Goofy Manifold

P.S. I am also having shear pin problems with my Pittsburg 240 brush hog. I have put three grade 2 bolts in there this weekend and I keep snapping them. Can I go to a grade 8 bolt without tearing up the hog, before snapping the bolt? And yes, I am using an ORC. Thanks again!---Rob

Considering how cheap grade 2 bolts are by the handfull at the hardware store... it seems its a no-brainer... Your machine though.

Soundguy

Over time, shearpin holes wear, so they are no longer a straight, constant diameter hole, but get deformed (wallowed out) towards the OD of the shaft, or the ID of the sleeve (U-Joint) you are pinning to the shaft. If you have wear like this, the shear pin is bent (deformed) as soon as you put a load on the driveline, and is more prone to shearing unnecessarily than if there is no wear in the pin hole.

This may be a factor on your machine.

You mention going from a Grade 2 bolt to a Grade 8. Have you tried a Grade 5?

I have had equipment with worn shearpin holes that made it useless, and have carefully drilled the hole 1 bolt size larger to square up the hole. Of course, then you would want to be sure to use only a Grade 2 bolt. I am not suggesting you do this, but if the pin hole on your machine is badly worn, it might be something to consider.

By installing a Grade 8 bolt you're going to override the whole reason for installing a shear bolt in there in the first place. Look for the reason they're shearing instead. Either you're trying to mow big rocks and logs, or your shaft bearings are failing, which is putting stress on the shear bolt.

Putting a grade 8 bolt in there is a sure way to turn your gear box into shrapnel.....