What grade shear bolt for subsoiler?

stevenf · Aug 25, 2006

I bought a Bison SVH-1 Subsoiler the thing weighs 220lbs and is a monster compared to the King Kutter model. It has a 25" X 1.25" parabolic shank on it and in looking at the specs is designed for a minimum 40hp tractor. I'm using a 90hp M9000 to pull it. I got it home last night and rigged my 3point up for it, It has a 3/4" #3 grade main bolt and is supposed to have a 5/8 #3 grade shear bolt but the one that was on it had no markings so we'll assume it was a grade #2 anyway as soon as it touched the ground, it sheared that bolt like it wasn't even there. Since I'm using a 90hp machine and the subsoiler appears to be built like a tank am I safe in going to a grade 5 or 8 for the shear bolt especially since its only a 5/8" bolt and the main bolt is 3/4". The bolt they had on it was subgrade but was the correct length as none of the threaded area was exposed to the shear area it was solid smooth 5/8" that it sheared.
Steve

stevenf · Aug 25, 2006

OK, I guess nobody has a Bison Subsoiler I bought a bag full of grade 5's and grade 8's I'll let ya'll know how it goes.
Steve

stevenf · Aug 26, 2006

Well grade 5 shear bolts and a grade 8 main bolt worked fine I just set my draft a little light and it worked out fine. I did shear both the original shear bolt and the main bolt but they were obviously chinese steel and the shear bolt wasn't even marked. I will say that with a single shank subsoiler does take a while to subsoil several acres but then my 7 shank chisel plow went right in without any nonsense. I still have to disc it out, fertilize and plant it but its looking great.
Steve

john_bud · Aug 27, 2006

Steven,

Yep, 90 hp and cheap China bolts go together like butter and a hot knife! Well, that and your hard as steel soil...

Glad to hear you got it working and that the subsoiler is tougher than the bolts.

jb

Nuru · Aug 27, 2006

Yep Glad you got it together. I use the KKutter variety for my less-manly 20 hp unit though. 220bs, wow, pretty heavty. BTW, how much did that cost?

stevenf · Aug 27, 2006

NURU, It was $440 for the subsoiler and $75 for frieght, I could a picked it up in North Texas but the fuel would have been more then $75 so they drop shipped it to my Kubota dealer thats 12 miles away and on my daily route.
My rock hard soil is right I turned over dirt clods as big as a VW beetle needless to say if we don't get some rain on the field discing is going to be a very unhappy chore.
Steve