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View Full Version : Exhaust bolt broken off in Head

Aidan
21-09-08, 08:15 PM
Argh!
Trying to take the exhaust off my K3 I managed to break the head off the bolt going into the head of the engine. There is about 5mm of bolt left sticking out still. I would appreciate any suggestions as to how to go forward as I don't want to have to take the head off.

As the bolt is aluminium I'm not going to be able to weld a nut onto the thread (as I can't weld aluminium)

I have so far soaked what is left with Plusgas. My thoughts were to now get a source of heat (such as a one of those kitchen blowtorch things) and head the bit of bolt up, then attach mole grips and hope I can turn the remains of the nut.

Am I doing the right thing?:(
thefallenangel
21-09-08, 09:05 PM
should be able to as the allen bolts are easier to grip with grips. My advice is suzuki cheese might just crumble under heat but i'm not 100% sure.
yorkie_chris
21-09-08, 10:30 PM
Aluminium bolts? Are you sure about that?

Can you get a proper socket type stud extractor onto the remains?

If so then I've found that repeated heatings of the alloy while cooling the stud works. Stick a bit of potato over the stud.
northwind
22-09-08, 12:38 AM
If it really is an ally bolt, it'll be a piece of p to drill out.
zadar
22-09-08, 03:42 AM
stock bolts are steel.
Aidan
22-09-08, 08:14 AM
Aluminium bolts? Are you sure about that?


The bolt that did come out is non-magnetic. The bike I own has no exhaust modification and very grotty pipes - I can't believe the bolts aren't oem. I will certainly be looking around for stainless steel replacements.

I'm very wary about using a stud extractor - if it breaks in the head it will be a nightmare to get out. I think if the heat and mole grips don't work and just break off more of the thread then I will go for drilling and re-tapping.
Aidan
24-09-08, 07:09 AM
On second thoughts they were far too heavy to be alumnium. I didn't know you could have steel that wasn't magnetic:confused:
I managed to remove the sheared off bolt, but now need to replace it - any ideas of where I can buy 2 good quality allen bolts? (I know suzuki ones will be expensive and cr@p).
yorkie_chris
24-09-08, 11:03 AM
Allen bolts are a really bad idea. Get a stainless stud/cut down bolt and a flanged nut. Put it in with copperslip.
Stu
24-09-08, 11:08 AM
I managed to remove the sheared off bolt,
Well done!
I had the same problem & made it 100 times worse by trying a stud extractor which broke (as you forsaw).
So was it the method you said above, heat, plusgas & molegrips?