I have a Horse (with PTO) that my mother bought in 1978 and then gave to me when she was diagnosed with terminal cancer about 6 years ago. At the time, the PTO version was supposed to be only available in Canada (according to the Troybilt site), but she got one. She and my stepdad were still keeping a garden after I left for college in 1976, but not one so big as needing the 8N or the Cub Farmall anymore. The old plow horse was sold along with all of the cattle when my step-grandfather got too old to be out amongst them (but you couldn't tell him that), so they didn't have her to work the garden with either. So, my mother bought the Troybilt 6HP Horse with hiller and furrower so my stepdad could still work the garden. The plow attachment had never been used until I did after I got it, mostly out of curiosity and while prepping a new garden plot. It had the 6 HP Tecumseh on it, cast iron block and that was probably one of the quietest air-cooled engines I've ever been around. Unfortunately, parts for it simply aren't available now, so I wound up repowering it with one of Harbor Freight's Predator engines, which looks very much like a Briggs & Stratton. That thing is even quieter, and a lot stronger than I remember the Tecumseh being. Probably the overhead valve thing, dunno. I didn't have to do a thing to the shaft or any shims or anything. It bolted right on, the pulley (which I should have replaced) fit like a glove, and it went on so fast I kept thinking I'd missed something. I still need to refit the throttle cable, but it really isn't that big a deal because the Predator came with a throttle lever on it as well as a cut-off switch, and best of all, a fuel cut-off valve. When I get ready to store it for the winter, I just shut the fuel valve off before I pull it into the shop, and let it run out of fuel to drain the carb and keep the ethanol from screwing it up. I liked that so much, I've added fuel cut-offs to ALL of my small engines. I haven't replaced a carburetor in a long time now. The Predator is a good bit lighter than the Tecumseh too, cast aluminum versus cast iron, etc. That really didn't seem to affect the performance much, albeit it's a little heavier in transport holding the tines off the ground. Not a problem if I put the depth gauge all the way down, though. If anything, it makes it work better in the clay and rocks I have here versus the nice soil I grew up on. I've used it to clean up and flatten a few places in my yard but getting grass to grow back on this deadpan makes me hesitate to do that anymore. Now, I use it when me and the missus build a new flower bed and need to mangle small roots and chew up the clay some and mix in chips and stuff to loosen it up.
I need to give the Horse a complete overhaul/restoration. Tranny sounds/feels good, no noise from the PTO, but axle and PTO are both leaking, so I figure seals and fresh dif grease should do the trick. It could use a set of tines as well. I would LOVE to sandblast and powder coat it, which would be a better paint job than it had originally, but I'm not sure if I want it out of service that long. Most of the decals have peeled off because it was left sitting in a lean-to next to our storage shed, (and then under my deck for about 6 years) so not really inside any part of it's life. I found out the decals are still available from Troybilt, though. I put tubes in the original tires, and it's working like a champ. It has the original turf tires on it, but I'm thinking bar-lug if I restore it. My folks' place had really nice sandy soil, easy to work, and the turfies were fine for that, but this sticky clay fills them up QUICK.
I managed to get the old Tecumseh to start when I first got it up here from the home farm, but it was using more oil than fuel because the piston rings are stuck. It was blowing oil out the muffler, but still, it ran (poorly). The blow-by was so bad it started pushing oil through the PCV into the breather housing. Needless to say, I knew it was done-for without a major overhaul. Those were TOUGH engines. I tried to find a new carb for it because it STILL had some sludge in the fuel tank which says it just got parked with a full tank and never used again. In the mean time, I just took it off, disassembled, soaked it in some Seafoam for a couple weeks. Put it back together, and it fired up. I was impressed that it wasn't completely seized up. I was going to break it down and see if I could salvage it, but HF had a sale on the 6.5 HP Predators for $100 about the same time I was researching parts for a 50-year-old Tecumseh. Nearly every major component in the engine shows up as "No Longer Available" on the Tecumseh site. That made the decision to repower a no-brainer. I was going to wind up spending that much in parts to resuscitate the old Tecumseh, and still have no guarantee it would run any better. I wanted to keep it original through and through, but it just wasn't in the cards.
I still have EVERY piece of the original documentation on that thing, Owner's manual, all the marketing pamphlets, bill of sale, even the freight bill where she signed for it when it was delivered. She even put a copy of the cancelled check in the file with it. Now I know why I'm such a packrat. I added the receipt for the Predator engine to the file.