by Skywatcher » Mon Apr 06, 2020 12:27 pm
Hi Lefty
Hope you are staying safe and healthy.
These engines came with either the Nikki or the Walbro carburetor, so either will work. If the Walbro carburetor is installed, then fuel line # 791805 which has a 90º bend formed in one end should be installed between the fuel filter and the carburetor. As for the key switch, yes these can be finnicky lottle so and so's. What I have done before now is to completely dismantle them, taking a picture with a digital camera or a smart phone at each stage so you have some reference for how it goes back together.
Wash all the internals out with electrical contact cleaner or brake cleaner, do not use carburetor cleaner as this will dissolve some of the plastic parts. Scrub all the contacts with a stiff bristled nylon brush (a tooth brush can work) and dry with compressed air. Next, apply a thin coating of silicone grease or silicone dielectric compound (NOT RTV SISICONE) to all the contacts and reassemble the switch making sure that all the springs and other little bits all go back the right way around into their respective places. Once reassembled. run a full continuity test between to various terminals to make sure everything is working as it should.
As for the letters on the switch terminals, my understanding is this:
B = Battery
L = Lights
S = Starter
M = Magneto
G = Ground
A1 = Accessory terminal # 1
A2 = Accessory terminal # 2
I believe that one of the accessory terminals stays hot during cranking while the other one does not. If I understand KE4 correctly, A1 stays live while cranking and A2 does not. As this is a 4 position switch, your connections should be: (correction requested if needed, thanks)
Position # 1 Off = M + G
Position # 2 Run = B + L + A1 + A2
Position # 3 Run = B + A1 + A2
Position # 4 Start = B + S + A1
Hope this points you in the right direction,
Sky
A person who sees Quality and feels it as he works is a person who cares.
A person who cares about what he sees and does is a person who's bound to have some characteristics of Quality.
Robert M. Pirsig. (Zen and the Art of Motorcycle Maintenance)