Recommended Drive Belt Is Too Loose 

I know now though not to buy drive belts off the internet because they sell deck belts as drive belts so now I'm stuck with 2 deck belts i didn't need.

I have the same problem with my John Deere D110. I put a new drive belt on which lasted for a short time but is slipping again. Both times I managed to get belt dressing on which helped for a while which told me the belt was slipping. I'm considering changing from an 89 inch belt to an 88 inch since the tensioner is bottomed out. I imagine a dried out belt could contibute to this but if the tensioner has no more room to move.... Yes it is very difficult to get the belt on this off the rear pulley.

Belt diagram is correct. I too had the same problem when installed a new belt (130969) for my craftsman T3500. I've looked to see if there was a way to adjust the tension but nothing. Did you figure it out? Only option I see is running a shorter belt.

no issues good belt sp far

We replaced our drive belt and it wasnt too bad. Still driveable but struggled up steep hills so we knew it was time to replace. When the identical new belt went on it was so loose the machine would move at all. They were both exactly the same belt so why!!!? Only way we fixed it was we had to modify the brake spring to make it pull the tensioner tighter. Its the large spring on the sidewall running along the belt. Just clipped a few rings off the end and made a new loop. 2007 LTH1842 (92.5" belt) What I dont get is, is this isnt really a drive belt?...its a fan belt. I dont understand why the belt is running when sitting there just with the brake off. But when you go back and forth the belt just keeps spinning at same speed. Odd.

Wrong side of the stationary pulley i think

Grass builds up behind the brake and dosnt let it return all of the way leaving slack in the belt

so what was the fix???