Advice wanted; removing a broken stud.

Discussion in 'UK Motorcycles' started by deadmail, May 29, 2006.

  1. deadmail

    deadmail Guest

    As subject really. Removing the exhaust from the K100 I've managed to
    snap one of the exhaust studs. Rather irritating because I was using a
    small ratchet to avoid putting too much pressure on but was short of
    time so hadn't heated the nut first. The irritating bit is I know it
    needn't have happened...

    However, regardless, it has.

    The K100 has the exhaust coming out of the bottom of the head about 14
    inches above the road so there isn't a lot of room.

    I've tried heat, plus gas and a stud extractor (socket type one that
    fits over the stud, not one you drill in and snap off...) I've also
    tried cutting a slot in the stud and using an impact driver.

    There's half an inch of stud left, my next thought was to put a nut on
    the stud and arc-weld the nut to the stud; after that it's head off and
    probably off to a shop.

    Anyone got any better ideas[1]?

    [1] Just **** off Lozzo, that doesn't help.
    deadmail, May 29, 2006
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  2. deadmail

    Andy Bonwick Guest

    Don't use heat unless you're using an oxy-acetylene set with a brazing
    nozzle. If you're using a normal blow torch you won't be able to put
    the heat straight onto the stud and nowhere else (1) so you'll waste
    your time and possibly even **** up other items as a side issue.

    I'd take off everything easily broken and then lay the bike on it's
    side on an old mattress so I could work on it easily then drill out
    the offending stud and if I'd fucked the threads throw in a helicoil.
    You know how to fit helicoils from a previous episode so it's not as
    if it'd be a monster job for you.

    I can't get hold of helicoil sets as easily as I used to be able to
    and I'm off to the IoM in a couple of days or I'd sort things out for
    you by using whatever we could get our hands on.

    Have a look at what the thread was before you started going farmer on
    it and let me know this morning. I've got quite a few metric taps and
    tapping drills in my van and I can put them in the post tomorrow

    (1) The head will expand in all directions as it warms up and the
    tapped hole will actually get smaller. This isn't really going to help
    is it? You need to get the stud to the point where it's glowing and
    that way it'll expand quicker than the head and then when it all cools
    down the threads should have lost whatever was seizing them up.
    Andy Bonwick, May 29, 2006
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  3. deadmail

    deadmail Guest

    Well, I don't have oxy-acetylene so the only option is a normal blow
    Hmm, possibly. Since it's done 110k miles I think the rings may need
    doing. I'll compression test the fucker and if it's low the head's
    coming off.
    It's an M8; fucking thing...

    And, thanks very much; address coming via email.
    So you don't think arc welding a nut on the stud's a good idea then?
    deadmail, May 29, 2006
  4. Using the patented Mavis Beacon "Hunt&Peck" Technique,
    If you want to borrow a left-handed drill bit, bung me an address and
    I'll put one in the post.

    It's an M8 thread you said?

    Wicked Uncle Nigel - Podium Placed Ducati Race Engineer

    SBS#39 OMF#6 Enfield 500 Curry House Racer "The Basmati Rice Burner",
    Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
    Suzuki TS250 "The Africa Single" Yamaha GTS1000
    Wicked Uncle Nigel, May 29, 2006
  5. FWIW, I do. Spray the stud with PlusGas or similar a few times beforehand
    and it should come out wivva nut welded on.

    Mungo \Two Sheds\ Toadfoot, May 29, 2006
  6. I've done this in the past, and it worked a treat.
    The Older Gentleman, May 29, 2006
  7. deadmail

    Andy Bonwick Guest

    In theory it should do the job but in practice it rarely works. I
    don't like welding anything on an engine unless I can put the return
    right next to where I'm welding so I wouldn't even consider it as an
    Andy Bonwick, May 29, 2006
  8. deadmail

    Andy Bonwick Guest

    Why do you think I chose it? I was hoping for a decent reaction but I
    suppose that'll arrive in the post after he gets the taps.
    Andy Bonwick, May 29, 2006
  9. deadmail

    Pip Guest

    I've never had much success doing this - even locking two nuts
    together and then welding them (more to get heat into the stud than
    anything else) - has usually resulted in the stud twisting off like
    elderly Brie.
    Pip, May 29, 2006
  10. deadmail

    Eiron Guest

    I found this to be the best method: Say to the man at your local head shop
    "While you're skimming it and grinding the valves, can you remove this broken
    stud as well please?" Especially after 110 thousand miles.
    Eiron, May 29, 2006
  11. deadmail

    Beav Guest

    The welded nut is the best idea. Use some "Easy out" spray type shit too,
    left for a couple of hours with liberal re-application.


