Need to replace a ground strap that's attached on both ends with small M6 bolts going into aluminum. They feel tight so I don't want to twist too much and break the heads off. Yes I soaked them but that won't get under the head to the threads. Would lightly air hammering with a pointy end on the center of the head while turn the bolt with a box end wrench help?
Removing seized bolts with the aid of an air hammer.
- Thread starter atikovi
- Start date
Heat.
1) Heat will just expand the bolt and make it tighter in the hole.
2) Heat will soften the bolt and the head will snap off easier.
What you are trying to do is break the corrosive bond between the two dissimilar metals. Whacking it with an air hammer might break the bond. But applying heat and then quenching the bolt to rapidly cool it will also break the bond
Heat it, whack the head with a punch, then put a box end wrench on it and give it taps with a small ball peen hammer in both directions. Once the head is free, work it back and forth slowly as you back it out.
Quenching the bolt is a good idea.
IS the bolt steel, stainless or is is aluminum in aluminum? Blind hole ( like an head or block?)or is it thin aluminum?
Quenching the bolt is a good idea.
IS the bolt steel, stainless or is is aluminum in aluminum? Blind hole ( like an head or block?)or is it thin aluminum?
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Steel bolts into blind aluminum.
Steel should not be that dissimilar, stainless in aluminum would be a pain as its dissimilar and soft. Heating it, whacking it and the box end wrench tapping method should work.
It it does break off, mig weld a nut to the bolt, the heat from that usually breaks it free.
Worked great. Loosened the bolt in seconds. Now the other end isn't so accessible but we'll see.
This for the win. I have successfully removed many many broken LSx exhaust manifold bolts and a lot of them are below the surface. I hit the end of the bolt with a die grinder to get a little spot clean then weld a little spot on the end of the bolt. I then set a 3/8 nut over it and plug weld through. Then I let the heat soak for about a 20 count and hit it with a 3/8 impact. The first bump usually breaks the weld off at the bolt. At that point you have a nice clean bolt to weld to. My experience is that if it doesn’t come the first try it will on the second go. Keep in mind that aluminum has a thermal expansion rate that is way more than steel so when your weld heat wicks in the bolt is no longer bound. IMHOGiven THAT location I wouldn't be afraid as drilling and tapping a second location would be a breeze if necessary. NOW, it sounds like the OTHER end may be a very different story.
Part 2 a success also. Had to move the fuse box aside to get a straight shot and get creative with the tools, but got it done. Should I use anti-seize on the bolts going back in or is that an insulator and would mess up the ground?
Nice! I think antiseize would be fine, permatex al would work. I would probably not lt use an antiseize with nickel in lt.
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heat around the bolt to expand the surrounding metal, not on the bolt. Common AZ is metallic particles in an oil carrier. It conducts because it's basically metal after the oil evaporates/disappears.
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