Manual Matters

Home › Snow Blowers

Snow Blower Shear Pin Replacement: Signs a Pin Broke and How to Replace It

Updated 2026-10-29 · Written and checked by the Manual Matters team against the manufacturer documents listed under Sources.

Short answer: a shear pin is a deliberately weak bolt that connects the auger to its drive shaft on a two-stage snow blower. When the auger hits something solid, the pin breaks so the gearbox does not. If your machine starts pushing snow instead of throwing it, or one side of the auger spins freely on the shaft, a pin has sheared. Replace it with the exact OEM pin listed in your manual, never with an ordinary hardware-store bolt.

Sketch of a two-stage snow blower auger showing a shear pin through the auger tube and shaft on each side
Sketch of a two-stage snow blower auger showing a shear pin through the auger tube and shaft on each side

Signs of a broken shear pin

According to Ariens:

Two-stage machines have at least one shear pin on each side of the auger, so check both.

What you need

Step by step

  1. Make it safe. Stop the engine, remove the key, and disconnect the spark plug wire. Never reach into the auger housing with the engine running.
  2. Find the broken pin. Rotate the auger by hand to locate the pin holes on each side.
  3. Line up the holes. Turn the auger until the holes in the auger tube and the shaft align.
  4. Remove the old pieces. Tap out the broken halves with a screwdriver or punch.
  5. Insert the new OEM pin through the aligned holes.
  6. Fit and tighten the nut. Torque to the value in your manual. If no spec is available, Ariens advises tightening until the nut no longer spins freely, without overtightening.
  7. Reconnect the plug wire and test in light snow.

Why the OEM pin matters

A shear pin is engineered to fail at a specific load. Ariens stresses using the correct pin from your manual. A stronger bolt will not shear, which can pass the shock into the gearbox instead.

Keep spares on the machine

Many owners tape spare pins to the handle or keep them in a bag with the machine. For end-of-season care, see snow blower off-season storage. For fuel questions, see Run it dry or stabilize it?, and for engine oil choices in cold weather, the Briggs oil type guide explains why SAE 30 is a poor cold-start choice.

Seven steps to replace a snow blower shear pin, from making it safe to testing in light snow
Seven steps to replace a snow blower shear pin, from making it safe to testing in light snow

FAQ

Can I use a regular bolt instead of a shear pin?

Ariens says to use the correct OEM shear pin. A regular bolt may not break when it should, which defeats the purpose of the pin.

Do single-stage snow blowers have shear pins?

Ariens's guidance is written for two-stage machines, which have at least one pin per side. Check your manual for your model.

How tight should a shear pin nut be?

Use the torque in your owner's manual. If it is not available, Ariens says to tighten until the nut no longer spins freely, and not to overtighten.

Why do shear pins keep breaking?

Repeated breaks usually mean the auger is hitting hard objects, ice chunks or a jam. If pins break with no obvious cause, have a dealer inspect the auger and gearbox.

Sources