Need help removing bolt

[bmw2002tiidriver]

I have a '72 tii. I bought a sanden compressor and a bracket from Dave. I went to put on the new bracket when I realized that one of the bolts from the old bracket was stuck in the block with no head on it. I tried getting it out with a screw extractor, but that didn't get me anywhere. Any other ideas?

[Catman]

Here is how I get it done.Center punch and start with 1/8" or so drill bit and work your way up until you are right at the edge.Pound in the extractor and slober it up with bolt blaster.( all of the bolts you are trying to loosen should be soaked over night with BOLT BLASTER.Squirt them often. jog the extracter back and forth in short bumping-jerky pushing and pulling ---- Then try to back it out.If that dont get it your best bet is to drill it out and put in a Heli-coil.I have a set for everything up to 1/2 inch.Indespensible on bolts frozen in aluminum.That oxidized aluminum crud and rust is like epoxy on a bolt.I have taken a small chisel and caught the edge of the shell left of the bolt and busted it out in pieces after you drill it.You have got to hit the center when you start or you will really tear up the hole. This is a chore that even the best mechanics struggle with.It takes patience and practice.( good drill bits-variable speed drill - skill !!!!!! and strong wrists.

Catman

[bmw2002tiidriver]

Well just tried again with a screw extractor. The tip of the extractor broke off... Anything to do about that?

[Mike87]

You might try welding a nut to the stub, then use a socket wrench to remove it. The heat from welding may loosen it a bit.

[Catman]

That pilot hole has to be drilled out as big as you can get so you can get the largest screw out in it. Take a small punch and tap the sides of the busted extractor and with a pic dig it out .You are on your way to haveing a melt down.Patience pay attention and dont force it.Like I said if it wont come out a helicoil is the only way to fix it.If it has a broken extractor stuck in it you wont be able to fix it.

[Guest Anonymous]

Heat helps. at some point you give up aqnd take it to a machine shop - they will get it out without having to resort to a helicoil.

[Catman]

Hey - the thing might even be cross threaded by whoever worked on it -and tightened down so hard they broke the head off. I have worked on them all in shops all over the place.Think about how that might have broken off.If it was loose it would have vibrated worn the bolt thru and the head fell off - but it would not have been so tight.Attack that thing. If you are experienced with a torch.Put the smallest brazing tip in it. Turned down as low as it can go.Heat the stub not the case.Heat until red -dull red -slap a soaking wet cold sponge or rag on it .Repeat may be 2 more times. It will come out or you will be drilling it out. That helicoil is stonger than the original hole. and will have nice clean sharpe threads.Many aluminum parts have them because they are stronger and more resistant to stripping out then the bare aluminum.and you would be done.

So endeth the lesson "

Catman

[ricortes]

Well just tried again with a screw extractor. The tip of the extractor broke off... Anything to do about that?

I might mention that I hate screw extractors with a passion. IMNSHO they are only meant for fresh bolts, like you are reassembling an engine and a bolt snaps while you are torquing it down. If a bolt snaps when you are trying to remove it, you are screwed. I've never had anything but your experience when trying to remove stuck bolts. It is like they make those screw extractors out of glass.

Take Mike's suggestion and try welding a nut on it. Put a washer underneath the nut to protect the block. Use something like WD40 or Liquid Wrench while the part is still hot so the oil gets sucked in as the weld cools. Don't spray it on while the weld is white hot of course.

I have always had better luck using an impact wrench or driver after the nut is welded on. The nut will lose its temper and the bead may not be much harder. An impact wrench set on its lowest setting and some patience works best.

If you want to keep trying to drill out the stud extractor, switch to left hand drill bits. I have had bolts come up just in the process of drilling them.

If you don't have a welder handy but you do have some exposed bolt, you can grind or file flats on either side. You should do some other work like heat, oil, and banging it with a hammer to loosen it up first but you may be able to get vise grips or a crescent wrench on it.

Rick

[Harv]

Snap-On sells reverse twist drill bits. They have been on my list of tools to get for a LONG time. My friend Jeff swears by em. usually by the second or third drilling the bolt usually comes right out. I have used them with great success.

John

[FB73tii]

I recall seeing a mechanic burn a snapped bolt out of a block with an oxy-acetylene cutting torch. Then just cleaned up threads with a tap. That was some time ago, so I might be wrong. Depends on relative melting point of metals involved.

Fred '74tii

[tbrduc]

one more tip that has worked for me.

if there's anything left of the stud/bolt, and you can get to it, use a chisel edge and tap the outer edge in reverse direction.

I have done this successfully, as long as there's something left to get a hold of.

[BDB]

Other advice i'd like to add based on changing and rebuilding all suspension parts on a rusty Wisconsin MBZ 300DT:

- heat and cool: heat with torch and then cool w/ a cooling spray. the expansion and contraction may aid in loosening any rust that might be binding the thread to the bolt

- using a pointed punch, tap on the remaining bolt. this may help break the rust bond.

- soak with PB blaster over night for a few days. when dry, heat and cool.

[bmw2002tiidriver]

It's not stuck in rust, I just can't get to it easily because it is slightly recessed into the block.

[TobyB]

I might mention that I hate screw extractors with a passion

you and me both... that said, I do have a few of them... so I know what I'm talking about!

t

[Arky2002]

Left hand drill bits are even available at Harbor Freight.

I broke a screw extractor off in a bolt in an aluminum head once. I was lucky enough to have enough room to drill 3 or 4 small holes around it and work it out. Turned a 1 hour job into an 8 hour job.