Remove broken stud in thermostat housing

[Dave]

200TDI Defender engine. Removed 2 of the thermostat housing bolts which
were very stiff but the third sheared off. It's sticking out about 2 mm
from the top of the thermostat housing base. I've tried drilling it but
it is stubbornly resisting my drill bits. Cheap drill bits? Any advice
appreciated!

Many thanks,

Dave.

[Mark Solesbury]

Post by Dave
200TDI Defender engine. Removed 2 of the thermostat housing bolts which
were very stiff but the third sheared off. It's sticking out about 2 mm
from the top of the thermostat housing base. I've tried drilling it but
it is stubbornly resisting my drill bits. Cheap drill bits? Any advice
appreciated!
Many thanks,
Dave.

I once snapped a bolt off in the timing cover of my V8...

I then snapped a drill bit off in the whole that i drilled - cheap drill
bits are dirt!

I then bought a really expensive bit, with a special coating.

Nedless to say it pissed though the broken bit, and then though the
remaining stud.

Lesson learnt - dont snap bolts in timing cover, dont use cheap drill
bits on important parts!

[NoOne@Home]

Post by Mark Solesbury

Post by Dave
200TDI Defender engine. Removed 2 of the thermostat housing bolts which
were very stiff but the third sheared off. It's sticking out about 2 mm
from the top of the thermostat housing base. I've tried drilling it but
it is stubbornly resisting my drill bits. Cheap drill bits? Any advice
appreciated!
Many thanks,
Dave.

I once snapped a bolt off in the timing cover of my V8...
I then snapped a drill bit off in the whole that i drilled - cheap drill
bits are dirt!
I then bought a really expensive bit, with a special coating.
Nedless to say it pissed though the broken bit, and then though the
remaining stud.
Lesson learnt - dont snap bolts in timing cover, dont use cheap drill bits
on important parts!

Also buy a commercial quality "easy out", dont buy an el cheapo as you'll
end up having to drill the easy out as well.

[William Tasso]

On Tue, 08 Jul 2008 22:27:37 +0100, Mark Solesbury

Post by Mark Solesbury
...
I then bought a really expensive bit, with a special coating.
Nedless to say it pissed though the broken bit, and then though the
remaining stud.
Lesson learnt - dont snap bolts in timing cover, dont use cheap drill
bits on important parts!

<mantra>dont use cheap drill bits</mantra>

Life is too short for cheap tools - but I guess we all do on occasion

[EMB]

Post by Dave
200TDI Defender engine. Removed 2 of the thermostat housing bolts which
were very stiff but the third sheared off. It's sticking out about 2 mm
from the top of the thermostat housing base. I've tried drilling it but
it is stubbornly resisting my drill bits. Cheap drill bits? Any advice
appreciated!

MIG a nut to the remnants and use that to unwind it.

[AJH]

Post by Dave
I've tried drilling it but

Post by Dave
it is stubbornly resisting my drill bits. Cheap drill bits? Any advice
appreciated!

Tungsten burr?

AJH

[e***@gmail.com]

Possible approach.
Bolt the housing on with the two screws that came out.

Pick a drill that closely fits into the third hole at the broken
screw.
Drill enough to make a centered cone in the broken screw.

Then you might drill out the screw for a tap.
Or maybe drill for a helicoil insert.
If you drill for an extractor, use a freezing penetrant
to break the rust bond.
The screw is hard, so you need good drills and
a steady hand.

[Muddymike]

Post by e***@gmail.com
Possible approach.
Bolt the housing on with the two screws that came out.

I missed any earlier replies along with the original question on this. So
don't know if welding a nut or similar onto the remaining stump has been
suggested. See.
http://www.expertvillage.com/video/11073_mig-welding-remove-broken-stud.htm


Mike