A lockout tool for an air cycle machine includes a lockout tool body threaded section, a lockout tool body end section, and a lockout tool body conical tip. The lockout tool body threaded section is operable to engage a threaded port of the air cycle machine that is proximate to a shaft of the air cycle machine. The lockout tool body end section includes a rotation interface operable to receive a rotational force to control engagement of the lockout tool body threaded section with the threaded port. The lockout tool body conical tip is operable to engage the shaft of the air cycle machine to prevent rotation of the shaft.