Thanks for the replies. I did get it replaced. I think the instructions in the manual are impossible to execute. They say to work the belt down over the blade drive clutch, and then work it off the transmission pully over the transmission cooler fan. But the belt is just not long enough to do this. What does work is to work the belt up above the crankshaft pulley to where it is just around the crankshaft itself. Then you have enough slack to work the belt up and off the transmission pulley. From there, removal is easy. It is made easier by taking off the belt retainer bracket that is around the crankshaft pulley, another tidbit that is not mentioned in the manual. Maybe this post will help others who might run into the same issues.

Maybe you will need to support the frame and loosen the trans on that side.

FWIW, to me, that's a classic signal that the old belt has stretched and time for a new one. However, as pointed out above, is it OEM, as some of these things are not integral numbers, but have fractions added on. e.g. 80.5" rather than 80" If your new one is not OEM, that could be the answer. Also, as pointed out above, check linkages, routing, are idler pulleys free to spin, spring, binding, etc. Said another way, if you needed a 80.5" and your neighbor got an 81" or the generic cross reference took them there..... Don't understand "bucks you off?" It is a manual trans and if the rpm's are up and you "pop" the clutch, it's going to jump. Again, as stated, check for free travel on the clutch/brake verifying smooth operation and spring movement. I've attached a link to a Belt Cross Reference giving the length and width by part number. Using that, if you want to go aftermarket, you'll at least have the right size. Also, havinig the proper length, but wrong width can also lead to excitement. Good Luck, Ev Here is a link that might be useful: Belt cross reference

Tensioner pivot pin maybe freezing up spring can't overcome that freezup if belt squeal. Maybe bearing sqeal take deck out from under machine check for bearing bad at double pulley they have most load and fail more often more than not I replace double pulley and bearing two snap rings bearing spin in pulley change size to to large. check spindle bearing at this time seal bearing have common life of good 3 years meaning in 4th or 5th year multi bearing application 1 or 2 could fail. Is more important find change that occured then fix be easy.