Compressor Operation - Harbor Freight Tools Central Pneumatic 40400 Assembly And Operating Instructions Manual

When unpacking, check to make sure all parts are included. Refer to the Assembly Drawing and Parts List at
the end of this manual. If any parts are missing or broken, please call Harbor Freight Tools at the number on
the cover of this manual as soon as possible.
The Wheels need to be assembled to the Air Compressor. Insert the Axle (#54) through one of the Wheels
(#55). With these two assembled together, insert Axle (#54) through the bracket on the bottom of the Tank
Assembly (#50). Slide on Washer (#56) and the Lock Washer (#57) and tighten with the Nut (#58). Once
assembled, roll the Air Compressor to test the operation of the wheels. Periodically check to insure that
wheel and axle hardware is secure.
To assist you with operation, please refer to the Assembly Diagram and Parts List located on pages 6, 7 and 8.
Warning: Fill with compressor oil before using;
running with NO or LOW OIL voids warranty.
Checking the Oil
Make certain to add compressor oil prior to operation. The Oil Fill Plug and Oil Sight is shown on the
illustration on page 6. Only use a good quality, 30-weight, non-detergent compressor oil.
Change the oil after every 500 hours of operation.
1. By checking the level of fluid in the Oil Sight (part #20), you will be able to determine the oil level. The
oil level should be even with the dot in the center of the Oil Sight (part#20). If low, add oil until it is at
the proper level.
2. Oil is added by removing the Oil Plug (part #14) and, using a funnel to avoid spills, adding oil to the
Compressor. After Oil is added, replace the Oil Plug.
1. Plug the power cord into an electrical outlet with a grounding prong.
2. Pull up on the ON/OFF switch to turn on (see illustration on page 6). Push down on the switch to shut
the compressor off.
3. Allow the tank to fill to 80 PSI before using. With the Air Compressor on, its operation is automatic
and under the control of the internal pressure switch.
Warning: Do not remove the factory sealed Air Control Valve (see illustration on page 6); removal of
this valve voids warranty.
Hose Connections
1. Close the Air Control Valve (turn to right or left).
2. Connect the high pressure air hose to the air outlet. The outlet is 1/4" NPT. Note: For easy
connection or removal, a quick coupler (not included) should be installed on the end of the outlet.
3. Turn the Air Control Valve to the middle position to allow the air to pass.
REV 03/06
SKU 40400 For technical questions, please call 1-800-444-3353.
Unpacking
Assembly
Operation

Compressor Operation

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