Broken Bolts - AHHHHHHH

theycallmeWALLY

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So yesterday when pulling the trans out of the Ranger I had 3 seized up bolts that hold the Y-Pipe of the exhaust in place.

Ended up cutting the bolts and then proceeded to drill them out. I had brand new drill bits and I'm pretty sure I burnt up a few in the process. I tried to go slow use a bunch of cutting oil but it took me like 2 solid hours to get all 3 drilled out.

What I did and please tell me what you would have done differently...

  1. Drill small pilot hole all the way through the bolt.
    1. This drilled through the fasted.
  2. Then drilled out with a drill bit 3 times the size and continued this process until I was at 7/16
  3. I tried mixing in some step drill bits but they didn't do $hit
The larger the drill bits got and closer to the OD of the bolts the harder the bolts got and basically the drill bits were getting super hot very fast.

#Trucksaredumb
 
Couldn’t weld a nut on it?
Maybe I worded the title slightly incorrect.

They were seized up in there and I didn't actually break the bolt before cutting them off.

I was hesitant about welding a nut onto the cut bolt because I assumed it'd just make the material even that much harder to drill through if I wasn't able to get it loose.
 
Maybe I worded the title slightly incorrect.

They were seized up in there and I didn't actually break the bolt before cutting them off.

I was hesitant about welding a nut onto the cut bolt because I assumed it'd just make the material even that much harder to drill through if I wasn't able to get it loose.
Ah that makes sense. Usually the heat and contracting is enough to break them free, though
 
If a tig was available, I'd probably use it to heat and the soak with some penetrating fluid. Or weld a bigger nut on the end for the same effect and use a bigger wrench.
 
If a tig was available, I'd probably use it to heat and the soak with some penetrating fluid. Or weld a bigger nut on the end for the same effect and use a bigger wrench.
I had sprayed it probably 4 times over a 12 hour period with penetrating fluid. Then the next morning I went out and bought a small torch that I could fit in there without catching the truck on fire. torched it for like 5 min and was also cranking on it with the impact gun. Didn't budge.

I'm guessing a tig would have gotten it all a lot hotter though.
 
i would have used alot of heat before just cutting/drilling. some mapp gas set onto the bolt for a good long while and then see if it cracks loose. if it does, turn till it gets harder to turn, then crank back in some and apply more heat.

HSS drill bits dont like cutting harden bolts. sounds like they may have been 10.9 or grade 8? a carbide drill bit would have probably worked better once you got to the bigger sizes.
 
i would have used alot of heat before just cutting/drilling. some mapp gas set onto the bolt for a good long while and then see if it cracks loose. if it does, turn till it gets harder to turn, then crank back in some and apply more heat.

HSS drill bits dont like cutting harden bolts. sounds like they may have been 10.9 or grade 8? a carbide drill bit would have probably worked better once you got to the bigger sizes.
See comment above.
 
I had sprayed it probably 4 times over a 12 hour period with penetrating fluid. Then the next morning I went out and bought a small torch that I could fit in there without catching the truck on fire. torched it for like 5 min and was also cranking on it with the impact gun. Didn't budge.

I'm guessing a tig would have gotten it all a lot hotter though.
man id have left it longer. ive had times where ive left the mapp gas on for 10-15 min and got shit smoking hot. ideally red hot
 
Copy. Maybe If i wasn't laying on my back with my arms up I would have left it longer haha. Lessen learned.
agreed. a oxy/acetalene torch would be the best thing but not everyone has one lol.

i have not tried this but ive been told heating the heck out of the bolt and then spraying it down with penetrating oil helps shock the rust loose and the oil to get into the threads better.
 
what drill bits were you using? i bought a nice set a year or two back and couldnt believe how much nicer they cut then the standard crap i was buying at home depot.
 
seems like those should be good...
this is what i bought and have been happy... I am sure someone like brian knows more about whats good then me.

 
I always weld a nut into broken bolts then when hot spray some wd40 and they almost always unscrew since the heat and wd40 get in there and break the rust loose. Had to do that numerous times over the years and even on broken exhaust studs too but those are into aluminum heads so the weld and heat allow those to break loose easily.
 
Geoff nailed it.

Some say tack a washer to the broken bolt first, then the nut on top of the washer. I don't do that, but it works for a friend.

Another tip is be patience with the cooling process, attack the bolt with a cheater bar or impact wrench too soon and the nut just peals right off the broken bolt you are trying to extract, no good. I like to spray a little penetrating oil on bolt while it's cooling for three reasons, I like the smell, it makes a bunch of smoke which looks cool and I feel like the penetrating oil can soak in better when the work is hot.

Last tip, if at first you don't succeed, try again and again, do this enough times and the heat and cooling cycles will unstick just about any froxzen or galled up bolt. Plus welding is way more enjoyable than trying to drill and extract a broken bolt, every mechanics nightmare.
 
Also a tip I've done a few times if you break a tap off in a hole. Canned duster air turned upside down will "freeze" the tap so then a center punch will break it easier so then you can remove pieces and try again.
 
most folks pretty much covered everything I would do so the only thing I have to add is maybe consider watching a few tool restoration videos on youtube.
Those dudes take some of the most rotten & rusty pieces of machinery and make them new, and in a lot of cases they're dealing with some very stubborn hardware. Maybe some tricks in there to pick up.

one dude has an "impact" screwdriver - meaning this thing is a screwdriver that you smack with a hammer and each hammer blow transfers to a rotation simultaneously. Likely not helpful for this specific problem but maybe good for the future
 
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