    VN 750
    Zed 1000
    OMF# 19
    Beav, May 29, 2006
  12. deadmail

    Andy Bonwick Guest

    It's not the lack of success that puts me off, it's the potential for
    engine damage that does it for me.

    In my line of work we frequently have to weld machines down if we
    can't get decent clamps on them and doing this always fucks up the
    bearings in the machine spindle. This isn't a coincidence and
    obviously we're banging more amps through than you'd need to weld a
    nut on a stud but I still wouldn't do it.

    I don't always bother explaining why something isn't a good idea but
    Steve's a good bloke and has done me a lot of favours over the years
    so it's a pleasure to be able to help him if I can.
    Andy Bonwick, May 29, 2006
  13. deadmail

    deadmail Guest

    110k isn't much on a K series engine.

    The head won't be being skimmed and the valve grinding (if needed) will
    probably be done by me. I've done a pretty major rebuild on one K100
    engine and i think I'm lining myself up to consider another one at the
    deadmail, May 29, 2006
  14. deadmail

    deadmail Guest

    deadmail, May 29, 2006
  15. deadmail

    deadmail Guest

    Yes, I'm going to grind the thread off of the stud and force it into an
    M6 stud remover. It'll either snap or come out; I can't make it worse.

    If it snaps then I'll be in touch.

    deadmail, May 29, 2006
  16. deadmail

    Andy Bonwick Guest

    I've got an M8 tap, a 17/64" drill and a 4.5mm drill to use as a pilot
    waiting to be shoved into an envelope so they can wing their way to
    your home.

    I'd grind the remains of the stud flush with the head then
    if you're careful about lining up the pilot drill you should be able
    to use the pilot drill then the tapping drill and just be able to
    either pick out the remains of the stud or tap them out.
    Andy Bonwick, May 29, 2006
  17. deadmail

    deadmail Guest

    wrote in message

    Gotcha, you fucka.

    Ground it down so I could hammer a stud extractor over it[1]. Used some
    of that 'wurth' rost off snake oil .

    It came out easily enough this time. I suspect this means it won't get
    the heavy-duty engine rebuild now...!

    Thanks for the advice and offer of help.

    [1] like this, they work.

    [2] like this. Not convinced it did it or whether it was the plus gas
    I'd soaked it in overnight.
    deadmail, May 29, 2006
  18. deadmail

    deadmail Guest

    Well, to be honest I don't see it as an insult. I know farmers are some
    of the biggest bodgers out there; after all I cut my teeth helping my
    father bodge tractors, trailors, land rovers etc. etc.

    It was a nice phrase though.
    deadmail, May 29, 2006
  19. wrote
    Odd innit, all the advice given out for this problem always involves a
    bit of "apply liberally and walk away from it and leave it alone for a
    few hours before setting about the thing with a lump hammer" and it
    never ceases to amaze me how folks do just that while waiting for
    replies to questions and it *always* fucking works yet you never give
    credit for it.
    steve auvache, May 29, 2006
  20. Using the patented Mavis Beacon "Hunt&Peck" Technique,
    Fairy Nuff. I like the LH bits, every time I've used one the thread has
    spun out neatly before I've completely drilled it.

    Wicked Uncle Nigel - Podium Placed Ducati Race Engineer

    SBS#39 OMF#6 Enfield 500 Curry House Racer "The Basmati Rice Burner",
    Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
    Suzuki TS250 "The Africa Single" Yamaha GTS1000
    Wicked Uncle Nigel, May 29, 2006
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