The Continental C115, C125 and C140 aircraft engines were manufactured by Continental Motors in the 1940s, all sharing the US military designation O-280.
These engines feature a flat-6 configuration and produce 115 hp (86 kW) 125 hp (93 kW) or 140 hp (104 kW) respectively.
The C125 has the same crankcase as the Continental C145, although the engines differ in stroke, compression ratio and carburetor jetting.
The C125 features a cast iron camshaft and hydraulic tappets.
[1] Reference: Engines for Homebuilt Aircraft & Ultralights[1]