Mystery Inverted Engine

Thiem & Co. inverted engine offers many questions and no answers


| March 2000



The mystery engine

The mystery engine

This month's Vintage Iron photographs come from Roger Moe, Springfield, Minn. I met Roger at the Central Hawkeye Swap Meet last May at Waukee, Iowa. I had a block of an inverted Webster engine on my trailer. Roger stopped by and said he had an inverted engine that he hadn't been able to get much information on. 

The name cast on the base of his engine is Thiem & Co., St. Paul, Minn. It has a 4-1/2-inch bore and a 7-inch stroke. The crankshaft is 1-5/8 inches in diameter, and the cam shaft is 1-1/4 inches. The exhaust valve has a 5/8-inch stem and a 1-3/4-inch head. The flywheels are 28 inches in diameter, but are not the originals. He is missing the intake valve cage, valve and carburetor, which bolted on four studs opposite the engine. It looks to have been a hit-and-miss governed engine, although most of the governor parts are missing except for the latch catch on the exhaust valve cam follower. The number "2" is cast on the block. It is drilled for some kind of crankshaft shield, which is also missing. Roger did a search at libraries in St. Paul, and came up with the following listings:

1890: Edward Thiem, boilermaker for Kenny Bros.

1892: Edward Thiem, machinist for St. Paul Roofing & Cornice Works

1897: Edward A. Thiem, proprietor of Northwestern Machine & Cycle Works

1897: Thiem & Co. (bicycle specialties)