Cushman Carburetor Choke Butterfly And Screws

When I got this Cushman, the choke cable had been disconnected from the carburetor. The previous owner said the cable was rusted stuck, which it was, but he failed to mention to me that the choke butterfly and screws were not in the carburetor. He said he'd been through the carburetor, so he knew the butterfly was missing. No matter, I was sure I could find the missing parts online. Nope. Apparently this Keihin carburetor is maybe specific to this type of engine, I don't know. The engine does start fairly easily without a choke but in the wintertime, I'm sure a choke would be helpful. So what's one to do? Why, make the missing parts, of course. Here's what I had to start with:

I happened to have a bunch of brass tags for marking things in the shop, most likely picked up from some box of junk bought at a garage sale years ago, so I didn't have to make the disc. It's maybe an 1/8th of an inch too small in diameter but I figured it would still perform adequately.

I found a chunk of 1/4-inch stainless steel rod in the shop to make the two screws. The threads in the choke shaft are an M3 x 0.50, so kind of puny. I used my 7x10 mini-lathe to do the cutting.

My 30-year-old Craftsman tap and die set had the requisite die, the smallest in its arsenal. I made the threaded part about 6mm long.

After getting the first screw roughed out and cut to length, I eyeball-centered the disc on the choke shaft, marked the first hole location with a 3/32-inch drill bit by hand, then drilled a 1/8-inch hole in the brass disc. I then installed the screw and disc onto the shaft and marked the second hole location with the 3/32-inch bit.

I disassembled things and drilled the final 1/8-inch hole through the brass disc, then assembled everything so I could cut slots in the screws with a Dremel tool and cutoff disc.

Tada. The finished product. I will be using thread locker on the screws so they don't disappear into the engine at some point.

The brass tag had a hole in it so as to hang the tag from something, but it wasn't going to hinder the proper operation of the choke butterfly, as I'd positioned it along the length of the shaft.