Actually, not all Model A vehicles even had a frame number. It is popularly but incorrectly claimed that the serial number of the vehicle was a frame number. The Specifications and License Data page above in the Instruction Book is quite clear and specific about this. 99T heads were used on trucks in the years 1939 to 1941.Model A Vehicle Serial Number and LocationĪs shown above in the 1928 Model A Ford Instruction Book, Ford did in fact specify the engine number to be the 'serial number' of the vehicle, during the Model A (and B) era, and throughout the 1930's. The same periode trucks used 41T cylinder heads. For example 81A cylinderheads were used from 1938 to 1942. It's important to know that the cylinderhead marks can be differend from the engine model. Modern style distributor, water outlet in front of cylinder head, fails pencil test Round distributor, water outlet on center of cylinder head, fails pencil test All post war blocks will fail the pencil test.ĭivers Helmet distributor, water outlet on center of cylinder head, passes pencil testĬrab-Style distributor, water outlet on center of cylinder head, passes pencil test The shelf is deep enough to horizontal lay a pencil on it. This pre war blocks have a tiny shelf above the timing cover. This design was keept till the end of the US flathead production line in 1953.Īll pre WW2 flathead engines, including the 21 stud, will pass the so called 'Pencil Test'. In 1949 the outlet moved to the front of the engine (left picture). 1938 to 1948 cylinders had the water outlet in the middle of the head (see right picture below). The water outlet design on the cylinder heads was changed in 1949. All three distributor styles are located on the middle of the front side of the engine.Īll 1949-up engines have a modern style distributor located on the top front of the engine. The 1946 to 1948 engines had the round style distributor. The 1942 to 1945 engines had the Crab-Style distributor (see picture below). This distributor applies to all engines from 1932 to 1941, so for the 24 stud engines we are looking at, all 1938 to 1941. The earlier models have, like all 21 stud engines, a so called Divers Helmet distributor (sometimes called Eggshell distributor). 21 stud with Divers Helmet or Eggshell Distributor

Ford engine serial number location