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X-F250

Broken Bolt Extraction

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G'day guys,

Deankdx suggested I make a thread about how to remove broken bolts, and since I had to do it again today I figured I'd take some photos as I went.

 

Todays patient is my brother's 1990 Telstar.

7ba57aaa59a0f55b1f6aeb36603a5ca6.jpg

He overtightened one of the rocker cover bolts and snapped the head off. Luckily it's a long bolt so there was quite a bit of meat hanging out of the head.

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This is probably the easiest bolt extraction to do since there's plenty of room to get a pair of pliers in.

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Couple of turns and out she comes.

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Next time I'll show how I got the snapped rocker stud in my Falcon out with a Dremel.

 

Sent from my SM-G930F using Tapatalk

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add heat or cold spray causing metal to release..sharp blow with a hammer can have similar effect

 

chisel the edge with either a center punch or chisel

 

drill slightly off center through the broken bolt so it exposes the thread in whatever its stuck in(frees it up) tap undone with punch, screw driver or whatever is handy.
 

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Vice grips are great for the easy extraction but my favourite is the fine blade high speed cutter cutting the slot for a flat blade screwdriver like Bear said.

 

Another is drill out as much of the broken fastener and use a tap to remove the remaining thread.

Heat gun on HOT is very useful but above all, patience.

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I find that a lot of Jap bolts are rubbish, I call them "play-doh" grade. The problem with that is they stretch a lot before breaking off, which locks them in the hole. Very shit to get out and Jap stuff is notoriously hard to get at too.

 

At the other end of the scale, you have Euro gear that generally has really high grade fasteners. If they do fail, it's often a clean break because harder steel is brittle. One example: Mercedes buses used to break sump bolts all the time, on 90% of them you could wind out the broken bit with the end of a scriber as they were 10.9 grade.

 

On a seized thread, heat is always my number 1 method, along with rapid cooling of the bolt with some kind of cutting lube or penetrating oil.

 

Extractors are good if you can get the drill in dead-centre and in line with the hole. If not, you may as well crack out the heli-coil kit as a matter of course.

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Cool idea....

 

Left handed drill bits work the best.

Ezy outs

Stud extractors

Weld a nut on top

Cut a slot with hacksaw, and use a screwdriver

2 nuts tightened together on the thread

 

You just listed my top 4 but I like...

sharp blow with a hammer can have similar effect

 

 

Is very good

 

Vice grips are great for the easy extraction but my favourite is the fine blade high speed cutter cutting the slot for a flat blade screwdriver like Bear said.

 

Another is drill out as much of the broken fastener and use a tap to remove the remaining thread.

 

 

Used them more than once if you can get a grip and swing, work it back and forth don'y try and turn it out in one go, keep it lubed and use some heeat if you have it.

Drill and tap is the best but ..

I find that a lot of Jap bolts are rubbish, I call them "play-doh" grade. The problem with that is they stretch a lot before breaking off, which locks them in the hole. Very shit to get out and Jap stuff is notoriously hard to get at too.

 

At the other end of the scale, you have Euro gear that generally has really high grade fasteners. If they do fail, it's often a clean break because harder steel is brittle. One example: Mercedes buses used to break sump bolts all the time, on 90% of them you could wind out the broken bit with the end of a scriber as they were 10.9 grade.

 

On a seized thread, heat is always my number 1 method, along with rapid cooling of the bolt with some kind of cutting lube or penetrating oil.

 

Extractors are good if you can get the drill in dead-centre and in line with the hole. If not, you may as well crack out the heli-coil kit as a matter of course.

Asians make components from high grade cheese so if it's a cheap and nasty then drill and tap, the bolt will dissolve under force.

 

But my favourite is the OXY and a hammer after drilling for an eazy-out then let it cool, some WD and heat it again (it will catch fire but only for a moment)

she'll move then. (try and get the blade boss from a 40year old rover mower and you'll learn a shit load about being stuck)

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