Will the drive belt on a 62d slip after 150 hrs?
I recently pulled the blades on my 62d to sharpen and balance. Things went well and the deck seemed to be working just fine. Toward the end of my first mowing session (about an hour in on the sharpened blades) I hit a tree root that was sticking up above grade. It wasn't a violent hit, but it definitely ground the root a bit. At first there was no problem as I drove away. But within a minute, there was a short burst of metal on metal noise.. sounded like the blade hitting the deck housing... Then fine for 30 seconds, bl then another burst. This happened three more times before I shut the mower down to inspect.
When I flipped the deck up, I observed the three blades had change orientation with each other. I.e when I installed the blades after sharpening, I had the middle blade positioned out of phase with the outer blades to maximize spacing between blade tips. The blades were now almost all lined up. It appears the middle blade and the right most blade (closest to discharge chute) were making contact.
I figured that the belt was slipping and sure enough, I was able to hold the middle blade in position and rotate the other two blades by hand. Should that happen with the deck off the mower? Or should the belt be tight enough to hold blades fixed? As I said, I might have 150 hours on the belt over the last 5 years, which seems young. Any other thoughts on what might be happening here?