B2789 snowblower shear bolts

[Rabuf]

"but he seems to be saying he's got two different part numbers for the auger shears, and two different part numbers for the impeller shear."

Exactly. I've got a shear on the driveline and a shear on the driveshaft and the manual states two different bolts for each location.
Look at the bolt for the driveline in the photos. Page 23 states to use a M10 and gives a part number. Page 35 gives a different part number for the bolt (#9 in the exploded view) and when I ordered under that part number, I received an M6. It's the same case for the drive shaft shear bolt. You'll see on page 23 it calls for a 5/16" NC x 1 3/4" gr. 5 and yet on page 32, the driveshaft shearbolt is #37 and calls for a 1/4 " NC x 1 3/4" grade 5. (The difference on the driveshaft bolt isn't as radical as the difference in bolts for the driveline.)

I know this is an old post but for the benefit of others that may be looking for the answer... I have the exact same model blower and the same problem with the manual. The bolts identified on page 23 are too large. I found the specs in the rear of the manual on pages 32 and 35 to be correct, or more specifically:

Product ID: 77700-00228
BOLT M6x40 GR. 8.8 AND NUT

Product ID: 77700-00206
BOLT, SHEAR 1/4x1 3/4 G5 w/NUT

Hope that helps...