another brake problem
Thread Starter
Racer
Joined: Sep 2003
Posts: 353
Likes: 1
From: Long Island, New York
another brake problem
Passanger side had no problem - drivers side I can't get the hex bolts out 
I actually drilled out the top one but on the bottom bolt as I was using the extractor it sheared off inside the shank. This same bolt actually sheared off the 10mm hex head of my ratchet as I tried to loosen it up. I tried to drill through the sheared extractor piece but its way harder than the bolt - any suggestions?
I actually drilled out the top one but on the bottom bolt as I was using the extractor it sheared off inside the shank. This same bolt actually sheared off the 10mm hex head of my ratchet as I tried to loosen it up. I tried to drill through the sheared extractor piece but its way harder than the bolt - any suggestions?
Rennlist Member
Joined: Nov 2004
Posts: 5,241
Likes: 1,043
From: DFW Texas
Sorry for the length, but this covers just about every situation with a broken bolt.
Jim Mayzurk
93 GTS 5-spd
Broken Bolt removal: Once the bolt breaks, often the tension is off and it spins out, cleaning and Liquid Wrench helps. If some of the bolt is sticking out, use a screwdriver or pick to turn the bolt. Work the pick around the edge of the bolt to find a lip where it broke. If the threads have stretched or the bolt is bottomed out then the bolt locks in the threads. Try a big pair of vice grips or needle nose vice grips. If enough of the bolt is sticking out, make two flat spots with a Dremel to get a better grip or a screwdriver slot. Tap the end of the screwdriver to seat it and release the threads. Or try a cold chisel to work around the edges, be careful not to hit the block. Or drill; use a small grinder or a Dremel to grind a flat spot on the bolt to allow for an accurate center punch. Drill a small pilot hole in the center, don’t break the bit in the bolt and create a bigger problem. Once you have the pilot hole use an Easy Out. If that fails, re-drill the bolt, with the correct drill for a tap or just smaller. This leaves the threads of the bolt in the hole but with no strength to hold them together. With a pick or small cold chisel and a pair of needle nose pliers, work the threads out. If this works it’s a good idea to clean the threads with a bottom tap before replacing the bolt. Finally if all else fails use a larger bit to drill out the rest of the threads and install a Time Cert. Use Red Loctite on the Time Cert, not on the threads of the bolt, so it won’t turn next time you remove it. When drilling be careful not to go to deep. Measure the depth of the other holes and use a piece of tape on the drill to mark the depth. If all else fails use an epoxy to fill the hole completely, then re-drill and tap in a new thread, this is the worst solution. Be sure to get epoxy that can take the recommended torque. Clean the surface real good before using the epoxy. If you break a tap in the hole, you may be surprised at what the Dremel tool can accomplish using a diamond bit. If the diamond bit is small enough, you may be able to cut away the web (center section or body of the tap) without getting too close to the existing thread in the hole. A diamond cutting tool will be harder than the tap material. There are also tap extractors for removing broken taps, that have fingers that slide down the flutes of the tap coupled to a square drive on the top of the tool. They will sometimes work, but usually in cases where you can already partially turn the broken tap. Or build a small 3-pin wrench with a piece of steel 1/4" thick, preferably 3/8". It can be any size as long as you have an open-end or adjustable wrench that can span two sides, or ideally your piece of 1/4" or 3/8" steel is long enough to be used as a handle. You’ll need a drill press to be able to do a decent job. You need 3 (or number of tap flutes) steel roll pins that can fit into the flutes of the broken tap and clear the internal diameter of the tapped hole in your block. You’ll have to drill the piece of steel in a small, tight pattern that mimics the flute spacing of the tap. The roll pins have to be driven into the holes you drill in the steel piece. If you use 1/4" plate, the pins should not be longer than 5/8". If you use 3/8" plate they could be 3/4" long. Hold each pin with needle nose pliers as you hammer it into the drilled holes. If the tap broke when bottomed out, this tool seldom works. The tap is made from high carbon steel so you can soften it by a reverse heat-treatment process called "normalizing". Use non-flammable, no-residue cleaning agent on the broken tap/hole area and remove any traces of oil or cutting fluids. Be thorough, so you don't start a fire! Adjust a propane torch flame to a very small, concentrated cone, about 1/2" long. Carefully heat the exposed end of the tap to make it glow cherry red, and keep it at this temperature/color for 