CP869S (T019387) Chicago Pneumatic Sander - Overview

Hi Dan, thank you for your inquiry. Based on the description of the issue, check the rotor blades, part number PS10302186. The motor relies on compressed air pushing against sliding vanes inside the rotor. If moisture has entered your air lines over time, the vanes can swell, corrode, or get stuck inside their slots. They will not slide out to catch the air, meaning the air simply blows right past them and out the exhaust. Remove the motor housing, carefully extract the rotor vanes, and clean both the vanes and their slots using a safe solvent (e.g., parts cleaner). If the vanes are chipped or deeply worn, you will need to replace the rotor blades. If the tool has sat unused or has run dry, the vanes or the motor bearings may have seized. Disconnect the air line, drop a generous amount of air tool oil (or a light penetrating oil) directly into the air inlet. Let it sit for a few minutes, reconnect the air, and see if it breaks the motor loose. Glad to be of help!