I have an old round back tiller (model 18609) that I picked up earlier this year. It was working ok behind my 1054, some vibration but not too bad. I tilled about 4000 square feet of pig pasture and garden with it, then it started to shake and got very noisy, so I had to stop. I started taking it apart yesterday and found out that the roll pin that holds the worm gear in place on the input shaft had sheared off. I was trying to pull everything out through the front to repair it, but after fighting with the bearing race for about an hour, I just got out my old walk behind tiller and finished tilling with it. I will be busy planting for the rest of the day today and into tomorrow likely, then cutting grass (long weekend up here), so the tiller will be sitting till next weekend at least. I am wondering now though if I should just replace the existing roll pin or is there something I can do to make it stronger? I was thinking of maybe drilling it out and putting in a bigger diameter roll pin. I would appreciate any advice on this.