Hi All
With regard to the 3 1/2 hp cam box with the 14554 engine number stamped on it as shown; in
https://www.douglasmotorcycles.net/index.php?topic=5161.msg18664#msg18664 and mentioned in this thread.
I had a closer inspection the orphan cambox, the 554 number would appear to be the actual engine number as it is in typical Douglas typeface stamp. The 14 is of a different typeface and is slightly smaller which may have been added at some stage. The number 554 is in the same type face on my 1914 engine No 1783. If the actual engine number is 554 then did the numbering sequence start at 500?. I don't think the production numbers of the 3 1/2 h.p. engines was more than 1000 units. So could it be possible that when the engine was redesigned late 1913 early 1914 that the revised design started at engine number 1000.
I have not compared the 554 cambox with the 1783 cambox internally as yet to see if they are identical. but externally they are very similar, but I have noticed that the number stamped on the 554 cambox is on the rear cylinder side of the casting and not the usual front cylinder side of the casting as on the later engine. May be it was a replacement part, that was supplied and had the engine stamped on it, but not on the usual side.
Although the number 14554 is in the range of the last 4h.p. engines of late 1923. the cambox is definitely 3 1/2 h.p and not the heavier built 4 h.p. component as shown in the earlier thread.
The gearbox shown is definitely a 4 h.p.,item and probably dates around 1919-20, and the clamp shown is the correct component for attaching the gearbox to the rear of the crankcase.
Cheers Steve.L.