Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I have a new Honda HS928TCD blower.  Apparently a change was made in the past for the shear pins for the HS928 so now there are two types available, depending on the frame serial number. The older style pins have a P/N of  95701-06016-00 and the newer style is 92101-06016-0A. Since I have a bunch of the older style shear pins, I am wondering what the nature of the change was and if the older type of shear pins will work for the newer model.  If the old style is used on the new frame type, is there a danger to the gearcase because the shearing point is different?  See  http://www.boats.net/parts/search/Honda/Snow%20Blower/0/HS928%20WAS%20SNOW%20BLOWER%2C%20JPN%2C%20VIN%23%20SZAS-1100001%20TO%20SZAS-1129999/AUGER/parts.html for the illustrations.  Any ideas out there?

The spare spare shear pins that came with my new Honda 928 are hex head flange bolts.  On the cap, there is an "8" in a circle with an underline.  The nuts are self locking type.  I'll see how they compare to the new ones.

 

Left bolt is from my Honda dealer ($0.36) and Right bolt came with the blower.

The one on the right is the type that came with my blower too.  But I haven't taught them to play the piano yet.

Only Yamaha thing we have at our home is the piano.

Not an option fpor the Honda.  But does it blow snow too?  Would be nice to listen to a little Mozart while following the Yamaha  LOL.  Comment from Mr. Rubinew??

Is there such thing as a "metric" grading system for bolts that is different from a non-metric "grading system" for bolts.

Or is a grade "8" all there is.  I am not familiar with the grading system for bolts.  "8" sounds pretty hard (or strong) to me.

I would think that we would be looking for a softer bolt to protect our auger gear box.

There are grading systems for bolt strength in both SAE and metric. SAE are tested in PSI, metric in MPa.

Unmarked: minimum yield strength is 57,000 PSI, metric unmarked is 640 MPa. Minimum tensile strength for these are 74,000 psi or 800 MPa.

Unmarked bolts are untreated low or medium carbon steel. Grade 5 and metric 8.8 are medium carbon steel, heat treated and tempered. Grade 8 and metric 10.9 and 12.9 are heat treated and tempered alloy steel.

The higher the grade, the stronger the bolt. You want shear pins to be weak. They're supposed to break. The stronger they are, the more stress you apply to parts that are not designed for it.  Repeated stresses will cause failure.

Its easy for me to find unmarked metric bolts.  They are cheap too.  Based on the information outlined here I'm understanding that an unmarked metric bolt would be easier to shear than a bolt marked 8.8.   Does this logic seem misguided?  Sometimes ingorance carries a price.

Could be, misguided that is.  I have seen comments where the "unmarked" bolts are simply rejects from lots of higher grades that didn't meet specs.  If so, then they could be anything.  Dunno if this is so or not.  One would think that if it is, they would have to grind off the markings on the cap to make them unmarked,  unless they put those markings on after they make and test the bolts.  Or maybe they make the bolt stock first, test it before completing the bolt making process. and just make the stock that doesn't meet specs into unmarked bolts.

Underdog wrote:
Correct.