Troy Bilt Pony Tiller Engine Replacement . Powered by a 250cc, 11.5 ohv briggs & stratton powerbuilt™ engine. H60 75482u(b) 4054d, that is what is on the plate of the engine part, the rotary part has number like th1002, th1019, 1238(73), and 1239(73). Restoring a 1977 TroyBilt Horse Tiller Painting the Engine from horserestoration.blogspot.com Complete exploded views of all the major manufacturers. The original has a 2nd pto shaft to run the reverse gear on the tiller. 4.5 out of 5 stars 152.