Superior Air Parts

Beryl D'Shannon
Powermaster Engines
Powermaster Location
Custom Engine Overhauls

  Continental and Lycoming Engines by Powermaster ®

The majority of the engines we build are Superior Engines.

When you select Powermaster to build your engine, we perform the following operations:

  • All components are manufactured or refurbished to new limit tolerances.
  • All FAA Airworthiness Directives and mandatory OEM Service Bulletins are complied with.

Bill CunninghamCrankcase:

  • Magnaflux and Ultrasonic inspected.
  • Journals micro-polished.
  • Counterweight bushings, rollers, plates, and retaining rings replaced with new parts and components.
  • Cadmium plated front flange.
  • Dynamically balance with all gears and counterweights installed.

Connecting Rods:

  • Magnaflux inspected.
  • New bushings installed in upper end.
  • Honed on centers to insure exact length on all rods.
  • Balanced in total, crank-end and piston-end weights.


  • Magnaflux inspected.
  • Backlash checked and certified.


  • Cleaned of all coatings.
  • Zyglow inspected for cracks and imperfections.
  • All cylinder deck studs removed.
  • Weld repairs performed as required.
  • Mating surfaces machined and matched.
  • Crankshaft bore centered in case relative to cylinder decks, honed to final new part dimensions.
  • Camshaft bore in case relative to cylinder decks, honed to final new part dimensions.
  • All oil passages cleaned and de-burred.
  • All cylinder deck studs replaced with new cadmium plated studs. Studs installed using Locktite and torque plate.
  • Crankcase certified.

Rocker Arms:

  • Magnaflux inspected.
  • New single-piece rocker bushing installed and cut to size square with rocker edges.
  • Rocker toe refinished and contoured.


  • New Superior Camshaft Installed.

Hydraulic Lifters:

  • New high flow lifters installed with matched bleed-down rates installed.

Transfer Collar: (if equipped)

  • New transfer collar custom fit to insure proper oil control to propeller.

Superior Millennium Cylinders:

  • All cylinders include the following:
  • Custom valve sizing for proper dimensional clearance.
  • Custom piston ring gaping at TDC for proper gap in choke area.
  • 100% new parts installed in cylinder assembly.
  • Cylinder volume tested for conformity between each cylinder at TDC.
  • Cylinders tested for air flow uniformity.

Oil Pump:

  • Oil Pump Gears are Magnaflux inspected.
  • Mating surfaces machined and finished.
  • Internal oil passages de-burred and ported for increased flow.

Finishes and Coatings:

  • Aluminum components are cleaned, bead blasted and gold Alodine coated.
  • Crankcase and sump are primed and coated with PPG high temp urethane.
  • All metal hardware is stripped, bright cadmium plated and gold iridited.

Accessories Included with Overhaul:

  • Starter drive unit (if equipped)- Overhauled and certified.
  • Starter - New starter installed.
  • Fuel Injection System (if equipped) - Replaced with Factory Overhauled unit with new injector lines.
  • Carburetor (if equipped) Overhauled and certified.
  • Magnetos - New Magnetos Installed.
  • Ignition Harness New.
  • Spark Plugs New


  • All engines are selectively hand-fit and assembled and inspected.
  • All records of repair and assembly are recorded and provided to customer at delivery.
  • Test runs are completed using test cell with custom break in propellers. All test run information is documented.
  • When installed in aircraft at our facility, aircraft is test flown and performance documented.

Log Book:

  • New AD log book is generated for engine upon completion.
  • All Airworthiness Directives and mandatory TCM Service Bulletins are complied with.


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