BIS EXHAUST Bolt / Stud snapped!

[ciaoflyer]

Removed my exhaust on the Bis and one of the bolts that holds it to the cylinder head has sheared leaving the rusty stud still in!

One of the bolts came out and is still operational, do you recommend repairing the one that has snapped or just tighten it with the one that remains?

If repair it means that the engine has to come out and I need a helicoil kit, where can I get one?

[gsxr126]

The lower rear stud on my A/C exhaust disappeared years ago - nut and all. No probs with any part of the exhaust to date.

Regardless of what you want to do, I would still try to remove the stud. Try welding a nut on the stud and unscrewing, rather than drilling it out which will need a helicoil.

[stuey]

if the exhaust is off just and some stud is visible clamp some grips on and wind it out then fit a new stud.

If you have to get a helicoil kit you can buy them on ebay for about £15

or take a roll up to kings lynn and I'll do it for you- some times getting the engine out is quicker and easier than try to do these jobs with it in...

[smallcox]

I would go for fixing it, you know these engines vibrate to hell .


Just to make it a little easier when I get a job like this I have a cup of tea. As the cyclinder head material is soft and the bolts are as hard as hell you can bet that when drilling the bit will wander straight to the softest material

If you are confident and tryed as above welding a nut to the stud with no susess. make a steel plate about 4 mm thick minimum and drill 2 holes in it of about 8 mm one hole and 5 mm the other at a pitch off the 2 studs in the head/manifold then bolt the plate in place. The 8mm hole can slide over the stud and held in place with a nut and line up the 5mm hole over the top off the stud to be drilled, this will stop the drill touching the aliminum and then run a 5mm drill down the broken stud all the way as the heat cutting may help to remove the stud with a easyout, failing this run a 6mm and then a 6.5 and finish with a 8mm tap to clear the threads. Some skill is needed but works for me

[Rusty's Uncle]

Easyout! OOOOOOOW 
Careful

[bis13]

dont forget with the helicoil kit you must get an odd sized drill bit to match the oversize tap dimensions,

[ciaoflyer]

Thought I would have to remove it!  Best to do these jobs properly.  Gonna try some moley grips on it first cos a fair bit of the stud is sticking out, will heating it help?

Thanks for replys guys!

[124cso]

Depending on how much stud is left showing, you could try a stud extractor. Koken or Sidchrome, Stahlwillie or Sykes Pickavent will all have them. They look like a figure 8 socket bit and lock onto the outside of the stud and self energise using a knurled cam wheel.
You could try penetrating fluid first but I personally doubt that it EVER actually works. If you can unwind the stud without pulling the alloy thread out with it ( it sometimes siezes to the stud stronger than it's own parent metal) you can simply run in a new stud without need of helicoils. Perhaps use a drop or 2 of locktite threadlock.
NB There are lots of different 'locktite' products and you need the right one for threads. Rocol make one too.

[smallcox]

If the stud is sticking out, weld a nut onto the stud then before it cools use a good fitting socket to undo it

[stuey]

As theses guys have said if you can go with heat penetrating fluid and either moleys or better yet if you can get to it a good stud remover. And be patient!

[124cso]

Re the penetrating fluids, as I said, I have never had any real success with them on old rusted stuff. A drop or two of Diesoline might work better if you have access to it ? It certainly finds any leaks in soldered tins that have previously held petrol for years !

[ciaoflyer]

Bought one of these.......

http://www.machinemart.co.uk/images/library/product/huge/04/040814951.jpg

Hope it works!

[jokke]

I will go for smallcox ide.. weld a nut on it.. it will come out as east as nothing.. 

[Kipster]

I had the same problem recently, i had to remove the cylinder head and the stud needed to be drilled . Stud extractors were a waste of time, at least i now know the job is done correctly.

[ciaoflyer]

Extractor did not work on stud in cylinder head, so I used an angle grinder to grind the edges of the stud and then removed it with an ajustable spanner....



The Extractor did come in handy for the two studs stuck in the exhaust mount plate......







Worked a treat so not a total waste of money!