[Mk2] [NA] Snapped off heads?

[TheDockter]

How have people gone about sorting snapped off bolts when repairing/swapping things?

I replaced a headlight motor today and all four bolts around the headlamp cover, where so corroded they just crumbled in the socket and snapped off, leaving the thread behind? Same with the motor brackets....

Do i just use a tiny drill bit, drill em out then replace? Is it that simple?

Thanks

[gerbil1028]

Small drill and stud extractors or just drill out increasing size each time.

When theres not much meat left I generally ram a flat blade screw driver in and spin it out.

[Peter Gidden]

Drill and taps.

2 hopes of stud extractor removing a sheared, rusted-in bolt. And bob's dead.

[ashley]

Try some form of centre punch to try and get an indent in the centre of the snapped off bolt, then slowly drill through as straight as possible with a bit that is just smaller than the inside of the thread...if you get it right you can normally peel out the remains of the thread from the bolt afterwards, clean it up with a tap and re-use in the same size

[fingers99]

There are various methods. I like a real penetrating oil (Plus Gas or GT-85, for example).

If that doesn't work and there is enough material sticking out I weld a bigger nut on. I've never known that method to fail (although sometimes the weld will fail -- just do it again). I put it down to the heat shock breaking the oxide bond -- the bigger, newer bolt just gives you a fastener which is easier to grip.

I've never known an extractor to work. The drilling and tapping way takes more time.

But I'd never go near a fastener which hasn't been shifted for 20 years or so without a penetrating oil.

[rs007]

Those stud extractors are nigh on useless - if a bolt is so siezed its head snaps off, then the stud extractor will just snap too - leaving a piece of hardened steel right there. Horrible things.

Careful drilling with quality bits and retapping - only way IMO