Lycoming WWII Production Engines
Compiled by Kimble D. McCutcheon from Material Provided by Scott Rodriguez
Published 11 Oct 2018

Lycoming's first aircraft engine, the 9-cylinder R-645, was rated at 185 hp and received Approved Type Certificate No. 27 on 30 Sep 1929. An enlarged R-680 received Approved Type Certificate No. 42 on 4 Feb 1930 and was rated at 215 hp. A 7-cylinder R-530 with a 210 hp normal rating followed on 23 Oct 1937. Lycoming's first horizontally-opposed engine, the 4-cylinder, 50 hp O-145, received its Approved Type Certificate on 13 Jun 1938. Below are images and specifications of the Lycoming engines in production during 1943.

 

Horizontally-Opposed Engines
 Takeoff RatingPropeller Overall DimensionsInstallation
ModelHPRPMFuel
Octane
Gear
Ratio
ShaftWeight
(lb)
LengthHeightWidthSpecIns
Dwg
NotesImages
O-145-A2552,300731:16-F163.11 24.6220.5929.561026450032 
O-145-A3552,300731:16-F165.34 24.6220.5929.561082450023LF
O-145-A4552,300731:16-F200.36 26.0023.0029.561083450124 
O-145-B2652,550731:16-F163.40 24.6220.5929.561035450032 
O-145-B3652,550731:16-F165.63 24.6222.5929.561084450023 
O-145-B4652,550731:16-F200.50 26.0023.0029.561085450124 
O-145-C2753,100731:16-F163.40 24.6220.5929.561028450032 
O-145-C3753,100731:16-F165.63 24.6222.5929.561086450023 
O-145-C4753,100731:16-F200.50 26.0023.0029.561087450124 
GO-145-C2753,2007327:176-F196.39 29.3120.5929.561045450052 
GO-145-C3753,2007327:176-F198.62 29.3122.5929.561088450013LF
GO-145-C4753,2007327:176-F233.49 30.6923.0029.561089450134A
O-2351002,550731:16-F239.00 30.0925.1932.321080-B602105LF, A
O-235-A1002,550731:16-F268.30 31.5425.2032.321081-A602116A
O-290-A1252,450731:18-F277.30 31.6425.4832.321079-D602087A
O-290-B1252,600731:18-F245.79 30.0926.6432.322011602158 
O-290-C1252,600731:18-F238.01 30.0926.6432.322012-C602169LF, A
O-290-D1302,800801:18-F257.00 30.0922.8132.242069637239LF, A
O-3501502,500731:1#20348.52 45.4828.0432.321076-D652145LF, A
O-350-A1502,500731:1#20372.99 45.4826.5432.321077652016A
O-435-A1752,300731:1#20384.00 46.2128.0432.32 1075-C 652017A
O-435-B2253,0001001:1#20364.66 45.1129.6132.3220166522111LF, A
O-435-C1852,450731:1#20352.15 45.4828.0432.322010-D6521810LF
O-435-T1632,800731:1 755.00 48.0732.1735.621092-B65209 R
GO-4352103,00073120:77#20394.13 47.7029.6132.3220156522010LF
GO-435-B2203,000100120:77#20401.10 47.7029.6132.3220146521911LF
Abbreviations:6-F = 6-Bolt Flange; 8-F = 8-Bolt Flange; SAE #20 = SAE #20 Spline
Notes:1. All engines were equipped with a single SAE tachometer drive.
 2. Fuel pump drive, radio shielding and mixture control were available as options.
 3. Fuel pump drive, starter drive, generator drive, radio shielding and mixture control were available as options.
 4. Equipped with Delco Remy starter and generator. Fuel pump drive, radio shielding and mixture control optional.
 5. Equipped with starter and generator drive. Dual tachometer drive, fuel pump drive, radio shielding and priming system optional.
 6. Equipped with Delco Remy starter and generator. Dual tachometer drive, fuel pump drive, radio shielding and priming system optional.
 7. Equipped with Delco Remy starter and generator. Dual tachometer drive, fuel pump drive, radio shielding, cylinder head cooling baffles and priming system optional.
 8. Equipped with starter and AN generator drive. Dual tachometer drive, fuel pump drive, radio shielding, cylinder head cooling baffles and priming system optional.
 9. Equipped with starter and generator drive. Dual tachometer drive, fuel pump drive, radio shielding, cylinder head cooling baffles and priming system optional.
 10. Equipped with starter drive, generator drive and radio shielding. Fuel pump drive, vacuum pump drive, dual tachometer drive, unshielded ignition and priming system optional.
 11. Equipped with starter drive, AN generator drive and radio shielding. Fuel pump drive, vacuum pump drive, dual tachometer drive, unshielded ignition and priming system optional.

 

Radial Engines
 Takeoff RatingNormal Rating Overall DimensionsInstallation
ModelHPRPMHPRPMFuel
Octane
Weight
(lb)
LengthDiameterSpecIns
Dwg
Notes
R-680-B4D------2252,10065492.0037.0943.50 10561610-P2
R-680-D52602,3002452,10080505.0037.0443.50 10091610-D3
R-680-D62452,3002452,10073505.0037.0443.50 10101610-D3
R-680-E12902,3002752,20080514.0037.0443.50 10211610-G3
R-680-E22802,3002652,20073514.0037.0443.50 10221610-G3
R-680-E33002,3002852,20087514.0037.0443.50 10231610-G3
R-680-E3A3002,3002852,20087515.0037.5043.50 1047-D 1610-M3
Notes:1. All engines were direct drive and equipped with a SAE No. 20 propeller shaft.
 2. Equipped with dual tachometer drive, priming system and Cuno oil filter. Fuel pump drive, generator drive, vacuum pump drive and radio shielding were available as options.
 3. Equipped with single tachometer drive, priming system, manual hydraulic propeller control unit, cylinder and head cooling baffles and Cuno oil filter. Fuel pump drive, generator drive, vacuum pump drive, dual tachometer drive, radio shielding and constant speed propeller governor drive were available as options.