Broken Bolt Question

[Moko]

Ok so managed to get an hour to have a go at drilling out the bolt.

Managed to get through it but my hole is off centre....and the biggest problem if I chop down any larger drill bits they won't hold firmly in the drill chuck.

I've ordered a special short drill bit which hopefully will do the job but if you look at the photo it's only a couple of mm of bolt left in there so wondering if something like a milling bit on a Dremel might be a better option.

 

[Alex]

You''ve no chance with that now. Did yo not centre drill it first using the clamp as a guide?

 

[Moko]

No because the clamp is on the wrong side to allow any access for the drill.

If you see the photo below that's the only way it could be done without removing the exhaust headers which are blocking access from that side.

The only guide I had was the existing hole which I used.

 

[drmark]

Edited to delete my reply as way beyond my pay grade.
Good luck.

 

[KarlRS]

Broken bolt

Not going to say I told you so, there is still a chance to put it all back together and take it to the sepecialist. Or this is a bit left field but....
Try a coping saw, as you can thread the blade through then attach it, but I do not know if you can get blades to cut through Steel. If you can, incremental cuts taking care not cutting into the original thread. Perhaps if you make a number of cuts you may be able to use a very small punch to remove the bits of the bolt without damaging the original thread. I wish you every success, I really do. The one saving grace is if you opt for option 1 you can get the car back together and drive it there.

 

[Alex]

Would the clamp not have gone on on the reverse side? Anyway, that idea is gone now.

Capital idea getting a saw to do it. The blades you need are called Abrafiles (although hard to get hold of now but I think there are equivalents). They are like a thick wire that has cutting teeth in every direction. Use the hole through the bolt and cut into the remain part of the bolt until it breaks through to the ally. Once removed you have a chance the bolt may collapse in and you can poke it out. Might also get away with doing something similar with a round swiss file and filing the remains of the bolt out.

 

[KarlRS]

Broken bolt

One caveat to this. If going the DIY route with the saw and/or file. Take your time, you may well be able to succeed without damaging the threads which will save a whole load of grief. If you cannot get the suggested wire, you need blades at least 24TPi carbon steel. Buy cheap buy twice, get the best you can afford though I don't think they will break the bank. Keep us posted.[/i]

 

[GMG]

...good luck with this kiddo...good blades and take your time...get a strong pick so you can tease the remains of the bolt out... :thumbs:

 

[Sean-B]

There's a good chance on easy out will fetch that out

Random link to quickly show the tool

https://www.primetools.co.uk/product/bahco-1435-5-5-piece-screw-extractor-set-m4-m18-easy-out/

 

[Dinkler74]

Grab yourself a pencil die grinder and a left handed drill bit, slowly remove most of the bolt, leave enough for the drill bit to grab on to and it should come out easily. I have literally removed hundreds of bolts like this, the HGV techs i work with usually start with a half inch breaker bar on any size bolt and wonder why it snapped!

 

[Moko]

Managed another hour after work.....using a combination of screw extractor, small round file and pick to pull bits off I got this far.

From back of car towards the front the exhaust headers / heat shield there's not enough room for the tap and holder to turn freely enough to cut thread. I had just enough room to use a small screw extractor and holder.
But if I remove rear toe arm (from front of car towards back) there would be room for tap and holder to move evenly.

I ran the M4 tap loosely up the thread ( front of car towards the back using just hand pressure and there's plenty of thread in that end ).

So my big question now is have I removed enough of the existing bolt to attempt to rethread the hole?

 

[Dinkler74]

If the correct drill size, for the tap you are going to use, does not go through the hole then don't try tapping the hole. Removing a broken tap is way more hassle than a broken bolt. From the look of where you have got to, you could try filing two sections opposite each other, getting as close to the threads as possible, then take a sharp dot punch and try to knock each half of the bolt towards the centre, don't hit the dot punch down the side of the thread but across the hole, if the very top of the threaded hole is slightly damaged, your tap should rectify this. I have sometimes had to remove stubborn bolts/studs by removing as much material as possible, and pulled/picked out the remnants thread by thread.

 

[timbo1811]

Worst case scenario, could you drill out and use a nut and bolt?

 

[Moko]

Well I managed some more time on the bolt and amazingly with a combination of the pick and the M8 tap the remains of the bolt came out.

I then cleaned the threads up with a few runs through of the tap and refitted the sway bar and the bolt holds perfectly.

Thanks to all of you and especially DeMort / Iain for sharing your knowledge and encouragement when I felt lost, it just goes to prove if you keep trying you can succeed in the end.

I now have to book it in for an alignment and the complete arms / drop links replacement job will finally be finished.

 

[Parsley]

Sway bar.......mate don't :nooo: :grin: