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Disconnect the air hose from the wrench by pushing the collar fitting on the air hose away from the tool while pulling the air hose straight out of the tool.
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Hold the tool with the air inlet -- usually located in the bottom of the hand grip -- facing upward.
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Squeeze the trigger and hold it in.
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Squeeze one or two drops of light motor oil into the air inlet hole.
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Release the trigger. Wipe up any spilled oil from the exterior of the tool with a rag.
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