked out by each employee doing the
work except when motion is necessary during setup,
adjustment or trouble-shooting.
The established procedures for the application ofA.
energy control shall cover the following elements and
actions and shall be initiated only by Authorized
Persons and done in the following sequence:
Review the equipment or machine to be locked1.
and tagged out.
Alert operator and supervisor of which machine is2.
to be worked on, and that power and utilities will
be turned off.
Check to make certain no one is operating the3.
machine before turning off the power.
Turn off the equipment using normal shutdown4.
procedure.
Disconnect the energy sources:5.
Air and hydraulic lines should be bled,a.
drained and cleaned out. There should be no
pressure in these lines or in the reservoir
tanks. Lockout or tag lines or valves.
Any mechanism under tension or pressure,b.
such as springs, should be released and
locked out or tagged.
Block any load or machine part prior toc.
working under it.
Electrical circuits should be checked withd.
calibrated electrical testing equipment and
stored energy and electrical capacitors
should be safely discharged.
Lockout and/or Tagout each energy source using6.
the proper energy isolating devices and tags.
Place lockout hasp and padlock or tag at the
point of power disconnect where lockout is
required by each person performing work. Each
person shall be provided with their own padlock
and have possession of the only key. If more
than one person is working on a machine each
person shall afx personal lock and tag using a
multi-lock device.
Tagout devices shall be used only when power7.
sources are not capable of being locked out by
use of padlocks and lockout hasp devices. Name
of person afxing tag to power source must be on
tag along with date tag was placed on power
source.
Release stored energy and bring the equipment8.
to a “zero mechanical state”.
Verify Isolation: Before work is started, test9.
equipment to ensure power is disconnected.
General SecurityB.
The lock shall be removed by the “Authorized”1.
person who put the lock on the energy-isolating
device. No one other than the person/persons
placing padlock ad lockout hasp on power shall
remove padlock and lockout hasps and restore
power. However, when the authorized person
who applied the lock is unavailable to remove it
his/her Supervisor may remove padlock/padlocks
and lockout hasps and restore power only if it is
rst:
veried that no person will be exposed to a.
danger.
veried that the “Authorized” person who b.
applied the device is not in the facility.
noted that all reasonable efforts to contactc.
the “Authorized” person have been made to
inform him or her that the lockout or tagout
device has been removed.
ensured that the “Authorized” person isd.
notied of lock removal before returning to
work.
Tagout System—Tags are warning devices2.
afxed at points of power disconnect and are not
to be removed by anyone other that the person
placing tag on power lockout. Tags shall never be
by-passed, ignored, or otherwise defeated.
WARNING
CALIFORNIA PROPOSITION 65
WARNING
Diesel engine exhaust and some of its
constituents are known to the State
of California to cause cancer, birth
defects and other reproductive harm.
Battery posts, terminals and related
accessories contain lead and other
compounds known to the State of
California to cause cancer and birth
defects and other reproductive harm.
Wash hands after handling.

10
SECTION 1
EXPLOSIVE ATMOSPHERE1.14
WARNING
DO NOT attempt to operate the
compressor in any classication of
hazardous environment or potentially
explosive atmosphere unless the
compressor has been specially
designed and manufactured for
that duty.

11
375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
Section 2
DESCRIPTION
INTRODUCTION2.1
The Sullair 300HH, 375, 375H, and 425 CFM Standard
and Aftercooled Portable Air Compressors offer superior
performance, reliability and require a minimal amount of
maintenance. Compared to other compressors, Sullair’s
are unique in terms of reliability and durability. Compressor
internal components require no routine maintenance
inspections.
DESCRIPTION OF COMPONENTS2.2
Figure 2-1 shows the main components and
subassemblies of the Sullair 300HH, 375, 375H, and 425
Standard and Aftercooled Portable Air Compressors.
These packages include a heavy duty rotary screw air
compressor, a diesel engine, fuel tank, compressor
inlet system, compressor cooling and lubrication
system, compressor discharge system, capacity
control system, instrument panel and electrical
system. A low prole canopy offers improved handling and
mobility. Large side service doors provide easy access to
all serviceable components. This model meets EPA sound
level regulations of 76dbA at 7 meters (23 feet). Sullair air
compressors have the following delivery capacities:
Model 300HH, 300CFM@ 200 psig (13.8 bar)
Model 375, 375CFM @ 100 psig (6.9 bar)
Model 375H, 375CFM @ 150 psig (10.3 bar)
Model 425, 425CFM @ 100 psig (6.9 bar)

