TEFC Motor Maintenance Guide
General maintenance is limited to keeping the motor clean, brush off or use very low pressure air (depending on what is built up on the motor).
Regreasable motors will require the installation of new grease periodically. Make sure you match the grease as listed on the nameplate. And be sure to open the grease relief plug and slowly pump the correct amount of grease. Watch for the old grease to purge out. All for complete purge then replace the grease relief plug.