snapped exhaust studs

[plugwit]

hi all.i have a dilema.whilst removeing the header pipes yesterday i snapped 3 of the 4 exhaust studs.there is about 10mm of thread on each stud still showing on the cylinder head.i have tried molegrips with no luck and there is not enough thread to do the 'double nut technique'.has anyone used a stud removal kit on exhaust studs and did it work.i'm worried about putting the removal tool in and it snapping inside the drilled stud.should i grind down the stud and then drill the whole stud out and the 'helicoil' some new threads.i have 4 brand new exhaust studs on the way to use as a depth reference so i dont pop the cylinder head.i think i know what i have to do but maybe someone has some old wives trick.........i have tried penatrating fluid aswell

[Jakey]

Try a decent quality easy out used correctly.
Heat and cold help also (blow torch and freeze spray used sensibly)
If the above fails, a drill and helicoil is due as you say.

Best to remember in future and take action to avoid the snap, heat and cold before attempting too loosen. And loads of penetrating fluid before trying

Good luck!

[plugwit]

Try a decent quality easy out used correctly.
Heat and cold help also (blow torch and freeze spray used sensibly)
If the above fails, a drill and helicoil is due as you say.

Best to remember in future and take action to avoid the snap, heat and cold before attempting too loosen. And loads of penetrating fluid before trying heat and cold?

Good luck!

heat and cold? when and how,both in the same extraction???

[Jakey]

Cool the stud and heat the head around the stud area. Breaks any corrosion and connection between the two.
Freeze spray you can buy and a small blow torch used carefully.
Try that to free up, then drill and use an easy out

[plugwit]

Cool the stud and heat the head around the stud area. Breaks any corrosion and connection between the two.
Freeze spray you can buy and a small blow torch used carefully.
Try that to free up, then drill and use an easy out

got some varuca freeze spray in the cupboard.that'll well do the trick.ha,my bikes got warts

[AlanH]

Try a decent quality easy out used correctly.
Heat and cold help also (blow torch and freeze spray used sensibly)
If the above fails, a drill and helicoil is due as you say.

If the above fails and an easy out snaps in the stud, your problem will then be trying to drill a hardened easy out rather than a relatively soft stud. Sometimes it's better to bite the bullet and drill the stud out but it's probably a job best left to someone who has a good amount of experience. Heads are a bit pricey and scarce.

I've had luck in the past tack welding a nut to the stud if there is enough protruding. This can be helped along by heating the head with oxy-acetylene and spraying plumbers freeze spray across the stud (not at the same time). It's a lot easier with the head off the motor but that's a big job in itself.

I hate poxy exhaust studs. It's my least favourite gotcha when working on a bike.

[Neal6677]

I did something similar a few years ago on a CBR600. Broke two out of eight.

Like AlanH tack I tack welded another nut on the end of the broken stud. Not easy with the engine still in the frame but that with some heat from a blow torch and gentle used of an impact driver got it moving. I would not reccommend drilling it out unless you take the engine out and bench mount it. Too much to go wrong.

Good luck.

[jasonbc]

I would just warm it up first, they are dis-similar metals so will expand and contract at different rates breaking any corrosion between the two materials then when they are still hot just work the stud forwards and backwards gently freeing it up slowly you can also try lagging it with penetrating oil over night and see if you get lucky. I wouldn't use easy-out until it becomes a last resort they are high carbon steel and you won't drill them out if it snaps and it will take for ever with a hammer and centre punch trying to chip a easy-out out of where ever it's stuck.
You could centre punch the centre of the stud and start with a very small drill and keep stepping it by 0.5mm at a time and as long as you get it started in the centre when you start getting close to the 6 or 8mm within 1/2 mm or (depending on the stud size) the last remaining bit normally comes out on the drill bit looking like a heli-coil. You want to do everything to avoid having to use helicoils aswell as they are only ever a temporary fix and never last that well.The possibilities are endless of how to do it just depends on luck and skill but mainly luck.

[Mervinh]

Easy outs are best out in the dustbin only use them on things that are already loose and you cannot get a grip on, trust me. all the rest is good advice