12 375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
SECTION 2
Radiator/Fluid Cooler Assembly1.
Radiator/Fluid Cooler Assembly With Air To Air Aftercooler2.
Lifting Bail3.
Engine Air Filter4.
Compressor Air Filter5.
Fuel Tank6.
Battery Shutoff Switch7.
Service Valves8.
Serial Number Plate Location9.
Receiver/Sump Tank10.
Minimum Pressure/Check Valve11.
Engine Exhaust Mufer12.
Moisture Separator13.
Optional Discharge Air Filters14.
Figure 2-1: Sullair Rotary Screw Portable Air Compressor – Caterpillar Standard and Aftercooled Models
The control system can easily be adjusted for pressures
from 80 to 125 psig (5.6 to 8.6 bar) for standard machines,
from 80 to 150 psig (5.6 to 10.3 bar) for “H” machines and
from 80 psig to 200 psig (5.6 to 13.8 bar) for “HH”
machines. The compressor unit is driven by an industrial
diesel engine designed to provide enough horsepower to
provide an adequate reserve under rated conditions.
Refer to the Engine Operator’s Manual for a more
detailed description of the engine. The engine cooling
system is comprised of a radiator, charge air cooler, high
capacity fan, and thermostat. The high capacity fan pushes
air through the radiator to maintain the engine’s specied
operating temperature. The same fan also cools the uid in
the compressor cooling and lubrication system.
SU_0000673

13
375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
DESCRIPTION
The engine radiator, charge air cooler, and the compressor
uid cooler are next to each other allowing the fan air to
push through all three simultaneously. As air passes
through the uid cooler, the heat of compression is
removed from the uid. The compressor’s high capacity
fuel tank contains enough fuel for one eight hour shift
under normal operating conditions.
SULLAIR COMPRESSOR UNIT,2.3
FUNCTIONAL DESCRIPTION
Sullair compressors are single-stage, positive
displacement, ood lubricated-type compressors that
provide continuous (pulse-free) compression to meet
various demand loads. Sullair compressors require no
routine maintenance or inspection of their internal parts or
systems. The compressor works by injecting uid into the
compressor unit where it mixes directly with the air as the
rotors turn: the rotor’s rotation compresses the air. The
uid ow has three main functions:
It acts as a coolant, to control the rise of air1.
temperature which is generated by compression (heat
of compression).
Seals the leakage paths between the rotors and the2.
stator and also between the rotors themselves.
Lubricates the rotors allowing one rotor to directly3.
drive the other.
After the air uid mixture is discharged from the
compressor unit, the uid is separated from the air. At this
time, the air ows to the service line and the uid is cooled
in preparation for re-injection.
COMPRESSOR COOLING2.4
AND LUBRICATION SYSTEM,
FUNCTIONAL DESCRIPTION
Refer to Figure 2-2. The compressor cooling and
lubrication system is designed to provide adequate
lubrication as well as maintain the proper operating
temperature of the compressor. In addition to the uid
cooler and interconnecting piping, the system consists also
of three other components: a uid lter, thermal valve, and
a fan which perform the following functions:
The uid lter removes and collects any contaminants •
in the uid.
The thermal valve functions as a temperature•
regulator directing uid either to the cooler or to the
compressor unit.
The fan pushes air through the cooler dissipating the•
heat resulting from compression of the uid.
The functions of the lubrication system are explained in
more detail below. Fluid is used in the system as a coolant
and as a lubricant: the sump serves as the uid reservoir.
At start-up, uid ows from the sump to the uid thermal
valve. Fluid circulation is achieved by forcing the uid from
the high pressure region of the sump to a lower pressure
area in the compressor unit. A minimum pressure device
(See Compressor Discharge System, Functional
Description on page 14) is provided to assure adequate
uid ow under all conditions. When entering the thermal
valve upon start-up, the uid temperature is cool and thus
it is not necessary to route it through the cooler. The uid
ows through the uid lter and on to the compressor unit
bypassing the cooler. As the compressor continues to
operate, the temperature of the uid rises and the
thermostatic control opens, allowing a portion of the uid
into the cooler.
When the temperature reaches 155°F (68°C), the
thermostat is fully open allowing all uid entering the
thermal valve to ow to the cooler.
The cooler is a radiator type that works in concert with the
engine fan. The fan pushes air through the cooler
removing the heat from the uid. From the cooler, the uid
is then routed back through the uid lter. All uid owing
to the compressor unit passes through this lter. The uid
leaving the lter ows to the compressor unit where it
lubricates, seals and cools the compression chamber; and
lubricates the bearings and gears.
Fluid Cooler1.
Engine2.
Compressor3.
Thermal Valve4.
Fluid Filter5.
Receiver Tank6.
Figure 2-2: Compressor Cooling and Lubrication
System
3
2
1
4
5
6
SU_0000664

