G2742 Snowblower shear pins

[bill18163]

I have a Loftness three point hitch snowblower. There are three shear bolts in the machine. Two are in the machine itself and one is in the PTO shaft. The two in the machine are Grade 5(has three radial lines in the head of the bolt) and the one in the PTO shaft is a Grade 2(has no radial lines in the bolt head). There are no grooves cut in the bolts. I have never sheared the Grade 5's. The Grade 2 in the shaft has always gone first. Replaceing the sheared bolt is about 10 minutes work. Buy them by the pound at TSC. Just for reference sake if you see six radial lines on the head of a bolt it's a Grade 8(don't EVER use them for shear bolts). It takes 120,000 PSI to break a Grade 8, 85,000 PSI for a Grade 5 and 55,000 PSI for a Grade 2.

 

[irvingj]

Getting better! Drove the 2310 to a friend's house yesterday to clean up their driveway/parking area. Just bumped --once-- their stone wall & took out the shearpin I'd just replaced....

As it was a 1.8 mile drive to this house, I had the foresight (amazing, in & of itself, that!) to grab the spare shearpins, hammer, drift punch, & 1/2" wrench & socket and carry them with me. This time, it only took 3 minutes, as the center section of the sheared bolt just dropped out when I got the holes lined up. Lucky again, I think!

Guess I'll go today & pick up some grade 2s to have on hand until the factory pins are available...

 

[atgreene]

I posted to another thread about this, use an in-line slip clutch (adjusted apporpriately) and your use of shear pins will drop dramatically.

Her's one from TSC Tractor Supply Company - PTO Slip Clutch, 1 3/8 in x 1 3/8 in

Warning: Make sure you carefully check the length of your pto shaft after adding the slip clutch in-line. Had a friend add one and not shorten the shaft, when it bottomed out it drove the gearbox shaft through the gear box grenading the entire assembly.

 

[art]

I broke a $12 shear pin the first pass on a dirt driveway today. I'm glad it was the pin and not something else but does anyone know if there is something else I can use? $12 is a ripoff in my opinion when other manufacturers are 90% cheaper. I will keep using them if I need to but its going to be an expensive winter!

The one on the auger is $1.71 if that is the one you broke.

 

[chinawall]

Never heard of a $12.00 shear bolt! Get mine for less than a buck.

 

[art]

Should the shear bolts be torqued or just tightened?

they should be tightened not nessesary to have a specific torque so they do have some tensile strength.

You have to remember, everytime a bolt shears that it might be moving some metal from the shafts holes that it sets in. This also means the they very well might start shearing easier on there own as the holes get egged out!!!!

This means that if the shear bolt is to soft, it might shear more often,giving lower performance. Or if it is to hard that it might not shear until something else breaks.