Hi Guys, I have a bit of a problem and that is I snapped 3 bolts off the turbine housing. Has anyone on here had any success drilling out the holes and retapping them? If so what kind of drill bits should I looking at getting?? HSS? Cheers-

left hand drill bits are your friend.

Sometimes called easy-outs.

Easy out's would be the "easy" option here but it just won't happen as the turbine housing and the snapped off bolts are hardened steel not to mention the heat cycles that that housing/bolts go through over the years. Was thinking about getting a A/F tungsten carbide or cobalt drill set. Short of that I will have to find a place that will do it for me but if I do it myself I might learn something and get a decent set of drill bits out of it.

I got 4 out of mine using an easy out. Normal drill bit worked fine with it. Another option is to drill it right on centre and take it out to the size to suit an M8 tap and then run a tap through. Soaking with lots of yield, penetrene, inox, etc helps too

alright bought a set of drill bits and it didnt want to drill through. I was using lubricant to stop the bits from going blunt. Spent 3 hours on 1 hole and judging by how far it went in I'd say I have about 999,999 hours of drilling left and theres 4 bolts snapped!!! Going to call Garrett today to try and buy a brand new stock VLT turbine housing. That is unless sum1 here has an old one lying around that they want to sell me...

Drill at low speed on a drill press.. they will come out easy no need to buy a new housing. When you put new bolts in make sure you put some anti-seize on the threads.

Were they decent drill bits you bought?

Could try that stuff in a can what freezes the seized bolt and then try a chissel and hammer

Yea they were decent, they were cobalt drill bits and did the job really well. Now to tap some new threads...