Removing stuck fasteners

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Most stuck fasteners are stuck because of corrosion -- usually [[rust]]. There are two effective means to break the friction that corrosion has caused.  One is through mechanical movement -- often simply a whack with a hammer. The other is through differential heating -- making one part expand more than the other.
 
Most stuck fasteners are stuck because of corrosion -- usually [[rust]]. There are two effective means to break the friction that corrosion has caused.  One is through mechanical movement -- often simply a whack with a hammer. The other is through differential heating -- making one part expand more than the other.
  
*With heating, bear in mind axles and other important structures may lose their strength if they are heated much above 300 degrees. If you have the oil and grease starting to smoke, then you are in the 300-degree range.
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===Tighten, then loosen===
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In some cases, simply tightening the fastener and then loosening it will do the trick. In some cases, wiggling the fastener back and forth may be helpful.
  
*When taking off cylinder head studs, look at the base. If you see erosion into the stud at the block surface, odds are pretty good you will break the stud.
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===Smack it with a hammer===
 
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Though this may not be practical for all situations, a stuck bolt can often be broken loose simply by hitting it on the head with a hammer. In such a case, a brass drift may be helpful. Drifts of varying lengths can be made from brass bar, and used to access hidden bolts. Brass is used because it's softer, and thus less likely to damage the head of a fastener. Brass hammers are also available and one about 3 or 4 lbs. in weight is good for this.
*Whatever system you use, once you have a hold of the bolt, stud, or whatever, try rocking it forward and reverse a little at a time. If you can get it to move, it is more likely to come out. An older mechanic said always try to tighten a little before you loosen. Remember, if it moves, you are half way home. Also, brake fluid works great as a penetration oil.
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==Tighten, then loosen==
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Another option is to get a wrench or ratchet onto the stuck fastener, and then hit the wrench or ratchet with a hammer.
In some cases, simply tightening the fastener and then loosening it will do the trick.
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==Smack it with a hammer==
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If you can access the nut, try hitting each flat of the nut with a drift punch and ball peen hammer.
Though this may not be practical for all situations, a stuck bolt can often be broken loose simply by hitting it on the head with a hammer. In such a case, a brass drift may be helpful. Drifts of varying lengths can be made from brass bar, and used to access hidden bolts. Brass is used because it's softer, and thus less likely to damage the head of a fastener(However the problem with brass is it will absorb some of the shock of the blow from the hammer, so one may need to use a melt drift for maximum shock to the bolt).  Brass hammers are also available and one about 3 or 4 lbs. in weight is good for this.
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If I could have only one chemical tool, it would be "Liquid Wrench".  Note that when trying to loosen rusty parts, it's important to first remove as much of the rust as possible with a wire brush.  Once it's as clean as a wire brush will get it, apply Liquid Wrench, then give the piece repeated light taps with a hammer for ten or fifteen seconds; this helps work the Liquid Wrench into the crevices.  Wait two minutes, then repeat the Liquid Wrench/tapping procedure.  After repeating the procedure 3 or 4 times, THEN try to loosen it with one swift blow.  Sometimes it won't work, but the majority of the time, your patience will allow you to not only remove the rusted nuts and bolts, but to possibly even reuse them.
 
If I could have only one chemical tool, it would be "Liquid Wrench".  Note that when trying to loosen rusty parts, it's important to first remove as much of the rust as possible with a wire brush.  Once it's as clean as a wire brush will get it, apply Liquid Wrench, then give the piece repeated light taps with a hammer for ten or fifteen seconds; this helps work the Liquid Wrench into the crevices.  Wait two minutes, then repeat the Liquid Wrench/tapping procedure.  After repeating the procedure 3 or 4 times, THEN try to loosen it with one swift blow.  Sometimes it won't work, but the majority of the time, your patience will allow you to not only remove the rusted nuts and bolts, but to possibly even reuse them.
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The best thing to do is to get a wrench or ratchet on it, and either hit it with your hand or a hammer several times.  The sudden force will break the bolt loose with less of a chance of twisting off the head.
 
The best thing to do is to get a wrench or ratchet on it, and either hit it with your hand or a hammer several times.  The sudden force will break the bolt loose with less of a chance of twisting off the head.
 
If you can get to the nut, try hitting each flat of the nut with a drift punch and ball pein hammer.
 
  
 
Some times a home made impact wrench will work, get a cheap wrench that fits tight and hit it with a hammer watching carefully that it isn't coming off the fastener. It's important when loosening this way to use a tight fitting wrench as a loose fitting one will round the bolt head.
 
Some times a home made impact wrench will work, get a cheap wrench that fits tight and hit it with a hammer watching carefully that it isn't coming off the fastener. It's important when loosening this way to use a tight fitting wrench as a loose fitting one will round the bolt head.
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*If you break off the head of the bolt, grind the remainder out with care using a TrueBite carbide bit and a high-speed rotary tool (Dremel MotoTool or some such) - see http://www.truebite.com/remove/ for details and instructions.
 
*If you break off the head of the bolt, grind the remainder out with care using a TrueBite carbide bit and a high-speed rotary tool (Dremel MotoTool or some such) - see http://www.truebite.com/remove/ for details and instructions.
 
*Besides the Comet cleanser tip, another way to give a screwdriver more grip on a screw head is to dip the tip of the screwdriver into a little valve grinding compound, then apply the screwdriver to the screw head. Works well anywhere you need a little more traction to get that stripped screw head out or sometimes can be used on a closed end wrench and slightly rounded off bolt head.
 
*Besides the Comet cleanser tip, another way to give a screwdriver more grip on a screw head is to dip the tip of the screwdriver into a little valve grinding compound, then apply the screwdriver to the screw head. Works well anywhere you need a little more traction to get that stripped screw head out or sometimes can be used on a closed end wrench and slightly rounded off bolt head.
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*With heating, bear in mind axles and other important structures may lose their strength if they are heated much above 300 degrees. If you have the oil and grease starting to smoke, then you are in the 300-degree range.
 +
 +
*When taking off cylinder head studs, look at the base. If you see erosion into the stud at the block surface, odds are pretty good you will break the stud.
 +
 +
*Whatever system you use, once you have a hold of the bolt, stud, or whatever, try rocking it forward and reverse a little at a time. If you can get it to move, it is more likely to come out. An older mechanic said always try to tighten a little before you loosen. Remember, if it moves, you are half way home. Also, brake fluid works great as a penetration oil.
  
 
I've used the largest cobalt drill bit (that almost just covers the top rim of the nut)
 
I've used the largest cobalt drill bit (that almost just covers the top rim of the nut)

Revision as of 21:19, 18 April 2008

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