Jeep Cherokee Forum - How to remove a broken bolt

How to remove a broken bolt

Tools needed;

1.Heat gun/soldering gun (heats at least to 900°F, especially useful if the bolts are seized or glued in with RTV silicone like mine were in my differential),
2. Drill,
3. Metal File,
4. Set of extractor drill bits (common name Easyout),
5. Drill bits made of cobalt (not the brand) works great for drilling small diameter holes in the bolt,
6. Carbide tipped drill bits (works well for drilling large diameter holes in the bolt),
7. Hammer,
8. Tap handle,
9. Pliers and/or Channel locks,
10. Center punch
12. WD-40 or liquid wrench may also be useful.
13. Might need Jack and jack stands possibly cinder blocks and tire iron.

DIRECTIONS

If you are dealing with a bolt in the top half of the differential remove the wheels, jack the jeep up, use jack stands to support the vehicle on its frame as close to the axle as is safe. If your jack stands arent tall enough place them on cinder blocks. This will allow the axle to hang bringing the differential below the gas tank.

If the bolt is glued in with RTV silicone use the heat gun/soldering gun to soften the silicone by placing the tip on the top of the bolt for at least 1 minute (follow directions that came with heat gun/soldering gun). Heating between steps may be beneficial.

If the surface you are drilling into is not flat use a file if possible to file down the surface so it is flat (it is nearly impossible to center the drill bit on an uneven surface). If you cannot use the file to even out the surface use the cobalt drill bit to start a hole as close to center as possible.

Once the hole is about 2mm deep use a carbide tipped drill bit (the same size as the bolt) to flatten out the surface . This may require gently moving the drill bit in all directions to create a flat surface to center the bit on.

Once the surface of the bolt is flat or drilled down, use the correct size cobalt bit to drill a hole into the broken bolt at least 1/3 of the way through (be careful not to bend the drill bit or break it off inside the bolt (see directions below if it breaks off inside the bolt).

Tap the appropriate sized bolt extractor into the hole in the broken bolt using a hammer.

Use the pliers, channel locks or tap handle to turn the extractor counter clockwise. The bolt should start coming out.

If the bolt cannot be turned by hand: spray it with some WD-40 or liquid wrench. Let it sit for a little while then try again(if possible hit the top of the bolt with a hammer after letting it sit might help loosen it up)

If it still wont budge use the drill. First, hammer the extractor bit into the hole then put the drill on it. With the drill in the reverse position apply a small amount of power (go slow) or the extractor bit will not be able to catch on the inside of the bolt.

If the bolt cannot be removed because it is stuck or one of the bits breaks off inside of the bolt you will need to use a carbide or cobalt drill bit to completely drill out the bolt. This will completely destroy the bolt by reducing it to shavings. If this is done the hole that the bolt was in will probably need to be re-threaded.