I removed my exhaust yesterday. I'm pleased to say that when I fitted my Quat D 3 years ago I had the sense to copperslip the studs. The nuts were tight but they came off OK. I'm going to buy some new ones, clean the threads and re-grease when I fit the exhaust back. Are they M6 would anyone know?
hi, i had the same challenge trying to remove the front header pipe to remove the large OEM centre box / cat. Long story, one bolt remained in situ while the other two snapped . any thoughts how to rectify it?
To free stuck nuts I brush vigorously the available threads with a brash bristle brush then frequently applying diesel, (an excellent release agent due to its penetrating qualities), before trying with a metrinch socket which grips the nut on the flats rather than the corners. If still reluctant to budge then localised heat from an Oxy / Acetylene torch with a fine jet always does the trick. Occasionally the flange stud will come out with the nut which is even better as both can then be replaced. NOTE :- Re-assemble with copious amounts of Molyslip's Copaslip, or Comma's equivalent, and the nuts will still be removeable when the bike's in the tenure of your great, great great grandson !
I also use Diesel as a substitute for proprietary release sprays like WD40, as in most cases it's better because it leaves a better residue to lubricate the nut etc as it comes off. If you want to get Diesel to penetrate a bit easier you can dilute it down a bit to make it even thinner. Use something like Paint Thinner, Mineral Spirits or Turpentine. They have an evaporation rates in 10s of minutes rather than seconds or single figure minutes like Acetone, Meths or MEK. Thinning it with a fast acting Solvent won't give it a chance to get where it needs to whilst in a diluted state. Plasticine is also your friend in some situations. I always have some in the workshop to build a temporary Dam around stuck fasteners which you can fill with release agent to really soak it. It's also useful to finish the corners of temporary moulds for Epoxy or Polyester Resin(Fibreglass Laminating Resin) And if using Epoxy to repair parts a similar Dam can be used to stop it running away before setting.
Mig welding a new nut onto the sheared stud nearly always works with removal, as the heat generated by welding releases the stud in the head.
Exhaust studs ‘should’ be held by the bulge in the stud, not bottomed out on the head. This is good at this point! (And why you should never use threaded bar to make a new stud as it is then bottomed out in the hole). My first recommendation is repeated alternating heat from a mapp gas torch, cooling from a freezing spray, and your favourite brand of penetrating oil (plus-gas is mine) - repeat maybe 10 times. Then if it still goes wrong, you can’t kick yourself. Centre-punch the remains of the stud accurately (filing flat first if you can) drill a 3mm hole with a reverse thread drill in as a pilot, it may screw itself out at that point. If not, I have had good luck hammering in a quality torx socket (mine are old britool) until it is well in, maybe 10mm, then more heat and gently twist it out. If it strips, it was too seized anyway, and needs carefully drilling out. I would avoid stud extractors. Break one of those in there and you have a much bigger job on.
Diesel as mentioned is great, mix it 50:50 with paraffin and it’s even better. Tip I was given by a guy who worked on oil rigs where they get a shit ton of rusty stuff to deal with. Can also use it as a cutting oil for ally when milling or turning.
Nah. Just tried that on my stuck stud, and it just twisted off the protruding part further! Probably my poor welding ability.
Same for me, until I worked out that it's best to drop some weld onto the end of the stud before placing the nut and welding together.
