Avia M 337

The Avia M 337 (originally designated the Walter M337) is an inverted six-cylinder air-cooled inline engine. It was developed by the Czechoslovak company as a six-cylinder derivative of the four-cylinder M 332 engine, going into production in 1960. An unsupercharged version of the M 337 is designated as the LOM M137. Production transferred to Avia in 1964, and to Letecke Opravny Malesice (LOM) in 1992.

M 337
Right side view of a Walter M337; the front cylinder is hidden by the engine cowling
Type six-cylinder inverted inline piston engine
National origin Czechoslovakia
Manufacturer Walter Aircraft Engines/Avia/LOM
Major applications Let L-200 Morava
Zlín Z 43


M 337A
Basic supercharged engine - not rated for aerobatics
M 337R
Modified for pusher installation
M 337AK
modified oil system for unlimited inverted flying. "Snap" aerobatics permitted.
M 337AK1
AK fitted with alternator instead of generator
M 337B
Increased max running speed (3000 rpm) - increased power - 175 kW (235 hp).
M 337BK
Aerobatic version of B.
M 337C
Increased compression ratio - 188 kW (252 hp)
M 137A
Unsupercharged version of M 337 130 kW (180 hp) take-off power. Aerobatics allowed.
M 137AZ
As M 137A, with filtered air feed
M 437
Gear ratio 0.7:1 180 kW (240 hp)


Specifications (M 337)

Data from Jane's All The World's Aircraft 1980-81 [1]

General characteristics

  • Type: 6-cylinder inverted air-cooled supercharged inline engine
  • Bore: 105 mm (4.13 in)
  • Stroke: 115mm (4.53 in)
  • Displacement: 5.97 L (364.3 in³)
  • Length: 1,410 mm (55.51 in)
  • Width: 472 mm (18.58 in)
  • Height: 628 mm (24.72
  • Dry weight: 148 kg (326.3 lb)


  • Valvetrain: OHC two camshaft operated valves per cylinder, sodium filled exhaust valve
  • Supercharger: Centrifugal
  • Fuel system: Low-pressure fuel injection
  • Fuel type: Min 72-78 Octane
  • Oil system: Dry sump pressure feed system
  • Cooling system: Air-cooled



  1. J W R Taylor 1980, p.692.
  • Taylor, John W R (editor) (1980). Jane's All The World's Aircraft 1980-81. London: Jane's. ISBN 0-7106-0705-9.CS1 maint: extra text: authors list (link)
  • http://www.walterjinonice.cz/historie-spolecnosti-walter
  • http://www.pistovemotory.cz/en/engines


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.