Hi, this happened to me too, all I can say is don't try to get it out with an easy out, I ended up breaking the casting.
image url upload On the plus side ( well I assume it makes it slightly easier) the other end of the bolt is accesible
If they're M8s (likely are), could drill hole out maybe 8.5mm, and put a bolt/nut right through it. Or could helicoil the hole after drilling the bolt out.
I would drill it out. Start with a 3mm drill bit and get the hole dead centre. Go up in drill bit size a mm at a time. I find that before you get to the size of the stud, the broken stub will unscrew itself out the back. Did this recently with 4 drive shaft broken studs/bolts. Just clean the threads with a tap afterwards.
Grr almost through with first drill bit and bleeding snapped off. Am I right in thinking I now need a carbide bit to drill out the cobalt bit? Or is there another way?
No it's snapped off below surface , managed to drill down a bit with a bigger drill but now it's hit the snapped one it's going nowhere. It was going so well ......
Could but it's a bit awkward as the housing is in the way of the drill a bit so may end up going in at an angle.
That is a bummer. As Mark suggested, see if you can get a pair of needle nosed pliers into the flutes of the drill bit to unwind it. There's not much holding it in. Failing that, I'd seriously suggest finding a friendly local machine shop. They can clamp it up in a milling machine and take it out with an end mill. If they do it 9mm or so, you can helicoil the hole.
Tweezers, go and buy a pack of cheap Draper pliers and file down the tips.. try lots of implements to get a grip.. You can possibly also smash the hard drill with the correct punch.
Bummer @volkswombat . That sounds like one of my days at work!! Going well, until it’s not!! I was in Southampton yesterday, you could have sorted my leaking steering box too @snotty and @volkswombat . Especially now that you’ve practiced on yours first!
No the snapped end is right inside , only way it's coming out is with drilling or machining ,, I don't want to do any more to it and risk ruining it so I'll do what snotty said and find an engineers to do it. There's an engine machining shop not far away I'll give them a try.
Ah well. It was worth having a go. See if the machine shop can preserve the old thread, if not it's the helicoil route as Snotty said.
What's annoying is that the cover/seal wasn't even leaking but I thought I'd do it anyway.......that'll learn me.
Research seems to point at Vinegar to dissolve rust slowly. Heat cycling with metal in freezer and boiling water. Penetrating oil on hot dry metal. Try using a centre punch off centre to drive it out from the back... Mind you if you take it to an engineering shop they can mill out the bushing if it has worn.
Do that, Jez. You'll likely knacker it more trying other stuff - there's not much meat on that casting. Any old-school machine shop should be able to machine it out - they're used to dealing with busted bolts and studs. May even be able to helicoil it for you - it'll be as good as new