Aircraft Propeller Removal and Installation


The following procedure is for demonstration purposes only. Always use the current manufacturer’s information when removing and installing any propeller.
  1. Remove the spinner dome in accordance with the spinner removal procedures. Cut and remove the safety wire (if installed) on the propeller mounting studs.
  2. Support the propeller assembly with a sling. If the propeller is reinstalled and has been dynamically balanced, make an identifying mark (with a felt-tipped pen only) on the propeller hub and a matching mark on the engine flange to make sure of proper orientation during reinstallation to prevent dynamic imbalance.
  3. Unscrew the four mounting bolts from the engine bushings. Unscrew the two mounting nuts and the attached studs from the engine bushings. If the propeller is removed between overhaul intervals, mounting studs, nuts, and washers may be reused if they are not damaged or corroded. CAUTION: remove the propeller from the mounting flange with care to prevent damaging the propeller mounting studs. Using the support sling, remove the propeller from the mounting flange.
  4. Place the propeller on a cart for transport.


A flange propeller has six studs configured in a four-inch circle. Two special studs that also function as dowel pins are provided to transfer torque and index the propeller with respect to the engine crankshaft. The dowel pin locations used on a particular propeller installation are indicated in the propeller model stamped on the hub. Perform the applicable steps under Spinner Pre-Installation and clean the engine flange and propeller flange with quick dry stoddard solvent or methyl ethyl ketone (MEK). Install the O-ring in the O-ring groove in the hub bore. NOTE: When the propeller is received from the factory, the O-ring has usually been installed. With a suitable support, such as a crane hoist or similar equipment, carefully move the propeller assembly to the aircraft engine mounting flange in preparation for installation.

Install the propeller on the engine flange. Make certain to align the dowel studs in the propeller flange with the corresponding holes in the engine mounting flange. The propeller may be installed on the engine flange in a given position, or 180° from that position. Check the engine and airframe manuals to determine if either manual specifies a propeller mounting position.

CAUTION: Mounting hardware must be clean and dry to prevent excessive preload of the mounting flange.

CAUTION: Tighten nuts evenly to avoid hub damage.

Install the propeller mounting nuts (dry) with spacers. Torque the propeller mounting nuts (dry) in accordance with the proper specifications and safety wire the studs in pairs (if required by the aircraft maintenance manual) at the rear of the propeller mounting flange.