Help Broken Shear Pin

[Bob77064]

Ran the bush hog ( mdern ag ) 5' cutter for a short time. The shear pin broke. The top of the bolt ( pin ) says 307A and JG. IS this a common part and how hard is it to change?

 

[phiferpharm]

I'm guessing this is the Bolt that attaches your drive shaft to the gear box on top of your bush hog. I use low grade bolts from the hardware store and have had no problems with them. I guess I will pop one every couple of hours of use, especially when I'm in a new area of the property. Takes maybe 5 minutes to change.

 

[strum456]

It sounds like your bolt is metric, based on the letters on the head. A standard bolt will have lines. 3 lines = grade5 5 lines= grade 8 (just to name a couple). Anyway, get the correct size bolt and you should be good to go. Make sure the bolt isn't threaded where it goes through the yoke and shaft or it will wear the hole goose egg shaped.

 

[tcreeley]

Softer bolt has fewer lines. Softest bolts have no lines.

 

[strum456]

Count your lines, add two and that's the hardness grade. This only applies to standard bolts. Metric will have a number, like 8.8.

 

[Bob77064]

Thanks for the help everyone.

 

[Mark Page]

A large pin punch/drift will make it easy to drive the old bolt out. If need be you can drill it out, but should be a last resort.

 

[wcampbell47]

Reading this makes me want a shredder with a slip clutch!

 

[Bob77064]

Thanks Mark & WC, this makes me wonder if I should have gotten a model with a slip clutch. But I have been told me that if you don't use the cutter with the slip clutch enough that the slip clutch can rust together.

 

[wcampbell47]

Thanks Mark & WC, this makes me wonder if I should have gotten a model with a slip clutch. But I have been told me that if you don't use the cutter with the slip clutch enough that the slip clutch can rust together.

Recently read a thread on servicing the slip clutch at the beginning of the season to cure just that ill. Something like loosen all the bolts then from the tractor engage the pto in order to break it loose. Need to find and re-read as I need to service the slip clutch on my tiller.