How to Break a Bolt Loose

We have all seen or experienced it: That stuck bolt that refuses to move when we apply normal or excessive pressure on it with a wrench. Bolts freeze up and jam for various reasons. Corrosion and rust causes the bolts to freeze in the thread grooves. Bolts can stretch beyond their limit length, causing a thread lengthening. Bolts deform when subjected to constant high and low temperatures. There are a number of techniques you can use if your are facing a bolt that refuses to move.

Instructions

1

Scrub the edge of the bolt surface with a wire brush. Remove the grime near the bottom of the bolt where it seats to the metal surface to create an unobstructed path for the penetrating oil. Spray the bolt with liberal amounts of penetrating oil. Wait for at least several minutes for the penetrating oil to seep into the bolt seam. Place a six-point socket or six-point end wrench over the bolt head and twist counterclockwise. Be sure you do not have reverse threads.

2

Rock the wrench back and forth from clockwise to counterclockwise. An end wrench works best for this. Increase the pressure as you move it back and forth. Use a hammer to tap the wrench on both sides, but do so gently at first. If it breaks free, move the wrench counterclockwise a few more turns, then spray more penetrating oil into the base of the bolt. To protect the bolt from stretch and damage, rock it gradually all the way out.

3

Spray penetrating oil at the base of the bolt and let it soak for at least several minutes. Use a hammer to strike the top of the bolt head a few times. Use firm, but not excessive blows. This will shock and loosen corrosion in the threads. Remove the bolt with an end wrench and extra penetrating oil. Rock it out, if you wish.

4

Spray penetrating oil on the bolt and let it soak. Connect a six-point socket to an air impact gun. Set the pressure dial on the air impact gun for "low" pressure. Attach the gun and socket to the bolt head and pull the trigger. Reverse the gun to the extraction setting and pull the trigger. Use this rotation back and forth while you dial up the pressure setting on the gun to increase the torque. The hammering blows of the air ratchet gun should free up the bolt.

5

Turn on a propane torch to high heat. Make sure you have nothing flammable in the area of the bolt, including wires or rubber seals. Direct the flame near the edge of the bolt head. Do not heat the bolt head but heat the metal surface area around it. This will expand the bolt hole threads outward, allowing the bolt threads to remain contracted. Immediately apply a wrench to the bolt and twist it counterclockwise.

6

Examine the bolt head for damage. If the head appears broken or stripped, use a hammer and center punch to mark its center. Use a power drill and appropriate size bit to drill about one inch into the top of the bolt head. Place an end wrench on a bolt extractor bit, then shove the bit into the drill hole. Twist the bolt out counterclockwise. The reverse cutting tips on the bolt extractor will grab the inside surface of the bolt, forcing it to turn.