Steel screw broken off in aluminium throttle body

[RobertSmalls]

The head broke off, and only ~3mm of threads are sticking out. I can't get vise grips on that. I tried a drill, but the drill just wants to walk.

What are my options for removing this broken fastener?

[SVOboy]

You could grind it flat, tap it with a nail, and try to get the drill started?

[wyatt]

This is the type of set that comes to mind... Screw-Out Set, SEARS Bolt-Out Set, SEARS although they might want to "walk" on you too if you don't use a punch to start the hole.

[Christ]

Yeah, whatever you do, you'll need to grind/file it.

Or, you could try to JB-weld another screw to it, that might work too, but not likely.

I personally suggest flat file, then center punch, then small forward drill, then extractor.

If it's large enough, you could also try filing a slot into it with a cut-off wheel, then using a screwdriver. However, if it's in there tight enough that it broke off, a screwdriver will probably just strip the new slot out.

[dcb]

cut a slot w/a dremel in it and put a big screwdriver to it?

[Christ]

Hm... Apparently, my edit didn't save.

I had also suggested what dcb said.

[user removed]

Done a few hundred of those. I doubt if a screwdriver will do you any good.

Best bet is to center punch the shaft of the screw and drill through it. You will need a good cobalt bit.

Also probably need a easy out. Some of them are straight and you can actually get the screw to go in a small amount, like a 1/4 turn. Then back it out a little and run it back in a little to break the bond.

Be real patient and you might save the threads, some penetrating oil will also help.

Used to have to do a lot of them on broken manifold studs on the old in line 6 Nissan Z car engines. If you can't get it out measure the diameter of the screw you got out and use a drill bit just slightly smaller than that diameter. Sometimes this will allow you to get the rest of the threads out of the part you don't want to damage.

If not then you will have to use a helicoil.

regards
Mech

[TempoRacer]

Get a mig weldder and weld a nice big nipple of steel on the end of it then use some vise grips to take it off if vise grips don't work weld a nut on your weldded steel nipple then just use a socket and voila it out. I do over 20 a week in A Midas Muffler shop I'M a pro at it . so I know what to do. any question just ask.

[Johnny Mullet]

If there is still some extruding out, they make really nice extractors that will grab and remove the stud.

[RobertSmalls]

I ground it flat with a dremel, then tried to center-punch it with a nail. Not a chance. It blunted my best nails.

That's the point when I gave up, and replaced the throttle body as a unit. I was avoiding that because I didn't want to break the throttle cable adjustment screw. No worries there, because that screw is brass.

Job's done, Insight's got an IACV now.

I had to steal screws off my bicycle because I didn't have any other M5x0.9 bolts that were long enough.