Sure do. I had a 1941 Farmall A that I sold to a guy who had it restored. He put hydraulics on it, however.
I stlll have the vacuum cylinder, the single bottom plow and the rockshaft in the barn.
The way it works is:
When you pull on the lever, there is a linkage that connects to a device that mounts on the top of the exhaust/intake manifold. Essentially, it is a valve that has a metal flap in it. When you push the lever forward, it closes the flap and sends the exhaust gas into the hose that connects to the cylinder. That causes the cylinder to retract, lifting the implement by means of the rockshaft. When you pull the lever, it opens the flap allowing the gas to escape, lowering the implement. The cylinder is porcelain lined and has a large leather seal inside it. When the lever is in the neutral position, a check valve keeps the gas in the cylinder, "floating" the implement. The hose on my Farmall was nothing more than a black rubber hose with fittings on the ends that were just like the fittings on your garden hose. It worked pretty good. In fact, the single bottom plow is pretty heavy and it lifted it no problem.
