Riding mower dropping belt

whynot162 · May 9, 2015

I have not found this issue in my searching, so maybe someone can help me. I have a John Deere 102 riding mower. It has been an ok mower But the last few times I have used it, the belt is comming off of the pulley on the engine, when disengaging the mower. Runs fine, and the pulleys on the deck seem to be ok. the belt guide at the engine is on the mower deck side, and catches the belt, but it is always off and down under the pully. The belt seems tight when engaed, so I am at a loss of what else to check.
This mower has the 2 blade 42" deck.

Thanks
Doug

davesl708 · May 9, 2015

How old is the belt? Could it have worn thin and stretched to the point where it falls passed the guides?

bigtiller · May 9, 2015

Did you loose the belt tensioning spring?

whynot162 · May 9, 2015

I will look, that is the one on the deck? I thought that was for tension when it was engaged to mow. I did not look at it, so I do not remember if it is there. I will check it after work

Danald · May 9, 2015

I had that happen several times on my old 140. It ended up being a bad spindle bearing. It would seize up at certain times and throw the belt

CobyRupert · May 9, 2015

Check the bearings by grabbing the pulley or the blades, with no belt tension and see if the shaft it mounts on rattles/move in its housing.

beenthere · May 9, 2015

bigtiller said:
Did you loose the belt tensioning spring?

Meaning "lose" as in lost?

whynot162 · May 9, 2015

I have checked the blades and bearings, and they did move a little, but not much. And it only happens when turning the mower deck off. Not when it is running.