I've got a problem that goes back to last summer and has come back to my garage floor yesterday. This John Deere G110 deck loves to throw it's belt, but not consistent. I have changed the belt and idler pulleys. Unit will run fine for two to three weeks and then starts throwing the belt. Will do it multiple times. Neighbor brings it over and I check it out, can't find cause, send it back and it will work fine for another two to three weeks, then repeat the problem. I have tested it myself, have thrown the belt, but I can't find a cause. Happens most often when engaging the PTO, but will also jump off during operation. I have checked the spindle pulleys, looked for sticks or twigs on the deck, tensioner spring looks good, and jackshafts look to be running true. Unit is about seven years old and I have done all the service on it. he brought it over yesterday and said " do what you need to do, so we don't have the problem this summer". I don't want to throw parts at it, but I know that I must be missing something, probably something small or stupid. Anyone have any suggestions as what to look for or had this problem come up. I don't have much hair left, but if I can't figure this one out, I won't have any.
I am going to make some assumptions here. I am assuming the the belt is running toward the top of the idler pulley, when mowing. I suspect it is either shock loading the belt, and causing a bounce throwing it off the idler pulley. PTO engagement or maybe deck getting bogged down causing a slack situation and bouncing the belt off the idler tension pulley.
Had an issue with a new MTD rider with the problem a few years ago, that had to do with the deck mowing too low, and putting too much of an angle on the belt, causing it to flip off the idler pulley.
I have thought the same thing. Do you think it is possible that the low end travel point is set too low? If so does anyone know what the lowest height measurement is for John Deere units? That is something I have never checked or adjusted. It may have had this deck off more times than I can count (have to install blow each winter) and I adjust levelness each spring. Maybe I have it way too far out of adjustment and have too start over. What are your thoughts?
Could be out of adjustment. Could be getting slack in the connection points causing slop, IE allowing back of deck to ride up throw the belt. Mowing at a higher setting may eliminate the problem.
You could be right. I guess the only thing I can do is to attach the deck to the tractor and set the deck height higher. Maybe one of the JD guys can give me a starting point to set the height. Do you have any guesses where to start? Only trouble with this idea is that I won't know if it will solve the problem for six weeks.
With the PTO engaged, kill the engine and look where the belt is riding in the idler pulley at different cutting heights . A worn idler pivot can be the culprit allowing misalignment .
I've done it with my Murray while running and elevated on the saw horses ( rear wheels ) and tail gate ( front wheels ) but I don't recommend that for the faint of heart .