3 or 4 minutes. Don’t let the flame wander to the aluminum block. More time won't hurt, but less will not allow the metallurgical reaction to take place. You must get the entire broken tap glowing. Remove the heat, and allow to slow cool in the air. This won’t hurt the aluminum block! It will soften the tap so a drill bit will cut it. Also, because of the different expansion rates between aluminum and steel, the act of warming the faster-expanding aluminum can often release a stuck steel part. In this case, you heat the surrounding aluminum alloy and avoid the steel part as much as possible. In the event that something may catch on fire, keep something nearby to smother NOT douse the flames. Another alternative if enough of the broken tap or fastener remains outside the hole, you can weld a nut on the broken piece. Center the nut over the broken stub and weld into the hole in the nut, filling it up. Allow to slowly cool in air. Use a wrench to turn the nut and remove the broken piece. If you can soften the tap by the method above, you may be able to make due with cobalt or titanium-coated drill bit (gold color). Left-handed drill bits are better in these situations as they rotate counter-clockwise. Use a left hand drill bit with a hand feed only, not power feed! Use a very slow spindle speed, about 20-50 rpm. Because you’ve pre-drilled the small diameter hole in the center of the broken bolt, the drill point doesn’t apply any downward force on the broken bolt (the drill point contacts air, not metal!). The two cutting lips on the end of the drill bit bite into the broken bolt material and apply sufficient torque that the left hand drill bit will often cause the broken bolt to un-screw itself right out of the hole. This is why hand feed and low spindle speed are essential. You’ll have to allow for the rapid upward movement of the broken bolt as it comes out of the hole! If you don't, you will break the drill bit, or worse, damage the female threads in the soft aluminum block. This is the best method to remove a broken fastener, and usually this method will remove the broken fastener without damaging the surrounding threads. After you remove the broken bolt, be sure to use the proper size tap to chase the internal threads so they’re clean for reassembly. This is a good practice to use on all drilled and tapped holes anyway during any kind of a rebuild. When faced with a stuck bolt that doesn't give easily when you attempt to remove it, before you break it give the bolt a hard hit in the middle with a center punch. This will often break the threads free. Also, use soft Sears taps rather than hard tungsten carbide taps. Considering the block is aluminum, and if it breaks, removal isn't such a bear.
Jim Mayzurk
93 GTS 5-spd
Broken Bolt removal: Once the bolt breaks, often the tension is off and it spins out, cleaning and Liquid Wrench helps. If some of the bolt is sticking out, use a screwdriver or pick to turn the bolt. Work the pick around the edge of the bolt to find a lip where it broke. If the threads have stretched or the bolt is bottomed out then the bolt locks in the threads. Try a big pair of vice grips or needle nose vice grips. If enough of the bolt is sticking out, make two flat spots with a Dremel to get a better grip or a screwdriver slot. Tap the end of the screwdriver to seat it and release the threads. Or try a cold chisel to work around the edges, be careful not to hit the block. Or drill; use a small grinder or a Dremel to grind a flat spot on the bolt to allow for an accurate center punch. Drill a small pilot hole in the center, don’t break the bit in the bolt and create a bigger problem. Once you have the pilot hole use an Easy Out. If that fails, re-drill the bolt, with the correct drill for a tap or just smaller. This leaves the threads of the bolt in the hole but with no strength to hold them together. With a pick or small cold chisel and a pair of needle nose pliers, work the threads out. If this works it’s a good idea to clean the threads with a bottom tap before replacing the bolt. Finally if all else fails use a larger bit to drill out the rest of the threads and install a Time Cert. Use Red Loctite on the Time Cert, not on the threads of the bolt, so it won’t turn next time you remove it. When drilling be careful not to go to deep. Measure the depth of the other holes and use a piece of tape on the drill to mark the depth. If all else fails use an epoxy to fill the hole completely, then re-drill and tap in a new thread, this is the worst solution. Be sure to get epoxy that can take the recommended torque. Clean the surface real good before using the epoxy. If you break a tap in the hole, you may be surprised at what the Dremel tool can accomplish using a diamond bit. If the diamond bit is small enough, you may be able to cut away the web (center section or body of the tap) without getting too close to the existing