# Shear pins - replace with hardened bolts?



## hobkirk

I ask my question with trepidation. I ran my own VW/Audi/Porsche repair shop for 15 years, although I was never a mechanic. I.e., I appreciate good engineering. 

In 10-15 hours of operation, 90% clearing driveways and walkways, I have had to replace a lot of shear pins:

*Maybe 12-16 shear pins on the auger*s (only 2 of which were caused by objects I could discover)
None on the two collar assemblies that the auger shear pins bolt into. 
*2 on the left drive wheel*
*1 on the impeller *(subject of another post) - and I used the special and unique Honda bolt
None of the front of the impeller shaft (at the auger end)

Why? 

My local dealer says Honda shear pins do seem to need to be replaced more often than other brands, although he's primarily Honda. 
*Is there something wrong with my workmanship or my machine?* The "collar" on my R (?) is slightly loose - it does not lock rigidly to the shaft, there is some play. But I think I break shear pins on the R and L about equally. Whenever I go into the bucket, I verify that the nuts on all the pins are tight.
*Any suggestions on where to buy them and save a little money?*

Solution?

Use 8.8 grade bolts? Or stainless (I've never checked their specs.)
Just keep buying more?

Thanks


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## skutflut

Do not use hardened bolts. 

Not sure why you are breaking so many, but if you go to a harder bolt, your gear box will become the breaking point. Not sure how much those cost, but being honda, I would expect in the hundreds, plus a lot more time repairing it. 

A few other members have mentioned that Hondas are breaking lots of bolts. Perhaps you should contact Honda customer service and ask if they have an upgraded bolt part number that would last. Is it possible you are over tightening the bolts which seem to be a bit soft anyway, and possibly partly twisting the right from the get go?

You might also send a PM to [email protected] on the board here, and see if he can shed any light.


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## Marlow

Have you got side skid shoes on your snowblower? I broke several shear bolts before I installed my heavy duty skid shoes, and haven't broke any since. And if you do have side skid shoes, then you likely need to adjust them higher, as clearly your auger is biting too low causing it to strike the ground and bust shear bolts. I bet if you look at your auger, you'll see worn "teeth" which would indicate you have it set too low.


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## dhazelton

"2 of which were caused by objects I could discover" That would leave the things you didn't discover. Are you hitting concrete heaves in the sidewalk or is there a steep driveway entrance (my augers protest when I get to the part of my drive where it meets the road as they paved it and left a huge lip I have to watch out for. I agree you should not torque them down hard and that you are probably starting to preload them for failure if you are.

Breaking the pins on the drive wheels should not happen - they aren't shear pins to my knowledge.


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## Vermont007

They're called "shear" pins for a reason. Their supposed to be sacrificed in lieu of parts that are more expensive.

Replace the cheap shear pins with hardened unbreakable bolts and you'll defeat the purpose; but you'll learn an expensive lesson.

It would probably be worth your while to ascertain the nature of the debris that is left on your driveway or walkway and remove it at the beginning of the season, and you'll cease having so many being sheared off.


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## hobkirk

Marlow said:


> Have you got side skid shoes on your snowblower? I broke several shear bolts before I installed my heavy duty skid shoes, and haven't broke any since. And if you do have side skid shoes, then you likely need to adjust them higher, as clearly your auger is biting too low causing it to strike the ground and bust shear bolts. I bet if you look at your auger, you'll see worn "teeth" which would indicate you have it set too low.


*Excellent answer!* I have NOT bought skid shoes yet and the machine does not have them already (I bought it used this summer). The scraping plate (?) appears to be straight and in good condition. Obviously this might not be the same for me, but it fits well. 

*Skid plates *- Am I correct that my options are:

*Steel brackets that mount behind the bucket *(I hefted one at the Honda dealer today - thick steel!) - I am confused about these - do they work as well as side plates? It seems like they would be fiddly to setup.
*Steel side brackets that mount on the side* (some can be flipped when the bottom "shoe" has worn through)
*Poly or HMWV (?) side brackets* - these are what I was planning to get, although I have not figured out where is a good place to buy them (or even if there is a preferable brand).


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## JLawrence08648

It's a long shot but maybe you have to much resistance in the auger and it's struggling. So in warmer weather I'd go back to basics, the beginnings, and take the auger assembly apart and replace all the oils and greases with the equivalent synthetic, less resistance, rolls better, water resistant.

