Liberty V-12


The V-12 Liberty aircraft engine was designed in 6 days as a "top priority" project for the war.

A total of 20,478 were produced and many were still in active use as late as 1936.

It was also used as a double crankshaft 24 cylinder and experimentally as a 24 cylinder X type.

It was also produced with either spur-gear or epicyclic reduction, and inverted,

and air-cooled, and turbo-supercharged.

It was also used in Tanks and Boats.

Its vital statistics:


                            Type:                V  45deg

               RPM:                     1800

                           Cylinders:           12

               Horsepower:          400
                           Bore & Stroke:  5" x 7 "                Flying weight:         900lbs

     It is equipped with battery and distributor ignition instead of magnetos.

The 6 day design was actually the culmination of a number of years experience

                       and experimentation by the designers, Vincent and Hall, who were able to combine                            

their research results into this remarkable engine in that short time.

The 20,478 motors were produced by Packard, 6500; Lincoln, 6500;

Ford, 3950; General Motors (Cadillac and Buick divisions), 2528;

and Nordyke and Marmon, 1000.

The example here is serial number 518 produced by Ford.

The history we have indicates that it was overhauled about 1926,

 and later used by a movie production company to run a generator and

wind machines on location, and was on the set of "How the West Was Won".



Ready to disassemble


Camshaft unit is off

Intake manifold off...showing carburetors

Lower case off...showing crankshaft

Cylinders removed

Bare crankcase

Disassembling cam units

Pitted camshafts were wonderfully and quickly repaired by  Dean Kinkelaar at Effingham Regrinding  

 Holes rusted through the water jacket

Water jacket opened

Lower half of water jacket removed

YUKKY stuff inside

New jacket welded on

One cylinder finished...only 11 more to do

         Just over 4 months of cleaning and fixing.              Ready to go back together!!

Crankshaft ready to go

The crank weighs 84 lbs. plus the hub!

Crank is in!!!

Connecting rods and lower case are on

Pistons and cylinders are ready One more
Cams are on Manifolds and carburetors are on and timing marks are laid out to set the cams

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