10/19/2026
I spent most of today working on this project engine I bought at Coolspring PA last week. It's a 3hp Massey Harris field sprayer engine. The sprayer pump portion is long gone but the engine lives on. This was a machinist project that just didn't get finished. He had made new valve cages and valves, and had new rings with it (not installed). The mixer was apart in the bucket and no timer contact was on it.
I started with the carburetor. A quick run to Lowes to get the 5/16" bolts I needed (minus one because apparently I can't count today). Needed to make a new tension piece for the choke rod, luckily found a cheap throw away wrench from one of those furniture kits that fit just perfectly. Drilled a hole for mounting and cut off the end, and called that piece done. Then I could reassemble the bottom of the saxophone and make a gasket to mount to the engine.
I couldn't get any compression and finally realized the new exhaust valve was a little longer than the original, so it wasn't seating. Since valves are very hard, I didn't have anything to cut it down, so I took off the walking beam pushrod and flipped the end nut around to allow the valve to close.
I pulled the piston and got the new rings in the grooves. Reassembled that, and timed the cam gear to the crank and valves. These don't have timing marks so I just tried a few spots and once it was fairly close just worked it tooth by tooth until I was happy.
Next up was the timer contact. I knew what I wanted, but didn't have any material around that I could find to make it. So, I designed it in a CAD software and 3D printed it. The first take was a little off, but the second was perfect. About 20 minutes of design work and 15 minute print time (twice), that was done. I still needed a metal strip for the wiper so resorted to an old band saw blade. I used a sand paper wheel to sand the teeth off the blade and paint, chucked it in the drill press to cut some holes for mounting and for the wire, and cut it to length. Attached that to the 3d printed insulator block, and worked on the bend to get the timing just right.
That was the last piece to be able to hook up a battery and coil, and try the engine. I squirted some gas in the carb, flipped the wheels a few times, and smoke poured out. That was enough to prove the engine will run, so next steps are just hooking up the fuel line, getting an oiler on it, and some wood skids.
Enjoy the pics and video.
