You know when you are really tired of working a car and it seems like it's been nothing but stupid little things that keep occuring to make the work never end, and when you are right at the end you break the head off a bolt, once again adding another few hours when you thought you were about 5 min away from hitting the shower and getting a nice BJ?

Plus you don't have any easy outs, but that doesn't matter because you wouldn't be able to reach it with a drill anyway, and it's not even your car?

I broke the head off a seemingly fine bolt on Ed/saintfoo's car. I decide to fit his huge Hella horns back in after installing the 18x12x3 core intercooler. This required temporarily removing the hood latch to slide the one horn in, no biggie right. I was about 1/8 turn from being finished with this car...then the wrench gets mushy...

TIG to the rescue!







still no bj though

 

That's a shame. You want me to talk to your BF?

 

How was it stuck enough to break the head off, but still loose enough to come out with needle nose and coat hanger wire? Bolts like that always confuse me, I still can't get my brain on the concept.

We have some posters on here that are fond of giving BJ's.

 

ABSURDhorn

 

I kind of thought that too.

 

Heat from the weld is the key. As it heats up the bolt expands, not having much mass it starts to cool quickly. This rapid expansion and contraction is the main factor in the bolt extraction.

 

Also unless you're bottoming out a bolt, when you torque it, you're using the elastic properties of the bolt to keep it tight, much like a split lock washer works as a spring. When the head twists off from too much torque, it compresses back to it's original size and becomes loose. It just doesn't have anything for you to twist it out with.

 

I always kinda thought that when a head twists off a bolt like that its cause it seized in there. One of the bolts that [used] to hold the starter motor on our integra is backed out half way because it seized. Cant turn it out anymore. Just stopped. Then I stripped it. Oh well.

 

surprised you got it out with just some wire and vice grips! Speaking of bolt expansion and what not, while putting a rusty nut onto rusty threads for the exhaust today, the ratchet heated up to where I could barely hold it. Never new such forces were going on.

 

To give you a good relationship between force and heat, take a nail and lay it on the ground. Whack it with a big hammer a few times real hard to flatten it out, then pick it up. Post the results.