When it's apart, maybe the side and impeller bearings have too much resistance. Maybe the auger shaft is rusted so sand it down and grease the whole shaft with a synthetic tube grease.

If you do this at least you have eliminated a potential and improved the machine.


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## dhazelton

I used Ariens brand poly skid shoes from Home Depot on my Honda which only had rear skids (MUCH better with side skids to keep the front and augers up out of the pavement). People have made them out of thick cutting boards. I toyed with the idea of using oak from a pallet which I bet would hold up fine. Your scraper bar should NOT be on the pavement, it should be about a 1/4 inch higher than the pavement. Put a couple of paint sticks under each side of the rear of the bucket then drop your skids down to the ground and that is the right height. If you have gravel to go over put a couple more sticks under the rear to lift it 1/2 inch and drop your skids to the ground at that height and you shouldn't be spitting too much gravel.


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## Marlow

My machine only had the rear skid shoes when I first got it. Even when I adjusted these higher, I was still biting pavement due to small humps in my driveway. Now I have the rears AND side skids installed and no issues at all. The snowblower glides along more freely as well without getting "caught" so much in the pavement. 

My theory is that there is a bit of flex in the bucket going over the humps, and the side skids are needed to prevent the auger from going to low when that happens. Several people on here have noted that they haven't sheared near as many bolts after side skid shoe install.


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## orangputeh

dhazelton said:


> "2 of which were caused by objects I could discover" That would leave the things you didn't discover. Are you hitting concrete heaves in the sidewalk or is there a steep driveway entrance (my augers protest when I get to the part of my drive where it meets the road as they paved it and left a huge lip I have to watch out for. I agree you should not torque them down hard and that you are probably starting to preload them for failure if you are.
> 
> Breaking the pins on the drive wheels should not happen - they aren't shear pins to my knowledge.


the pins on Honda drive wheels ARE shear pins. I would rather break that $3 pin than spend hundreds on internal damage.

In the last 3-4 years I have only broke ONE shear pin. Either the augers are hitting the ground because of improper shoe adjustment or the operator is trying to cut thru ICE berms or something else.

Shear pins are worth their weight in gold IMHO. They will save you hundreds of dollars in costly repairs in the long run.

NEVER use hardware bolts. Some people say you can use a small brass bolt since they are soft and break easy but I am not sure I want to gamble with my $3000 blower on that info unless someone from Honda can back that up.

Stock up on all your shear bolts when you can. Maybe 2-3 extra of each kind. Neighbors will love you in a pinch. And your wallet will thank you longterm.


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## RIT333

How about the guy yesterday that welding his impeller or auger to the shaft because he was having trouble getting out the broken sheer pin ? He doesn't know what trouble really is...until he hits a newspaper in his driveway with his welded "sheer pin".


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## dhazelton

How do you get ANY traction if the drive wheel is held with a shear pin? What is the part number, because I can't find reference to one and if I shouldn't use a regular linch pin if one breaks I'd like to have the correct part.


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## Marlow

dhazelton said:


> How do you get ANY traction if the drive wheel is held with a shear pin? What is the part number, because I can't find reference to one and if I shouldn't use a regular linch pin if one breaks I'd like to have the correct part.


I can't see it being a shear pin. When the tracks lose traction, they simply just keep spinning. There is nothing to break! Actually, a freely spinning track that has lost traction won't feel as much stress as one that has it's traction. For for there to actually be a shear pin in there? Don't make sense, as you are right the stress of actually properly having traction would cause it to bust.


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## dadnjesse

I bought a brand new HSS928 last year and broke sheer pins every time I used it, I got so frustrated I sold it and bought another new HSS1332 this year with the auger protection and have not had a single problem, I feel your frustration I lost a lot of money doing this, I have had many snowblowers over the years and never broke so many sheer pins in my life.


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## hobkirk

Marlow said:


> I can't see it being a shear pin. When the tracks lose traction, they simply just keep spinning. There is nothing to break! Actually, a freely spinning track that has lost traction won't feel as much stress as one that has it's traction. For for there to actually be a shear pin in there? Don't make sense, as you are right the stress of actually properly having traction would cause it to bust.





dhazelton said:


> How do you get ANY traction if the drive wheel is held with a shear pin? What is the part number, because I can't find reference to one and if I shouldn't use a regular linch pin if one breaks I'd like to have the correct part.


