shear bolt grades

   / shear bolt grades #1  

dass

Silver Member
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Aug 2, 2001
Messages
245
I sent a family member to the hardware store to get a few extra shear bolts for my snowblower. The manual calls for grade 2. They came back with 8.8 metric bolts. That's all they had in the size I needed but I thought 8.8 was equal to a grade 5. Who's right, here ?
 
   / shear bolt grades #2  
If you like your tractor an implements.. you should only use grade 2 shear bolts... Unles sthe manual specifically calls for somehting else.

If that hardware store only has grade 5.. shop elsewhere.. your tractor is to expensive to let a 50 cent bolt rip the rear end out of it..

Soundguy
 
   / shear bolt grades #3  
You are right, an 8.8 metric is equal to a grade 5 SAE. If your manual calls for grade 2 SAE then that's what you should use.

I have a tiller that calls for 8.8 shear bolts and it came with a package of 4 spares. I've had to use one spare so far (3 years).
 
   / shear bolt grades
  • Thread Starter
#4  
I might add that the original shear bolt had a triangle stamped on the head. In metric terms that must have been equal to a grade 2. It's the first one I've ever seen. Last winter I caught a rock and stalled the tractor, the bolt did not shear off ! The assembly was rusted tight. I cleaned it up and lubed everthing. The bottom line is ; make sure those parts are free to move or the shear bolt is useless. Same for a slip clutch. If the clutch packs are rusted or frozen they can't work.That's why you don't see slip clutches on snowblowers.
 
 
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