The Economy Model B Gas Engine

By Staff
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The Economy Model B gas engine, produced by the Holm Machine Mfg. Co. at Sparta, Mich., for Sears, Roebuck & Co., beginning in early 1910.
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A sheet metal fuel tank is present in the base with a cast iron funnel-shaped spout that has an outlet to the mixer.
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About midway through the Model B engine's production, the serial number tag was changed slightly, as seen in Photos 3 and 4. The more common tag used until nearly the end of production is on the bottom - Photo 4.
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This issue, I’d like to discuss the Economy Model B gas engine, which was produced by the Holm Machine Mfg. Co. at Sparta, Mich., for Sears, Roebuck & Co., beginning in early 1910.

In all, some 4,500 Model B engines were built. Their serial numbers all fall between 1500 and 6000, and currently 41 of them are known to still exist. Twenty of those are 2 HP, one is 3 HP (there is some question about this one because it’s an over-stamp), six are 4 HP, and 14 are 6 HP. Surely 8 and 10 HP sizes were produced, but none are known to exist so far.

Before the Model B, several changes were made from the earlier Economy Model A engine. The water hopper now has a ‘traditional’ flat top with a removable insert. Although mounted in a way similar to the Witry fuel system on the Model A, the fuel mixer is now an Essex. A sheet metal fuel tank is present in the base with a cast iron funnel-shaped spout that has an outlet to the mixer, as seen in photos 1 and 2 in the Image Gallery.

The flywheels are now split-hub with two clamping bolts rather than the solid hub with a gibb key. About midway through the Model B engine’s production, the serial number tag was changed slightly, as seen in photos 3 and 4. The more common tag used until nearly the end of production is on the bottom, as in photo 4.

Strangely, Sears catalogs never show a Model B engine. The catalogs show illustrations of the Model A from the spring of 1910 and move to illustrations of the Model C in the fall 1910 issue. I suspect Model B engines were shipped during most of 1910. Even engine prices in the 1910 catalogs are somewhat confusing.

Either way, the Model B engine falls right in the long line of tradition among these interesting Economy engines. Anyone owning one will agree they are special, indeed. 

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