Removing stud from turbo

[jas915]

Changing my exhaust down pipe and one of the studs has snapped in the turbo, there is maybe only 3-5 mm sticking out so im guessing it will need drilling out. I've never drilled out a stud, how easy is it? i was hoping not to have to remove the turbo( are the studs harden steel, so hard to drill out). The alternative is remove the turbo and take it to a machine shop and get them to remove it.Are the bolts that hold the turbo to the manifold a use once type?
just wondering what you guys thought, on it a jx engine

thanks

[davegsm82]

When I sold my JX turbo I snapped 2x exhaust studs and 2x manifold bolts, a friend with a TIG welder welded nuts on to the remaining studs and they simply unscrewed after the heat of the TIG had worked its magic.

unfortunately this necessitates removal of the turbo but to be fair, you'd be best off removing it now, snapping all the bolts, then replacing the whole lot with good quality ones so it doesn't happen as readily in the future. I'm making a point of loosening and tightening the turbo bolts regularly on my AFN conversion for this exact reason.

Dave.

[carthago ian]

I replaced a blowing exhaust manifold on my JX , managed to snap a couple of bolts on the turbo plus 2 more on the cylinder head ; like you the bolts snapped off very close to the turbo , I bought cobalt drill bits and a set of taps , drilled out the studs and ran a tap thro to clean out the threads .
Started with 3.5 bit finished on 6.8mm . I used a cutting oil RTD Liquid to help , my aim is to tackle any task on my camper ... Just goes to show what can be done... I have never worked on any engine before I got my camper ... Hope this helps

[Mr Bean]

Probably teaching Granny to suck eggs but-
I have shifted many busted studs by welding a nut over them as the heat loosens the stud anyway but this can be tricky in an engine bay so if they have to be drilled:
The circle you see when you look at it - very visible if you file the top flat - is off the true center by the thread depth - think about it - so if you drill into the center of what you see your hole will not be concentric to the true axis of the stud. This may not matter all that much in many cases but when you try to pick out the thread remains or drill and tap for a helicoil it won't be dead center. I recently had this problem on the 1600 Frod Crossflow exhaust in my 60's classic speed boat and solved it by slipping a snug fitting tubular sleeve over the stud end and spotting the stud with a snug fitting drill to get a center. The pilot drill will then be concentric with the stud center. (I have a lathe and made a double diameter sleeve to fit both stud and pilot drill.)
Keep your pilot drill small in diameter so as to stop the final drill from pulling in too quick.
Plus if you are short of depth say with a waterway or oil channel to bust into make sure your drill chuck is tight and use a steel tube on the drill to control the depth.
OK Granny!
CS