Grade 5 Shear Bolts

[dirtydeed]

I'm having some difficulty finding 5/16" x 2.5" grade 5 shear bolts (these are for PTO shaft on flail mower)...looked at TSC, Amazon and McMaster Carr without any luck. Anyone else have a supplier?

I see some on amazon that mention that they are used for Kubota snow blowers...but I think that they are Grade 2 for the auger drives...

 

[Old Machinist]

Lowes lists a fine thread grade 5 in that length.

https://www.lowes.com/pd/Hillman-5-16-in-x-2-1-2-in-Zinc-Plated-Fine-Thread-Hex-Bolt-2-Count/3012776

 

[dirtydeed]

wasn't sure if I needed an actual shear bolt or if any grade 5 bolt would do.

 

[Old Machinist]

If it calls for grade 5 and you find a grade 5 bolt that fits it should be okay. It doesn't have to be called a shear bolt. The hardness and fit is what matters.

 

[RCW]

If it calls for grade 5 and you find a grade 5 bolt that fits it should be okay. It doesn't have to be called a shear bolt. The hardness and fit is what matters.

I would never disagree with a member whose moniker is "Old Machinist."

I'd go with a straight Grade 5 as he suggests.

Just my snowblower model BX2750D, but they're grooved OEM shear bolts for mine.

Look like a grade 8 (right) for the impellor, and two grade 2 or 5 for the auger.

Not sure that's what you want for your application.

 

[Magicman]

You are risking a u-joint using a grade 5. My cutter uses a grade 2.

 

[mcfarmall]

You are risking a u-joint using a grade 5. My cutter uses a grade 2.

Minimal risk if the owners manual says Grade 5.