thread in the hole. A diamond cutting tool will be harder than the tap material. There are also tap extractors for removing broken taps, that have fingers that slide down the flutes of the tap coupled to a square drive on the top of the tool. They will sometimes work, but usually in cases where you can already partially turn the broken tap. Or build a small 3-pin wrench with a piece of steel 1/4" thick, preferably 3/8". It can be any size as long as you have an open-end or adjustable wrench that can span two sides, or ideally your piece of 1/4" or 3/8" steel is long enough to be used as a handle. You’ll need a drill press to be able to do a decent job. You need 3 (or number of tap flutes) steel roll pins that can fit into the flutes of the broken tap and clear the internal diameter of the tapped hole in your block. You’ll have to drill the piece of steel in a small, tight pattern that mimics the flute spacing of the tap. The roll pins have to be driven into the holes you drill in the steel piece. If you use 1/4" plate, the pins should not be longer than 5/8". If you use 3/8" plate they could be 3/4" long. Hold each pin with needle nose pliers as you hammer it into the drilled holes. If the tap broke when bottomed out, this tool seldom works. The tap is made from high carbon steel so you can soften it by a reverse heat-treatment process called "normalizing". Use non-flammable, no-residue cleaning agent on the broken tap/hole area and remove any traces of oil or cutting fluids. Be thorough, so you don't start a fire! Adjust a propane torch flame to a very small, concentrated cone, about 1/2" long. Carefully heat the exposed end of the tap to make it glow cherry red, and keep it at this temperature/color for 3 or 4 minutes. Don’t let the flame wander to the aluminum block. More time won't hurt, but less will not allow the metallurgical reaction to take place. You must get the entire broken tap glowing. Remove the heat, and allow to slow cool in the air. This won’t hurt the aluminum block! It will soften the tap so a drill bit will cut it. Also, because of the different expansion rates between aluminum and steel, the act of warming the faster-expanding aluminum can often release a stuck steel part. In this case, you heat the surrounding aluminum alloy and avoid the steel part as much as possible. In the event that something may catch on fire, keep something nearby to smother NOT douse the flames. Another alternative if enough of the broken tap or fastener remains outside the hole, you can weld a nut on the broken piece. Center the nut over the broken stub and weld into the hole in the nut, filling it up. Allow to slowly cool in air. Use a wrench to turn the nut and remove the broken piece. If you can soften the tap by the method above, you may be able to make due with cobalt or titanium-coated drill bit (gold color). Left-handed drill bits are better in these situations as they rotate counter-clockwise. Use a left hand drill bit with a hand feed only, not power feed! Use a very slow spindle speed, about 20-50 rpm. Because you’ve pre-drilled the small diameter hole in the center of the broken bolt, the drill point doesn’t apply any downward force on the broken bolt (the drill point contacts air, not metal!). The two cutting lips on the end of the drill bit bite into the broken bolt material and apply sufficient torque that the left hand drill bit will often cause the broken bolt to un-screw itself right out of the hole. This is why hand feed and low spindle speed are essential. You’ll have to allow for the rapid upward movement of the broken bolt as it comes out of the hole! If you don't, you will break the drill bit, or worse, damage the female threads in the soft aluminum block. This is the best method to remove a broken fastener, and usually this method will remove the broken fastener without damaging the surrounding threads. After you remove the broken bolt, be sure to use the proper size tap to chase the internal threads so they’re clean for reassembly. This is a good practice to use on all drilled and tapped holes anyway during any kind of a rebuild. When faced with a stuck bolt that doesn't give easily when you attempt to remove it, before you break it give the bolt a hard hit in the middle with a center punch. This will often break the threads free. Also, use soft Sears taps rather than hard tungsten carbide taps. Considering the block is aluminum, and if it breaks, removal isn't such a bear.
Rennlist Member
Joined: Dec 2002
Posts: 5,283
Likes: 52
From: Australia
If access is enough, try cutting through the extractor fragment with a dremel grinding disc, or a carbide bit which is very hard. The discs can also be used to split the bolt head(cut down to the bottom of the head, cold chisel into the cut), but if the caliperneeds to lift off at right angles to the bolt, this wont help you much.
jp 83 Euro S at 49k
jp 83 Euro S at 49k