*The Honda part # is 90701-732-000*, it is about 5 mm in diameter and maybe 40 mm long, held in place by a clevis or cotter pin. One was missing when I bought the machine, and I have had to replace two since. 

Maybe the pin isn't breaking? It could be the retaining clevis/cotter pin (I think I used clevis twice, cotter once). 
the hole in the tractor wheel is elongated. It happens (the 2 times when I was blowing) when I am on grass going through around a foot of snow, possibly both times after one of my auger shear pins had gone, once going up a hill. In all cases, I do not contact the grass with the auger, although I am close enough that occasionally the grass will show in a tread impression. 

*PS -* I've ordered more pins, I am ordering skid plates, and I was going into this thread to stop people posting. I learned - I am NOT going to be EVIL and use bolts. Then I found your two posts, and the issue of why the drive "wheel" would have problems remains unknown, so here I go extending this thread.


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## wow08816

Using harden bolts in place of shear pins isn't EVIL... it's stupid. Shear pins break to prevent further damage to blower. Using harden bolts defeats this purpose.

Skid shoes are great! But I have cheap concrete and the metal shoes were eroding my walkways.

I swapped out my skid shoes for scooter wheels (they come in all sizes) on my Ariens ST1332DLE blower to make it easier for wife to maneuver unit in garage and to reduce stress on my sidewalks (builder used cheap grade concrete). Another advantage of a wheel is that they last longer. The wheels in the pictures below are over 13 years old. 

My wheel and bearing size varied based on brand of blower. 
- 13HP Ariens required a 85mm wheel with a 9x22x7mm bearing
- 9.5HP Craftsman required a 70mm wheel with a 8x22x7 bearing
- 6.5HP Husqvarna required a 80mm wheel with a 8x22x7 bearing


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## 524SWE

Another person who should be letting his dealer do his maintenance instead of surfing the internet for answers to questions that shouldn't be asked!


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## hobkirk

524SWE said:


> Another person who should be letting his dealer do his maintenance instead of surfing the internet for answers to questions that shouldn't be asked!


And screw you! If you read the thread, you saw I probably found the answer. And my Honda dealer did NOT suggest that solution 

So YOU take your machine to YOUR dealer.


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## 524SWE

hobkirk said:


> and screw you! If you read the thread, you saw i probably found the answer. And my honda dealer did not suggest that solution
> 
> so you take your machine to your dealer.


lol!


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## FearlessFront

hobkirk said:


> I ask my question with trepidation. I ran my own VW/Audi/Porsche repair shop for 15 years, although I was never a mechanic. I.e., I appreciate good engineering.
> 
> In 10-15 hours of operation, 90% clearing driveways and walkways, I have had to replace a lot of shear pins:
> 
> *Maybe 12-16 shear pins on the auger*s (only 2 of which were caused by objects I could discover)
> None on the two collar assemblies that the auger shear pins bolt into.
> *2 on the left drive wheel*
> *1 on the impeller *(subject of another post) - and I used the special and unique Honda bolt
> None of the front of the impeller shaft (at the auger end)
> 
> Why?
> 
> My local dealer says Honda shear pins do seem to need to be replaced more often than other brands, although he's primarily Honda.
> *Is there something wrong with my workmanship or my machine?* The "collar" on my R (?) is slightly loose - it does not lock rigidly to the shaft, there is some play. But I think I break shear pins on the R and L about equally. Whenever I go into the bucket, I verify that the nuts on all the pins are tight.
> *Any suggestions on where to buy them and save a little money?*
> 
> Solution?
> 
> Use 8.8 grade bolts? Or stainless (I've never checked their specs.)
> Just keep buying more?
> 
> Thanks


If you use hardened bolts you'll end up doing permanent damage to the machine like bending the auger/impeller, busting gears and bearings. Maybe you can try the slotted shear pins instead of the shear bolts but don't used hardened bolts it will destroy your machines bucket. :hellno:


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## jrom

hobkirk said:


> *...the hole in the tractor wheel is elongated...*


*

Can you take a photo of that? ...and post it?

It is possible that there's slop or play happening, causing the drive shaft to engage the wheel with too much torque which may break the pin.

I agree with Marlow and dhazelton, it's not a shear bolt. Honda calls shear pins "shear bolts" and the part number you posted is a pin held in place with a cotter pin. I think if there's enough torque, you can snap that pin pretty fast.*


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