Post Hole Digger Shear Bolt question

[nspec]

Just bought a used Woods posthole digger. The bolts which are in the holes where the shear bolts should be are not correct. So, I go to put the proper sized shear bolts in the holes (according to the owner's manual) and the shear bolts as indicated in the book are significantly smaller than the holes on the unit. Is this right? I really can't imagine the previous owner enlarged the holes. Are the shear bolts supposed to fit snug in the hole or should they be loose. What we're talking here is a shear bolt a couple of bolt sizes smaller than the hole. Just doesn't seem right to me.

The next question is then, if it's NOT right, what should I do? Bigger shear bolt? Will I run the risk of hurting something if I use a bigger bolt? Should I just run the smaller bolt?

Sort of at a loss on this one, so any help would be greatly appreciated.

 

[CharlieTR]

There has been several discussions about shear bolts here, but I never heard about size of the hole being off. I only have two implements with shear bolts and they are both a perfect snug fit. Often people disagree on grade of the bolt. I use grade 5 bolts on post hole digger and shredder. Shedder has a very lary stump jumper.

If Woods help desk will not help you I would get bolts that fit,
Maybe grade 2 first. My PHD bolt takes a 9/16 wrench, not sure of the size of hole.

 

[Jeepnford]

When I used a Danuser auger it took either a 5/16 or 3/8 bolt (grade 5) and they worked fine. I sheared a few in tree roots and never did any damage to the auger. If they're too snug when they shear they usually bend and could be a challenge to remove.

 

[nebraskasparks]

I've done the same...sheared bolts off...put same size back in grade 5. That's what they're there for.

Maybe previous owner put in bolt that didn't shear well and had to drill the holes out and start over so to speak...I know a neighbor that did that!

 

[Ken45101]

That would be my thought, that the previous owner got tired of replacing shear bolts and drilled it out for a larger bolt

I would stick with what is specified. Start the auger slowly and I doubt that an enlarged hole will hurt.

Ken

 

[MMagis]

An enlarged hole certainly will cause the bolt to shear permaturely, and will cause excess play in the auger. The bolt needs to match the hole. Any chance that part of the manual is referring to a different model? Either way, shear bolts specs, IN MY OPINION, aren't rocket science like some would lead you to believe. I borrowed a PHD once that had grade 8 bolt as a shear bolt. Worst thing that happened was the tractor bogged down. If you're really worried, call Woods.

 

[nspec]

Thanks guys. Turns out to be operator error. The spare shear bolts he gave me were not what the book specifies. What the book specifies fits the hole. Problem solved, appreciate the help!