Shear Bolt vs Regular Bolt

[RickB]

The shear bolts on my snow blower have the groove, two of them I think.

So, is it safe to replace a Grade 2 shear bolt with a Grade 2 regular bolt?

The term shear bolt is terribly misunderstood. They come in all grades, with relief grooves or without. Every machine that uses shearbolts also has a specification and/or part number correct for that application. That spec may be grade 2,5,or 8 with or without relief grooves. There are metric shearbolts in 4, 8.8 & 10.9 hardnesses. Learn your machine's shearbolt requirement and buy the correct bolt wherever you choose.
The majority of shearbolts are common hardware of a particular size and hardness available from a variety of sources.

 

[boggen]

Geez, this is an old thread but exactly what I am going through now. My neighbor picked up some bolts for at TSC and they keep breaking. When I bought my rotary cutter the original bolt lasted a long time even with an inexperienced operator, myself. I am going to the JD dealership to find out about the right bolt which is a Grade 2 and ordering it through them.

many rotatory cutters, have a "slip clutch" on them. located between the PTO shaft that and the Gear box on the rotatory cutter. it most likely looks like a big metal wheel with springs or skid plates on it. it might be easier to figure out the slip clutch vs constantly relying on a sheer bolt.

 

[Gale Hawkins]

many rotatory cutters, have a "slip clutch" on them. located between the PTO shaft that and the Gear box on the rotatory cutter. it most likely looks like a big metal wheel with springs or skid plates on it. it might be easier to figure out the slip clutch vs constantly relying on a sheer bolt.

This old cutter was purchased by the late FIL sometime after buying the tractor in 1977 and it has a slip clutch which I love. I was working in some 3 years of over growth and did not realize it was slipping and had to replace the circles of clutch material. It was under $10 and not a hard job but setting the tension was trial and error since it was my first experience. Now if it goes to slipping cutting trees the size of my wrist I get it out of the load fast and let it recover. It is a 6' cutter and very heavy duty.

 

[MossRoad]

I hope Mike listened to Rob.... it was 12 years ago! :laughing:

Still good advice, though.

 

[MikePA]

I hope Mike listened to Rob.... it was 12 years ago! :laughing:

Still good advice, though.

I did!

Still have the same snow blower, too. :laughing:

 

[mrutkaus]

Same sort of wondering as above. New to me Woods Snowblower sb74-2.

Looking on line it appears that Woods has replaced an original un marked or un mark-mentioned-in-parts-list 1", 5/16" NC with a GRADE 8 same size bolt. So I don't know. Since they have 'updated' it with a harder bolt I'm assuming there is a reason. Perhaps the harder bolt is more apt to fracture?

Mike

 

[Rford]

Old thread I know, but I've got a Bush Hog Rhino that snaps those ungraded TSC 1/2 bolts like they were pretzels. Sometimes just a clump of grass will shear them and if the blade hits nearly anything they snap. I've been tempted to use grade 5 where a know its a pretty clean mow but, since I've got the bolt changing down to a science, I'm faster than the dad on "A Christmas Story" changing spare tires.

I was reading another post and it said that the problem might be not running the RPMs high enough. A slower RPM causes more shearing. That might be my problem, I'm probably on the slow side and maybe not even 1500 RPMS a lot. The post said when he went from 1500 to 2500 the shearing stopped. I'd never run mine up that high, but I might go up a bit and see if it helps.

 

[jwalk2c]

Old thread I know, but I've got a Bush Hog Rhino that snaps those ungraded TSC 1/2 bolts like they were pretzels. Sometimes just a clump of grass will shear them and if the blade hits nearly anything they snap. I've been tempted to use grade 5 where a know its a pretty clean mow but, since I've got the bolt changing down to a science, I'm faster than the dad on "A Christmas Story" changing spare tires.

I was reading another post and it said that the problem might be not running the RPMs high enough. A slower RPM causes more shearing. That might be my problem, I'm probably on the slow side and maybe not even 1500 RPMS a lot. The post said when he went from 1500 to 2500 the shearing stopped. I'd never run mine up that high, but I might go up a bit and see if it helps.

The problem I have with those TSC sheer bolts that come in the pack of 6 or so is they are not shearing no matter what RPM, or what I hit. I bought a slip clutch last year to ease my worries. I am running the sheer bolts on a 5 ft TSC bush hog and a FORD 1520 23 hp. I can hit a solid object that almost stalls the engine. The sheer bolts have to be drove out as they are bent but have yet to sheer off. Maybe I should try another pack? Strange but this is my luck always.
Thanks Johnny Walker

 

[kenmac]

I have no problems with the non graded bolts I but from HD, Lowes, etc

 

[topbuilder]

Old thread I know, but I've got a Bush Hog Rhino that snaps those ungraded TSC 1/2 bolts like they were pretzels. Sometimes just a clump of grass will shear them and if the blade hits nearly anything they snap. I've been tempted to use grade 5 where a know its a pretty clean mow but, since I've got the bolt changing down to a science, I'm faster than the dad on "A Christmas Story" changing spare tires.

I was reading another post and it said that the problem might be not running the RPMs high enough. A slower RPM causes more shearing. That might be my problem, I'm probably on the slow side and maybe not even 1500 RPMS a lot. The post said when he went from 1500 to 2500 the shearing stopped. I'd never run mine up that high, but I might go up a bit and see if it helps.

You should be running "PTO " rpms all the time with a brush cutter. It can wear on the clutch at too low a rpm as well.