MTL_4runner
03-28-2007, 07:52 AM
Here's a list of methods complied to help make this process easier.
Loosening Rusted Tight Bolts and Studs
1) Penetrating and Dismantling Oils. Forget about WD-40 and Liquid Wrench (obviously use them as a last resort). The only stuff to buy in the US and Canada is PBBlaster, available at IPD, Walmart and other mass marketers. Kroil is another good brand if you can find it. In the UK, try E.A.C.'s PlusGas Formula A, available from tool and engineers' supply shops.
2) Slight Retightening. Try tightening the offending item, just a little bit, then try loosening it. Since learning that one, it has come in handy mucho times.
3) Bolt Extractor Kit The use of a nut or bolt extractor can dramatically improve your chances of getting off a rusted fastener by giving you a good bite and as you turn it actually works to pull the extractor toward the part. This is far better than a socket when the rust has begun to deform the outside of the nut or bolt head.
http://images.orgill.com/200x200/5652953.jpg
4) Using Heat. Heat the area around the bolt with a propane torch, and touch a candle or beeswax to the threads. The wax will be sucked into the opening around the threads, and the bolt can be removed easily. The heating and candle application may have to be repeated a couple times. This works on the same principle as sweat-soldering copper pipes, and will work where penetrating oil will not. (Always use care when and where you apply heat). In the absence of beeswax, I used Chapstick and it worked as well.
The often a thread-locked part (like a carburetor or throttle body) will risk snapping off a small screw. Usually heat is used to soften up and remove locked fasteners. Then you can use a solvent on the bolt threads to clean the remains. The breakdown temp is usually 400-500 F so try a soldering iron on the screw, or a small pencil torch to direct the heat right where you need it.
5) Using Cold. Gently heat the area around the female side with a heat gun and then spray the male side with a can of electronics freeze (used to locate intermittent breaks on circuit boards). This may shrink the male bolt enough to break the bond and then allow you to first tighten (as above), then loosen. Spray with PBlaster to ensure that it penetrates into the joint.
6) Cutting Off the Offending Nut. When removing rusted or otherwise stuck nuts or bolts, penetrating oil and impact tools can work, but sometimes just make the job more difficult (as when breaking off a fastener below a point where it can easily be accessed). One of the handiest tools is a Dremel type tool (high speed, power rotary tool) . Using the small cut off wheels (approx. 1" in diameter) spinning at high speed (up to 30,000 rpm depending on the tool) these thin, brittle wheels can cut through even the hardest steel. Work from opposite sides of the nut and use a flat screwdriver to pry the halves apart once you have reached sufficient depth. I have also used this method to remove CV axle nuts without damaging the threads. Be aware that a full-face protection shield is recommended and that spectators remove themselves from the area. When these little wheels break they can travel some distance. The wheels are often available in little containers of 25 and although they will break quite often until you get the feel for them they are relatively inexpensive.
Loosening Rusted Tight Bolts and Studs
1) Penetrating and Dismantling Oils. Forget about WD-40 and Liquid Wrench (obviously use them as a last resort). The only stuff to buy in the US and Canada is PBBlaster, available at IPD, Walmart and other mass marketers. Kroil is another good brand if you can find it. In the UK, try E.A.C.'s PlusGas Formula A, available from tool and engineers' supply shops.
2) Slight Retightening. Try tightening the offending item, just a little bit, then try loosening it. Since learning that one, it has come in handy mucho times.
3) Bolt Extractor Kit The use of a nut or bolt extractor can dramatically improve your chances of getting off a rusted fastener by giving you a good bite and as you turn it actually works to pull the extractor toward the part. This is far better than a socket when the rust has begun to deform the outside of the nut or bolt head.
http://images.orgill.com/200x200/5652953.jpg
4) Using Heat. Heat the area around the bolt with a propane torch, and touch a candle or beeswax to the threads. The wax will be sucked into the opening around the threads, and the bolt can be removed easily. The heating and candle application may have to be repeated a couple times. This works on the same principle as sweat-soldering copper pipes, and will work where penetrating oil will not. (Always use care when and where you apply heat). In the absence of beeswax, I used Chapstick and it worked as well.
The often a thread-locked part (like a carburetor or throttle body) will risk snapping off a small screw. Usually heat is used to soften up and remove locked fasteners. Then you can use a solvent on the bolt threads to clean the remains. The breakdown temp is usually 400-500 F so try a soldering iron on the screw, or a small pencil torch to direct the heat right where you need it.
5) Using Cold. Gently heat the area around the female side with a heat gun and then spray the male side with a can of electronics freeze (used to locate intermittent breaks on circuit boards). This may shrink the male bolt enough to break the bond and then allow you to first tighten (as above), then loosen. Spray with PBlaster to ensure that it penetrates into the joint.
6) Cutting Off the Offending Nut. When removing rusted or otherwise stuck nuts or bolts, penetrating oil and impact tools can work, but sometimes just make the job more difficult (as when breaking off a fastener below a point where it can easily be accessed). One of the handiest tools is a Dremel type tool (high speed, power rotary tool) . Using the small cut off wheels (approx. 1" in diameter) spinning at high speed (up to 30,000 rpm depending on the tool) these thin, brittle wheels can cut through even the hardest steel. Work from opposite sides of the nut and use a flat screwdriver to pry the halves apart once you have reached sufficient depth. I have also used this method to remove CV axle nuts without damaging the threads. Be aware that a full-face protection shield is recommended and that spectators remove themselves from the area. When these little wheels break they can travel some distance. The wheels are often available in little containers of 25 and although they will break quite often until you get the feel for them they are relatively inexpensive.