Broken 8 mm. bolt heat shield exhaust

[Azur]

Hi,

Just putting an extra washer between a bolt to secure the heat shield resulted in yet another lot of frustration today. Despite using various (expensive) remedies, buying super crude oil WD40, hammering, tapping, de-rusting etc, the head of the bolt broke off. Off to the hardware store to buy special studs to drill into the bolt. Problem is that lying under the car I can't drill a hole in the bolt, all the drill bits break off and it's no good like this. Does anyone know another method? Glue the bolt head back with locktite or will that not work? I can not imagine it would be strong enough.

Thanks,

Emiel

[Matt_75]

I don't think loctite will have the strength. Welding a nut onto the bolt is normally the go to, the heat generated also helps loosen the bolt. Obviously this requires a welder.

I've also had success with drilling a hole in the bolt and using an extractor set. These are the drill bits I have: https://amzn.eu/d/hjEoWB8

And the extractors: https://www.ebay.co.uk/itm/251851692...mis&media=COPY

[trikey]

You will have to drill it out emiel if you want to do the job properly, otherwise a small screw in another part of the floor to hold the shield in place.

Sent from my SM-G780G using Tapatalk

[macafee2]

Is any thread showing?
Warning, the things you insert into a bolt to remove it, can snap.
Have you tried heating the bolt. If you do not want to use a flame, try an electric paint stripper.

macafee2

[Rover04]

Firstly, if you are breaking drill bits then you are exerting too much pressure or drilling at and angle and bending the bits. Use good quality cobalt or Cobalt G drills, slow speed, starting with a very sharp 2 or 3mm drill and working up, use a luburicating oil if you can, after you have started the hole with a small drill go up in sizes until the hole is big enough to insert an extractor then tap one in and hope for the best! If the extractor does not work, or worse it breaks then you have to think about other methods. You could drill out until you remove all the bolt, then re-thread or use Heli-coils, or step up to a bigger thread (it is probably 6mm and you could go upt ot 7 or 8). If the extractor breaks you are in a world of pain as most drills will not touch the remnants, a dremel with a grinding bit is your friend here!

[Martin Butler]

if you can safely do it WD40 and a blow torch, if theres enough thread wind a nut onto it, soak in WD40, ( or similar) and warm up with the blow torch, till cherry red tap it wit a hammer, and try to turn the nut, to wind the thread out, Keep heating and using wd40, it should do the trick

[macafee2]

Originally Posted by Martin Butler

if you can safely do it WD40 and a blow torch, if theres enough thread wind a nut onto it, soak in WD40, ( or similar) and warm up with the blow torch, till cherry red tap it wit a hammer, and try to turn the nut, to wind the thread out, Keep heating and using wd40, it should do the trick

Which way is the nut to be turned? Anti Clockswise, wont it come off? Clockwise wont it tighten?

macafee2

[Arctic]

Hi Emiel.
save your self a lot of work and maybe unsuccessful drilling etc, drill a 5/6mm hole into the chassis next to the original bolt, and use a self tapping bolt.

[Ducati750cc]

Originally Posted by Arctic

Hi Emiel.
save your self a lot of work and maybe unsuccessful drilling etc, drill a 5/6mm hole into the chassis next to the original bolt, and use a self tapping bolt.

Beat me to it

[Azur]

Good morning everyone, thank you all for your kind replies and tips and tricks. It is appreciated and gives me a boost to tackle this little but annoying leftover bolt! I have not heated it yet and there is no thread left. Normally I think I would go for the option of drilling the bolt completely out and tap a new thread into it, but now I will take the advice using a screw or to drill a new hole into the chassis and use a self tapping bolt. That should save a lot of time and effort now. Where would the cars be without you all. Whished the thanks button would be here!