14 375 Caterpillar Standard and Aftercooled/Filtered Operator’s Manual and Parts List
SECTION 2
2.5 COMPRESSOR DISCHARGE
SYSTEM, FUNCTIONAL
DESCRIPTION
Refer to Figure 2-3. The Sullair compressor unit
discharges a compressed air/uid mixture into the sump.
The sump has three functions:
It acts as a primary uid separator.1.
Serves as the compressor uid reservoir.2.
Houses the air/uid separator.3.
The compressed air/uid mixture enters the sump and is
directed against the side of the sump. Because of a
change of direction and reduction of velocity, large droplets
of uid separate and fall to the bottom of the sump. The
small amount of uid remaining in the compressed air
collects on the surface of the separator element as the
compressed air ows through the separator. As more uid
collects on the element surface, it then ows to the bottom
of the separator. A return line (or scavenge tube) leads
from the bottom of the separator element to the inlet region
of the compressor unit. Fluid collecting on the bottom of
the separator element is returned to the compressor by the
pressure difference between the area surrounding the
separator element and the compressor inlet. An orice
(protected by a strainer) is included in this return line to
assure proper and unobstructed ow. The sump is ASME
code rated at 250 psig (17.1 bar) working pressure. A
minimum pressure device located downstream from the
separator, ensures a minimum receiver pressure of 80
psig (5.5 bar) during all conditions. Keeping this pressure
level stable is necessary for proper air/uid separation and
proper uid circulation. A pressure relief valve (located on
the wet side of the separator) is set to open if the sump
pressure exceeds 250 psig (17.1 bar).
Fluid is added to the sump through a capped uid ller.
CAPACITY CONTROL SYSTEM,2.6
FUNCTIONAL DESCRIPTION
Refer to Figure 2-4, Figure 2-5 or Figure 2-6. The purpose
of the control system is to regulate the amount of air intake
and match it to the demand (required output) on the
compressor. The control system consists of a pressure
regulating valve(s), air inlet valve, system blowdown valve,
engine speed control, and tubing connecting the various
components of the compressor and engine. The functional
descriptions of the control system are described by relating
them to four distinct phases of operation. They apply to
any control system with the exception of those with
specied pressures which are dependent on pressure
requirements. The given values apply to a compressor
with an operating pressure range of 100 to 110 psig (6.9 to
7.6 bar).
Start – 0 To 40 psig (0 To 2.8 Bar) Cold Start
When the compressor is started, the sump pressure
quickly rises from 0 to 40 psig (0 to 2.8 bar). During this
period the pressure regulator valve is inactive. At this
pressure range the idle warm-up control keeps the inlet
valve closed for engine idle operation. Within 30 seconds
of starting the compressor (the instrument panel
annunciator light goes off after 30 seconds) turn the
handle of the warm-up selector valve (located on the
instrument panel) from the START to the RUN position.
The inlet valve is fully open due to inlet pressure, and the
compressor operates at full capacity. When the
compressor operates at full capacity, the engine runs at full
speed.
WARNING
DO NOT remove caps, plugs
and/or other components when
the compressor is running or
pressurized. Stop the compressor
and relieve all internal pressure
before removing these items.