Snowblower: Vibrates Excessively

The auger bearings in your snow blower hold the horizontal shaft that extends out of the gearbox. This is what the augers are attached to. Bearings hold the auger shaft firmly in place, allowing them to rotate with ease. If these bearings seize or become worn, it will be difficult for the engine to turn the augers, which can cause the snow blower to vibrate excessively. The rear auger shaft that drives the auger also has a bearing that can cause the same problem. To access the bearings, the gearbox and augers must be removed from their housing. These bearings should spin freely with little to no resistance. If one or more of these bearings do not spin freely, they will need to be replaced. Remove the belt cover and belt from the auger drive pulley. You can do this by simply rolling the belt off. Release the tension on the drive wheel pulley belt, and slide the belt off. Remove the bolts, fastening down the front roller bracket, and set the bracket aside. Take the auger drive spring off the idler pulley bracket. Remove the bolts that attach the auger housing to the snow blower, separate the two halves, and rest the back part on the handles. The impeller should be secured – you can use a piece of wood to do this – to prevent movement as you loosen the bolts that hold the auger drive pulley in place. Make sure you also remove the washer with the pulley and the hub. Remove the bolts holding the gear box onto the support bracket. Remove the bolts that secure the bearing holders on the auger shaft. You can now carefully slide the pull the auger assembly out of the unit. To replace the rear auger house bearing, remove the locking nuts on the bearing retainer, then remove the retainer, and pull off the old bearing. Install the new auger housing bearing into the snow blower, reinstall the retainer, and the locking nuts. Remove the bearing holder and bearings on the ends of the shaft. Install new bearings. Put the auger assembly back into the auger housing, aligning the rear shaft with the rear bearing. Reinstall the bolts, and the bearing holders. Reinstall the pulley hub and the drive pulley. Make sure you tighten down the bolt with the washer, and secure the impeller with a piece of wood while you tighten down the bolt. Reattach the two halves of your snow blower back together, and fasten the bolts. Reconnect the auger drive cable spring to the idler pulley bracket. Reattach the front roller bracket to the frame. Now you can feed the belts back onto the engine drive pulleys, reapplying the tension on the drive wheel belt, and rolling the auger belt back over the drive pulley. To finish the repair, you need to reinstall the belt cover.

The auger belt transmits power from the snow blower engine to the auger. If the belt is thinning out, it may jump and shake all over the pulleys, which will cause excessive vibration. This repair will vary depending on your exact model, but the process should be similar to what we outline here. Remove the belt cover, and roll the auger belt off the front engine pulley. Tilt your snow blower forward, resting it on the auger housing, allowing you to gain access to the transmission. Remove the plate covering the transmission. Loosen and remove the screw that holds the belt onto the auger pulley. Disengage the auger spring from the brake bracket on the frame. Hold down the drive lever with a clamp, which will make it easier to remove the old auger belt. Inspect the auger belt at this time for thinner sections, cracks, damage, or any stretching. This will help you determine the area along the belt that is causing the problem. If needed, install a new augur belt around the auger pulley and housing. Reinstall the screw to hold the belt on the pulley. Reconnect the auger spring to the brake bracket. Put the transmission cover back into place, and tip the snow blower into an upright position. Roll the auger belt over the pulley and under the belt tensioner. This will allow the tensioner to keep pressure on the belt. Finally, you need to reinstall the belt cover.

Bushings are located inside shaft holes on the blade assembly. They form a tight grip between the blade and the drive shaft. They prevent vibration and slippage during operation. Over time, bushings will more than likely wear down and start to come loose. If your bushings have some play in them and are left long enough that this becomes excessive, it could cause severe vibrations. Shake the blades back and forth to check for play, and if you notice any play, change these bushings. To start this repair, remove the belt cover and roll the auger belt off the drive pulley. You should then release the tension on the drive wheel belt, and remove the belt from the pulley. Remove the bolts that secure the front roller bracket, and then remove the bracket. Disengage the auger drive spring from the idler pulley bracket. Remove the bolts securing the auger housing to the snow blower. This will let you separate the two halves, making this repair much easier. You safely can rest the back part on the handles while you are working on the front half of the machine. Secure the impeller with a piece of wood – this stops the impeller from moving as you loosen the bolts on the auger drive pulley. Remove the washer and pulley with the hub. Remove the bolts that secure the bearing holders on the auger shaft. Carefully slide the auger assembly out of the auger housing. Remove the bearing holders with the bearings, washers, and spacers. Pull the shear pins out, so you can slide the auger blade off and remove the bushings. Once you have taken the old bushings off the auger blade, you can install new bushings. Slide the blade back onto the auger shaft and insert the shear pins. Then reinstall spacers, washers, and bearings with the bearing holders. Put the impeller back onto the rear gear box shaft, and reinsert the auger assembly into the housing. Make sure you align the rear gear box shaft into the rear bearing. Reinstall the bearing holders. Reinstall the pulley hub, the drive pulley, the washer, and the bolt. Secure the impeller with a piece of wood to prevent movement as you tighten the bolts. Reattach the two halves of the snow blower, and tighten the bolts to ensure the connection is secure. Hook the auger drive cable spring to the idler pulley bracket. Reattach the front roller bracket to the frame, and feed the belts back onto the engine drive pulley, and underneath the belt tensioner. Reapply the tension on the drive wheel belt, then reinstall the belt cover. Remember to grease any grease fittings before using.

Check that the engine mounts are firmly in place, ensure all the connections are secure, and tighten any loose bolts. Loose engine mounts will cause the engine to vibrate while it’s running. While you are checking the engine mount, you should also be on the lookout for any cracks or damage around the engine mounts. If you notice any cracks you may need to weld them, or fabricate a mounting plate big enough to cover the cracks that the engine can bolt into.