How do I replace snow blower shear pins?
Stop the engine, remove the key, disconnect the spark plug wire and let everything stop moving. Line up the holes in the auger and the auger shaft, push out the broken half of the pin, fit a new pin of the exact part number in your manual and secure it with its nut, snug but not overtightened. Spin the auger by hand to confirm.
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By Kasra Taheri, Founder, LoclisPublished
Researched and drafted with AI, then checked claim by claim against the sources listed below before it was published. Prices and rules change; the dates beside each source say when it was last checked.
Step by step
Read when to stop and call a pro, further down this page, before you start.
Step 1: Shut the machine down
Stop the engine, remove the key, disconnect the spark plug wire and wait for all moving parts to stop.[1]
Step 2: Confirm the pin is broken
If you do not see the shear pin head or nut and you can spin the auger by hand along the auger shaft, the pin has broken.[1]
Step 3: Clean the shaft
Wipe the auger shaft clean so you can see and reach the pin.[1]
Step 4: Line up the holes
Rotate the auger until the holes in the auger and the auger shaft align.[1]
Step 5: Push out the remains
Push the leftover half of the pin out with a thin screwdriver, or in rare cases tap it out with a flat punch and hammer.[1]
Step 6: Fit the correct new pin
Keep the holes aligned and insert a new shear pin with the part number from the service parts section of your owner's manual.[1]
Step 7: Secure it
Fit the nut and tighten to the torque specification in your operator's manual, without overtightening.[1]
Step 8: Test by hand
Try rotating the auger by hand to confirm the pin is secure before you restart.[1]
The short answer
A broken shear pin is a cheap, intended failure, and replacing it is a quick job once the engine is off and the spark plug wire is disconnected. Line up the holes in the auger and its shaft, push out the broken pin, fit the exact replacement named in your manual and secure it.
What a shear pin is, and why it breaks
A shear pin (also known as a shear bolt) is a weak bolt that connects your auger to the auger shaft.[1] If a large object gets wedged between your augers and the housing, the pins break as designed to protect your auger gearcase from incurring damage.[1] All two-stage snow blowers have at least one shear pin on each side of the auger gear case.[1]
Rocks, large gravel, branches, newspapers, toys and curbs are the usual culprits, so a quick walk over the driveway before the first pass saves a lot of pins.
How to tell it is the pin
If it feels like your snow blower is pushing snow rather than processing it, or if you see snow building up outside either side of your auger housing, you likely broke a shear bolt.[1] The engine still runs and the shaft still turns, but the auger itself does not.
Do the check with the machine off. Ariens says to stop the engine, remove the key, disconnect the spark plug wire from the engine and wait for all moving parts to stop.[1] Then look at the auger. If you do not see the pin head or nut and the auger spins freely along the shaft, the pin has broken.
Replace the pin
Work with the machine off and the wire disconnected, as above, and wipe the auger shaft clean so you can see the holes. Typically, when a shear pin breaks, only half of it will fall out while the other half remains inside the auger shaft hole.[1] Turn the auger by hand until the holes in the auger and the shaft line up, then push the remaining piece out with a thin screwdriver. If it is stuck, a flat punch and a light tap will do it.
Keep the holes aligned, slide the new pin through and fit the nut. Tighten to the torque listed in your operator's manual, and do not overtighten: overtightening could stress the shear pin and result in premature failure.[1] Spin the auger by hand. If it no longer turns freely along the shaft, the pin is secure and you can restart.
Check the pin on the other side while you are there, since the jam may have affected both.
Use the right pin
This is the part people shortcut. Find the part number in the service parts section of your owner's manual, or ask a dealer with your model number. If you use a pin that can handle more torque than your machine, you risk causing extensive damage to your snow blower.[1] The pin should always be the weakest link. Buy a few spares and keep them in the garage, since the next jam usually happens mid-storm.
Clear jams safely
Most snow thrower injuries happen when consumers try to clear snow from the discharge chute or debris from the auger/collectors.[2] CPSC has received reports of injuries with snow throwers, including finger amputations.[2] Its advice is to stop the engine and use a long stick to unclog wet snow and debris from the machine.[2] Never put a hand in the chute, even with the engine idling.
If you move the machine into a garage to do the repair, stop it first: never leave the machine running in an enclosed area.[2]
Stop and call a pro if
- The new pin breaks again right away. Something is still jammed, or the auger or shaft is damaged. Do not swap in a harder bolt.
- The auger will not turn by hand, or the gearcase is noisy, leaking or hot. That points past the pin to the gearcase, which is a shop repair.
- The holes in the auger and shaft are bent or elongated so the pin will not seat.
- You cannot find the correct part number for your model.
- You are not comfortable working next to the auger even with the wire disconnected.
Related help
A shop can also tell you whether the rest of the machine is worth the money: see is it worth repairing an old snow blower and what snow blower repair costs in Virginia. More guides are in small engine repair answers, and you can find local shops under snow blower repair.
If the machine needs more than a pin, post a snow blower repair job and local shops can quote it.
Common questions
- What does a shear pin do?
- It is a weak bolt that connects the auger to the auger shaft. If a large object wedges between the augers and the housing, the pin breaks as designed, which protects the gearcase from damage.[^ariens]
- How do I know a shear pin has broken?
- Ariens says that if the machine feels like it is pushing snow rather than processing it, or snow builds up outside either side of the auger housing, you likely broke a shear bolt. With the engine stopped, you will not see the pin head or nut and the auger spins by hand along the shaft.[^ariens]
- Can I use a stronger bolt from the hardware store?
- No. A pin that can handle more torque than your machine risks extensive damage to the snow blower, because the pin is meant to break first. Use the part number in the service parts section of your owner's manual.[^ariens]
- How many shear pins does my snow blower have?
- Two-stage snow blowers have at least one on each side of the auger gear case.[^ariens] Check the parts diagram for your model, and buy spares, since the next jam is a matter of when.
- Can I clear the jam with my hands before replacing the pin?
- Never. CPSC says most injuries happen when people clear the chute or auger by hand, including finger amputations. Stop the engine and use a long stick.[^cpsc]
Sources
- [1] What are shear pins and why do I need them?, Ariens. Checked October 27, 2026.
- [2] Snow Thrower Safety (Publication 5117), U.S. Consumer Product Safety Commission. Checked October 27, 2026.
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