Little Giant

Chain-driven Overhead Cam Engine is Long on Features but Short on History

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A close look at the overhead camshaft, ignition timer and rocker arm, which are carried in a common bracket. The bracket can be adjusted fore and aft to take up slack in the cam chain. The device on top of the cylinder and to the rear is the vacuum pump.

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I've been collecting engines since 1971, and I have hunted down engines across Ohio, Pennsylvania and New York. In February 2003, I saw an advertisement for an estate auction only 13 miles from my home. The advertisement listed an old engine. The day of the sale it was 15 degrees F outside and there was 4 inches of snow on the ground. The engine was very rusty, but I bought it anyway. When I paid the auctioneer's secretary, who I graduated from high school with, I said, "What will I say to my wife?"

Little Engine, Big Details

This little engine uses a block-type skip chain driving an overhead camshaft that operates the exhaust valve and the ignition timer. The engine appears to be of 1905-1910 vintage; the block-type skip chain (called a "skip" chain because it doesn't ride on every tooth) disappeared from use about this time. It also uses an odd Lunkenheimer carburetor.

It has make-and-break points inside the timer cover and a buzz coil to the plug. The entire front mechanism, including camshaft, rocker arm and timer, is mounted on a bracket that can be moved to tension the chain. There are guides under the bracket that allow the camshaft and everything else to be adjusted back and forth, and not tip, tilt or cock in any way while being moved. The carburetor, timing lever, timer, overhead cam, exhaust rocker arm and all adjustment pieces are made from brass.

It has a round, hollow piston rod with a brass flip-up oiler set in the rod to lubricate the wrist pin and rod bearing (the oil passes through the hollow rod), which is brass molded to the round steel rod. At 0.775", the wrist pin is an odd diameter, as a standard size would be 0.750", or 3/4-inch. It uses a single piece of 1-inch pipe for its thermo-siphon, tank-cooled system. The original water hopper is gone. The one on it is an old tank I found that has, to my eye, the right patina.

The engine base is stepped several times; it's wide at the front and narrows between the flywheels. Its odd-looking piston is 10-1/4 inches long, with a raised, 5-inch area for the integrated vacuum pump. The pump and piston create the vacuum, with pump timing controlled by the chain drive.

I have seen another engine like mine with the same base and main castings, but it has larger, wider and heavier flywheels, and a Scheibler carburetor. Another collector found a similar engine in New York with the same base. It's also an overhead cam design and chain-driven, but otherwise looks different all around. Also, on my engine where the 1/2-inch pipe threads into the head for carburetor intake, the casting is almost flat, but the other two engines have a large, protruding boss. Was the casting changed to hold the larger and heavier Scheibler carburetor? None of the engines feature a governor to control speed.

The piston rings on my engine were in good condition. They were worn some, which I liked because it told me it had run quite a bit. The back part of the piston that was outside the cylinder bore was pitted, but the rest of it was nice and clean. It was frozen, but it freed up after I soaked it for a few months. The bearings were good and I didn't replace any of them. I replaced the valves, which were in bad shape.

The engine has casting numbers ranging from no. 1 to no. 9. The bearing caps, no. 9; the flanges at the rear of the cylinder, no. 8; the flywheels, no. 5; and the main cylinder, no. 6. Some other casting numbers are hidden under the engine.

I don't believe this engine was built in a jig or anything, as all the threaded mounting holes (for the carburetor, muffler, etc.) are a little crooked. It's an interesting little engine, and I don't think whoever built and designed it was copying someone else's design or idea.

According to what I've been told, the engine was originally used on a sidewalk sweeper, probably by a hotel. A few well-known engine collectors told me it was a Little Giant: I like it for the name.

I haven't really tried to run it, but I'm sure it will run. I couldn't save the original drive chain, which was real rusty when I got it, but I looked until I found a chain that was almost exact. I can turn it over by hand, but it has a tendency to want to pick up and snap since the sprockets and chain aren't worn to each other (you want them to wear together). I'm sure if I start it it's going to bend a shaft or snap the chain. I finished it and showed it at the Portland, Ind., show last year.

I have really beat the bushes looking for old engines, so finding this engine so close to home was really exciting. I'd like to hear from anyone who might know more about this engine and who might have made it.

Contact engine enthusiast David Williams at: 155 New State Road N., Norwalk, OH 44857-9750; (419) 744-2304.