Thanks for all the advice. The tiller was working fine before the belt broke. Started easily. Now new belt and it doesn't. A sheared pin sounds serious. Possible it could of sheared at the moment the belt broke? I suppose that might of happened. But as I recall after the belt broke I believe we started it a time or two to try different things to see what was wrong. How annoying. I'm even thinking about buying one of those hand tillers or just string trimming the tall weeds in the corners of the vegetable garden. Or even hoeing. Might end up being less work and less frustration!

If replacing the rubber faced wheel, there are 4 bolts to remove, and the disc, then install the new wheel and bolt it together. To replace the aluminum disc, which is on the crankshaft, you will probably have to loosen the engine mounting bolts, raise the engine up on blocks of wood, then get under the back end, and using a hammer and a bar, spin the disc off the piece that is held onto the crankshaft.. It is standard right-hand thread, so you would turn it to the left to remove it. If you do not remove the mounting collar with it, just spin the disc off and spin the other one on, and tighten it up with the same tools you loosened it with. Some folks say to remove the engine, but it isn't necessary. A pair of octopus arms are helpful, but you only get those from many years of mechanical and auto body work! NOTE: The correct spacing of the disc is: From the face of the disc to the smooth, engine mounting flange face is 3 7/8 inches. Some say--to the top of the engine mounting area at the big hole--but, it amounts to the same measurement, and is easier to do the way i do it. For this work, it is best to jack the mower up high, and set it on jack stands at the rear. Block the front wheels. use a long 3/8 inch extension, socket and ratchet to get to the engine mtg. bolts!

Well, i bought my belts at a local store that has or will order new matching belts for tillers, or anything else. They sell lots of parts, and will order anything i need! Check in your area--there must be someplace where you can buy parts, belts, etc. But not Home Depot, Lowes, or any place like that! And, automotive belts will not last as long as the kind used in mowers and tillers. As for replacing the double belts, its a bit tricky, but not that tricky! Here's how to do it: Move the clutch handle to loosen tension on the belts. Then, first thing, take forward belt off lower front pulley, and rear belt off rear upper and lower pulleys, and slip it out. Then remove front belt. To install the new belts: Hang front belt over the front upper pulley, but not the lower one. Slip the rear belt in under the front and into the rear lower pulley, then install it in the top rear pulley. Then slip the front belt over the lower front pulley, and its done. you may have to adjust the sliding block, but that isn't too hard to do. It might not let the handle stay in position if its out of adjustment. HTH: Rusty Jones

Re tomplum: I went out to the tool shed (with my glasses this time) and cleaned the window off the clock. It actually reads 155.8 hours. I didn't see the decimal point. That can't be right, though, since in the 8 years I've owned the mower I've used it for about 40 weeks a year, and it takes at least 2 hours per week to mow the lawn. (I was trying to maintain a fescue/bermuda winter/summer lawn. I've given up on the fescue and the bermuda will require more frequent mowing.) So the actual number of hours on the machine is at least 640. Probably a little more, but considerably less than 1550. When the mower wouldn't move after I changed the belt I shut it off immediately. It wasn't on for more than 15 seconds. I may have ruined the belt, but I don't understand how it can run smoothly in reverse if that's the case, but then I don't understand a lot of things. The upper belt looked like new, while the lower belt was cracked with sections missing. That's why I thought changing the belt would solve the problem. I bought a new upper drive belt and still have it, and if need be I'll put it on. The idler on the upper belt section turned smoothly and the spring is stout. Re mownie: I don't feel competent enough to tear into a transaxle. I was dreading changing the upper drive belt, since doing some searching about the job it was obvious that is was not a piece of cake. While there is a good deal of satisfaction from doing things myself, there is a limit to what I'll attempt. I've made an appointment with a local repair shop to look at the mower. I'll post a followup when I know more. Thank you both for the responses.