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!

Well, i have found, if something is in the way of some bolts that must come out-why-you'll have to remove that part first, then remove the other part! I removed an engine from a Troy-bilt tiller several years ago, and had to un-bolt a lot of stuff to get the engine off it. So, pull up a box, sit down, and eye-ball the whole mess, then you can see how to go about it! Really simple when you get into it! you might have to unbolt the reverse disc, and i know you'll have to take off the belts. One thing for certain: DO NOT UNDO THE BOLT WITH THE BIG SPRING BEHIND THE ENGINE ASSEMBLY!! YOU'LL THINK IT WOULD BE BETTER TO TRY TO FLY TO THE MOON, RATHER THAN PUT THAT PART BACK TOGETHER! This warning is even printed in large type in the manual that comes with the machine! I don't think a gear puller is necessary, but soak the pulleys with a good penetrating oil-not WD-40! you will find there is an allen bolt somewhere that holds them in place. If the engine slider posts are relatively free, and not rusted, it is possible to remove them and get the engine off that way! Measure how far they stick up out of their receptacles before removing them. Facilitates re-installation later. Then the casting that covers the belts and pulleys, and the engine, will come off as a unit!! HTH: Rustyj

My $161.95 early bird service for my JD GT275 turned into $375.81 service. see under posting "John Deere Lawn Tractor Buying Advice Needed: X300 or LA series" Thing of it is I've gotten just as good as life out of my Sears, oh well, The same thing happened when I bought a Lincoln Continental, T-birds were just as good but cost a good deal less. Now retired, I sold the Lincoln 2 weeks before I retired, because of the cost factor. Now, I use my wifes Avalon when I need a car, or just climb up into the Dodge Ram - yeh, it's a hemi. Like I've said I like HP. Enjoy, the cub, dragging that deck alittle at the shed door will do alot less damage than leaving it set out in the weather.

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.