The Lionel Santa Fe F-3 No. 2243 was, along with the No. 2245, the first single motored O27 F-3’s produced in 1955. This diesel would be available for one additional year and in 1958 would be produced as an O gauge engine. Painted in the Santa Fe’s "War Bonnet" passenger paint scheme, the BLACK lettering was heat-stamped on the sides. The chassis is SILVER, as is the pilot skirt on the A Unit, and the truck side frames are BLACK.

This engine has louvered roof vents, filled in portholes, cast in side ladders, and a magnetic disc coupler on the front end of the A unit. All other couplers are solid and non-operating. This diesel was equipped with a horn that was operated by a D Cell battery, and a three position directional unit whose control lever was adjustable from underneath the chassis. The single vertical worm drive motor powers two axles that utilized Magnetraction. There are three variations:

Variation A: Large cast in side ladder on A Unit.

Variation B: Small cast in side ladder on A Unit.

Variation C: The A Unit uses an ORANGE body mold.

All of the Lionel F-3’s are designed to work on the larger radius of O gauge track. When used with O27 track this diesel will scrape the switch machine housing on No. 1122 O27 switches when passing through the curved turnout. Evidence of scrapes on the fuel tank of these diesels is a sure indication of operation on O27 track.