I have an Ariens 926LE snowblower. The blower spins but the auger spins slowly. It barely throws snow. Some times the auger stops spinning. Shear pins are fine.

Hi, The blower spins at full speed? If it does the belt, pulley, and shaft are good. Look at the shaft from the fan to the gear box while it's running and that shaft should be turning at the speed of the fan.
If the blower spins at full speed and the auger doesn't the most likely problem is the worm gear transmission from the blower shaft to the auger shaft.
A good way to visually inspect this is: With the machine turned off and the spark plug wire unhooked go to the front and try to rotate the auger by hand. If the gear box is good you will only be able to move the auger less than an inch. If the box is bad you will be able to move the auger a lot farther. While you are there recheck your shear pins.
You can also remove the blower drive belt and have someone turn the pulley by hand while you watch the auger. Put resistance on the auger with your gloved hand. If the box is good the auger will move smoothly in you hand. If it is bad, it will ****, move roughly, or stop.
While the other person is turning the pulley and you have some resistance on the auger look closely at the shaft running from the gearbox back to the blower. On some models there is a connecting sleeve and the roll pin that connects the sleeve to the shaft and gearbox will break.
If the gearbox is bad, it will have to be replaced as a complete unit.
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