Restoration of a Smith-Langmaid Marine Engine

Marine engine before restoration

Smith-Langmaid marine engine before restoration

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75 Kendall Avenue, Framingham, MA 01701.

I acquired an old Smith-Langmaid marine engine in June 1988 after it had been an ornament in a stone wall for more than 20 years.

Fortunately an opening in the engine once occupied by an ignitor had been covered by a small metal plate, but when I attempted to turn the heavy flywheel it became obvious that the piston was frozen to the cylinder wall.

After trying several methods recommended for freeing frozen pistons without any result, the use of a welder's torch was successful and the piston came loose. The piston, connecting rod, two bearings, and the crankshaft were then removed from the engine's main frame.

The cylinder wall was smoothed with a honing tool powered by an electric drill, and after the piston rings had been removed, their grooves were cleaned.

After reinstalling the rings, the piston and connecting rod were reinstalled with some difficulty. The crankshaft and bearings were reinstalled, but a good mechanic would have replaced the bearings at this time. However, the engine was now back together again and the piston was operational.

Hose lines were connected to two fittings on the engine and after priming one of the lines and rotating the flywheel, it was determined that the engine's small water pump was operational.

Upon disassembling the brass carburetor, it was determined that something was missing. Jim Paquette of Uxbridge, Massachusetts, a machinist and owner of numerous gasoline engines, made a new needle valve and a seat for it and the carburetor became operational.

The brass parts were cleaned and their appearances were much improved by the efforts of my wife, Kay.

A new priming fitting was installed on top of the engine, a spark plug was installed on the plate covering once occupied by an ignitor, and a small Briggs & Stratton muffler was attached. A 3/16  inch thick asbestos gasket was made and installed between the frame and the spark plug plate.

The engine was bolted to a wooden framework which included a support for a former Briggs &. Stratton gasoline tank. A copper tubing line was fabricated and connected between the tank and the carburetor.

A shelf was provided in the wooden framework to hold a small magneto which, after some machine work, was coupled to the free end of the crankshaft. Ignition timing was accomplished and a vee-belt was installed between the flywheel and an electric motor which was also bolted down.

No hand cranking was done, the electric motor was used to turn the flywheel counterclockwise in order to operate the magneto in the correct direction.

A partial disassembly and cleaning of the magneto was found to be necessary, and after getting correct carburetor adjustments, the old engine came back to life and the electric motor was disconnected.

After working intermittently on this engine for two years, there was an element of satisfaction in seeing the engine in operation. However, wanting to work on other projects, I sold the engine and another small non-operating gasoline engine is now bolted to a workbench awaiting the day when, hopefully, it also will become an operational unit.

Incidentally, the Smith-Langmaid engine was built at Portland, Maine and a nameplate identifies it as being a Casco model. No information could be located on this engine and there was no response to a request carried in a Reflections column.