I have some experience running and repairing 5 hp Frisco Standards and 5hp Hicks from the same era 1907 and up for the National Park Service collection. They were direct drive in forward with a dead simple planetary reversing gear. Any reduction gearbox will require a way over square propellor
Max rpm for that engine will be about 350-400 tops. They are happy in the 250 rpm range.
Propellers were sized by the flywheel diameter. Somewhere I have a guide book published in that era. I'll see if I can dig it up.
Standard application for these engines here on the west coast was the 27 foot Monterey boat a pretty good sized craft that evolved from the Felucca.
They tend to leak lube oil and fuel all over the place and modern gasoline has a low enough vapor point to make them dangerous in a closed vessel
more questions,
How do you regulate engine speed?
Does this start on gasoline, run on kerosene?
Does it use a Manzel oiler?
edit: Found the wee book, it fits in a shirt pocket!
friggin iphone...
(I'll try to edit/rotate these in a bit)
I might guess a 15-16 inch wheel with a 20" pitch (rare!)
(today that is steam engine stuff, any reduction gearbox will make it near impossible to find a wheel). You need a direct drive planetary reverse gear that keeps the output shaft directly in line with the crankshaft. You might find one or you might have to make one. If I remember correctly the Hicks reverse gear is about 7/8 rpm of the crankshaft. Not quite the same speed as forward. A problem with the old propellers is they get thin with age (corrosion over 100 years) and the strong power impulses can actually knock the pitch out of them reducing there effectiveness.
I love taking those old things to sea, the engine is the proverbial heartbeat. I repaired a Hicks not so long ago and captured a video of it running, I'll hunt for it and post a link.
The Hicks regulates engine speed by changing the intake valve lash; at idle the valve has about a 1/2" lash and a 1/16" opening
It uses an eccentric rocker shaft to accomplish this. Most of those old Marvel Schebler type carburetors have no butterfly and uses the intake stroke to create a vacuum in the carb float chamber which with a leather diaphragm and a foot valve acts as the fuel pump. Dead simple which makes it rather sophisticated to get tuned correctly!
(Thinking about the reverse gear, does it by any chance have a sliding camshaft that changes timing to run in reverse?)
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