CALL HIM IGNITER, NOT SPARK PLUG


| May/June 1971



Robbins Engine

Courtesy of Charles R. LaDow, 3735 Trudy Lane, San Diego, California 92106.

Charles R. LaDow

3735 Trudy Lane, San Diego, California 92106

A. R. Robbins started building a full line of heavy duty marine distillate engines in 1907. Two years earlier, he had opened his machine shop at the foot of E Street in San Diego, California. Of course, all of his machine tools were operated by a maze of flat belts, driven by overhead shafts running in babbitt bearings which were in turn, driven by a gas engine next to the building. Originally from Boston where he had learned the steam engine trade, Mr. Robbins migrated to San Diego via New Orleans, Seattle and way points where he had overhauled the steam engine on various tugboats. Like many a strong-minded man, he gave in to his wife's preference for a living-place and so the gas engine business was born in San Diego.

The engines were built to order, while the shop was kept going on repair work of various kinds, including black-smithery, and in 1911, the building was moved by barge to the foot of Elm Street, where it became a carpenter shop for building boats. A two story sheet metal machine shop was added the following year and for six years, the gas engine and boat business grew in this plant. The addition of a foundry in 1918 made possible the complete manufacture of the engines in this spot, the only items 'bought out' being magnetos, carburetors, nuts-screws-and bolts, and the crankshafts (which were forged in San Francisco). Even the piston rings were cast and machined on the grounds. So, wooden boats requiring anywhere from 4 to 110 horsepower could be completely manufactured on the premises, with the exception of minor accessories. Growth of the fishing industry made this a major enterprise in San Diego at that time.

An interesting innovation on the Robbins engines was an eccentric arrangement on the rocker-arm shaft, whereby the left of the intake valves could be altered by lever, with the engine running, by as much as three-eighths of an inch, thereby increasing slow-speed economy. Other manufacturers soon produced similar devices. A reciprocating bronze cooling-water pump was a reliable feature. Nary a spark plug was seen on a Robbins engine (hence the title of this piece). Unless the mica insulation became damaged, 'changing plugs' simply meant removing the igniter (held by two nuts) and replacing the burnt-out contact point. This was made of any handy piece of one-eighth by half-inch band iron and fastened in place by a set screw. The operation took no longer than changing a spark plug and was a lot cheaper in material. Another interesting feature of the engine was removable by-pass pipes for cooling water between the water jackets of heads and cylinders. Thus, solid head gaskets could be used (all you needed was a sheet of asbestos). Blown head gaskets and trips to the parts store were unlikely things.

How reliable were these engines? Twenty years of hard fisherman service on one overhaul was the expected thing, with reasonable care. Of course, we must remember that they ranged in weight from 112 to 160 pounds per horsepower and ran at from 230 to 500 R.P.M.; nevertheless, their performance was remarkable.

Were they hard to start? They were started on gasoline; then switched to distillate. Properly adjusted (not a difficult matter), a couple of rocks of the flywheel (by hand on the small ones, by bar on the large) would send them off. On later models, compressed air on one cylinder would make them go.