Sometime in the early part of 1923, the Hercules Corporation introduced the 1-1/2 HP Model N engine. The Model N was a departure from the typical Hercules-built 1-1/2 HP engines in that it was lighter in weight than previous engines and it sold for $10 less than the previous 1-1/2 HP Hercules engines. It was also a departure from the typical 1-1/2 HP design.
The first illustration is taken from the Hercules News, a company publication Hercules sent to dealers. The illustration shows an early Model N. It has no crank handle in the flywheel, it has the one-piece side rod bracket typical of the early Wico EK trip mechanism and it has the fuel spout set forward with a 45-degree elbow to miss the flywheel. Although it can't be seen, it also has the fuel mixer that is cast integral with the head.
Photo #2: A later-style Model N showing vertical fuel spout behind the flywheel. This unit also has the more commong two-piece side rod bracket for the magneto trip.
The second illustration shows the later vertical fuel spout that sits in behind the flywheel and the cranking handle in the flywheel. You can also see the more common two-piece side rod bracket to hold the magneto trip. Note that no choke flap was used.
Photo #3: This head-on view (right) shows the side valve set up and slanted rocker arm used on the Model N.
The third illustration shows the side-by-side valve arrangement, the slanted rocker arm and the seldom-seen muffler attachment.
Photo #4: This photo shows the governor weight used on early Model N engines. Note the lack of an adjustable stop on the weight and the fuel spout just visible next to the crankshaft.
The fourth illustration shows the governor weight that was used on the earlier N Models. It has no adjustable stop on the weight. Note the repairs to the detent arm. It also shows the fuel spout coming up through the crankcase area.
Photo #5: The later-style Model N governor weight with adjustable stop. This was a problematic design, as the governor weight had a tendency to knock the arm off the detent, allowing the engine to run ungoverned.
The fifth illustration shows the later-style governor weight with the adjustable stop. It should be noted that the Model N was plagued with troubles. It wasn't unusual for the governor weight to knock the arm off of the detent, resulting in the engine running wild, disassembling as it went.
So far, I have identified 76 of the Model N - 22 of them are Hercules brand and 30 are the Economy brand. There were apparently several sold as the Jaeger brand too.
The Model N appeared in the first half of 1923, and production continued until 1926. However, most were built between 1924 and 1925. The known serial number range is 304,954 to 347,867. Although there is no good estimate, there must have been at least 5,000 of the Model N built. The only Sears catalog listing them is the spring 1924 issue. There is no other mention of them in the literature that I have seen, and I have only found one reference to parts for the later version in one manual.
Glenn Karch is a noted authority on Hercules engines. Contact him at: 20601 Old State Rd, Haubstadt, IN 47639, or e-mail at: firstname.lastname@example.org