Car Serial Numbers

•  The first Hupmobiles, the Model "20," have the car serial number on a brass plate located on the dash under the magneto switch. The matching serial number is stamped into the top of the frame cross member, on the left side under the floor boards.

• The Model "32" (or H) has the car serial numbers on the sector plate in the center of the dash. The car serial number is also located on a small steel tag located at the rear of the frame riveted in the outside center of the cross member.

• The four-cylinder Models "K" and "N" have the car numbers under the dash light, near the speedometer.

• The four-cylinder Model "R," six-cylinder Model "A" and the eight-cylinder Model "E" have the car numbers on a plate where the steering column attaches to the dash.

• The Skylark Model "R" has the car number on a plate on the right rear floor under the carpet. The serial can also be found stamped into the top of the frame on the passengers side near the shock mount.

• In addition, many of the late twenties and early thirties cars have a serial number plate attached to the top of the left frame member, about midway between the radiator and firewall. Generally the hood ledge and left fender must be removed to get at it.

• All other models have the car numbers on the plate under the hood, on the passenger side firewall.

Motor Numbers

•  The Model "20" has the motor number stamped on the top rear of the crankcase, between the cylinder block and the transmission which has the same number stamped on the matching flange.

• The Model "32" motor number is stamped on top of the starter boss on the crank case for cars equipped with electric starters.

• The four-cylinder Model "K," no information available.

• The four-cylinder Model "N" has the motor number on the right front crankcase extension, near the generator.

• The four-cylinder Model "R" has the motor number on the right front side of the block, near the generator.

• The eight-cylinder Models "E" and "M" have the motor number on the right rear motor support leg. Some may also have it on the left side of the crankcase.

• All other models have the motor number on the lower left side of the crankcase.

Important Note

•  The four-cylinder Model "R" and all six- and eight-cylinder cars have a letter prefix on the car number and the motor number.

• The car number letter prefix designates the model and is etched and painted while the numbers are stamped.

• The motor letter prefix and the numbers are stamped in.