Electric Drill: Chuck Won't Hold Bits

A defective, or worn out, drill chuck, will not be able to hold the tightness on the drill bits and will require replacement. The drill chuck supports the drill bits with jaws that firmly clamp on the bits. Begin by inserting the proper screwdriver into the chuck to remove the screw at the bottom – also known as the chuck screw. Snug the chuck against the screwdriver and loosen by turning clockwise. This screw is reversed thread.

Once you’ve broken the tightness of the screw, loosen the chuck and continue to remove the screw. Insert a big allen key into the chuck and tighten it down. Hit the allen key with a hammer to loosen – this is reversed thread. You may have to hit it a few times for the stubborn ones. When it has loosened, continue to remove it from the spindle. Install the new drill chuck by threading it on the spindle, remembering this is reverse thread. Then, insert the allen key back on the drill chuck and tighten the chuck onto the key. Use the allen key to tighten the drill chuck on the drill, hand tight, then loosen the drill chuck and remove the allen key. Insert the screwdriver inside the drill chuck to tighten the chuck screw, remembering that this screw is reversed thread.

If the chuck screw is not tightened all of the way, it can impact the operation of the clamps. Insert the proper screwdriver into the drill chuck and tighten the screw, remembering that this screw is reversed threaded. Rotate it counter clockwise to tighten. If problems persist, remove the screw and check for stripped threads and replace, if needed.

The key is inserted in the hole, located on the side of the drill chuck, which then locks into a gear. When you turn this key, it will open or close the drill chuck. Ensure you are suing the correct size chuck to lock into the gear, allowing the jaws to open or close.