Snow Attachments Shear pin dilema

[ScottyChip]

Hi Ray, I have the same blower and I haven't broken a fan shear pin in over a couple of years. I also have a gravel driveway about 400 feet long, and I clear the snow out of the horse paddock when it gets to deep for him to move around. The times when I have broken the fan shear, fist sized rock gets past the auger, it's amazing how fast the blower comes to a stop when it gets jammed, and I sucked up a stack of sales flyers buried in the snow at the end of the drive, started to shred but then to much to handle, pop.
I have to agree Winmac, sounds like you may have a problem with the blower, can you rotate the augers easily by hand? Mine rotates quite easily by hand, is the gear box full of oil/grease? Do you start the blower at low rpm and the go to operating speed? This was my mistake first when I got my blower, but I only sheared auger pins, not the fan. You say you operate at 2100 rpm, for 540 on the PTO? I have to operate at 2600 with my B7510 to get 540 at the PTO, could it be it is operating to slow? Do you grease the PTO shaft, universals, augers and pillow bearings at the end of the auger shaft regularly? I grease my augers after I finish blowing snow, while the auger shaft is warm and easier to get grease in. Finally, I just purchased my replacement fan bolts at Princess Auto here in Canada, they seem to work fine.
I wish you all the best in solving this problem.

 

[B7500Ray]

Thanks Everyone for your help.I think my issue was the bolts I used, the unthreaded portion of the bolt was too short and were shearing within the threaded portion.
I blew out some of my paths yesterday, they were drifted in pretty good and I had no problems at all.Thanks Again,Ray