Snapped exhaust stud use flux core or wire with co2

  1. Tim007 Member

    Messages:
    19
    Location:
    Berkshire
    Hi All

    I hope you are staying safe and well!

    I have a little issue and I am hoping for some pointers with what I have a present on what I should do.

    So the machine I have a is a Sealey MightyMig100XT mk2 but I don't have any argon mix gas at present but I do have a co2 fire extinguisher set up that I could use with Sealey wire 0.6 or 0.8 wire or should I use some flux core 0.8?

    My project is a motorcycle ally head that has a snapped m6 steel exhaust stud that is about 5mm below the surface of the head so my plan was to build up some weld then weld on a washer to the built up weld, then a nut onto that, as from the looking around that seems to be the best option.

    So where my issues comes from is I have never used the machine in anger as yet and not sure what the best option is would it be better to either use so flux core wire or use normal normal wire and the co2 set up I have? Also any idea's on what sort of setting to use for this. Obviously I will clean up the parts to be welded is my 1st job but after that I need a bit of guidance.

    My idea situation would be take it to work and get one of the boys to weld it for me but with the current situation we have to use what we have to hand. Also I can then practice on a nut and bolt to get an idea of settings but any pointers would be great.

    Any help would be great Thanks Tim
     
  2. gordon stephenson

    gordon stephenson Forum Supporter

    Messages:
    6,806
    Location:
    Skelton in Cleveland U.K.
    I think that I would go for the drilling out route, less danger of catching or damageing the ally head,
     
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  3. Tim007 Member

    Messages:
    19
    Location:
    Berkshire
    Thanks for your response Gordon but that is not something I can do at home accurately especially as the bolt has sheared at an angle so the drill will most prob wander and I will end up damaging the head anyway. So would welding with co2 be easier than flux core for a new welder? it doesn't need to be pretty as long as it holds to turn the remains of the stud out that is all I need to worry about and god forbid I wreck the head I can get a 2nd hand one for circa £60 so it is not the end of the world if I do kill it.
     
  4. gordon stephenson

    gordon stephenson Forum Supporter

    Messages:
    6,806
    Location:
    Skelton in Cleveland U.K.
    Get a 6mm bolt cut off a short piece of the thread, Drill down its length in the centre, (have a few goes) to get t right, Then screw into the head to guide your pilot drill, go steady and you should have some success.
     
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  5. Fazerruss

    Fazerruss Member

    Messages:
    2,602
    West Yorkshire
    If the bolt has sheared off below the surface then I doubt a blob of weld in a hole will be strong enough to remove a seized stud and you are likely to melt the surrounding aluminium in to the weld .You are better off making a drilling jig around 15 mm thick to bolt on where the flanges were to guide the drill bit.
    I do these repairs quite often and from experience broken studs require a fair amount of torque to remove even after warming with oxy acetylene so I think the welded washer will just snap off even further down.
     
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  6. maz0

    maz0 Forum Supporter

    Messages:
    645
    Location:
    Central Scotland
    Got my hondas trx300 head in a vice just now both exhaust studs snapped above the hole. I tried welding them both several times, even trying a fancier method of welding a long blob on and shorting the bolt to the head with a car battery, which gets the bolt glowing. Didn’t even touch them, its as if they were part of the head its self. Just drilled them both out and the heli coil kit arrived today.

    Maybe save your self the bother, the weld trick is ok for a loose snapped bolt but not great for a seized snapped bolt.
     
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  7. eddie49 Member

    Tim, whereabouts in Royal Berkshire are you? I'm in RG6, have various welders, and a pillar drill.
    I could make the "drilled M6" guide that Gordon suggested.
    Could the location be drilled out and tapped for a new stud of the next size up - M8 ?
     
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  8. angellonewolf

    angellonewolf Member

    Messages:
    5,236
    Location:
    bristol england
    ive got one or 2 out with welding im a bit of a newbe to welding as your self but failed on more than ive removed so unless you know what your doing better take up the offer and give a beer tokens to have the job done saving 60 quid spend a bit to save a bit
     
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  9. Seadog

    Seadog Forum Supporter

    Messages:
    6,292
    Location:
    NE London - UK
    As it happens I've just come across a jig that I made around 2007. My 1997 Range Rover V8 stated blowing from the exhaust manifold. It turned out that there were two sheared studs and a stripped one. After a lot of contemplation driven by a marked reluctance to removing a head in the street, I came up with this beast. The centres were picked up from the manifold and drilled and tapped for 20mm stud. Then drilling bushes were made from a piece of stud. Centre pilot, root diameter and tap size bushes were made, hopefully to be able to pick out the remains or, at least, to guide a tap in squarely. Then two others for Helicoil drill size and Helicoil tap pilot size. It worked extremely well but I couldn't have done it without the use of a DeWalt angle drill and some drills that I cut down because of the limited space.

    20200429_193704[1].jpg
     
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  10. The way I do it (you need a pillar drill) put the new piece of threaded bar of suitable length (a set screw with the head cut off) into the chuck and clamp it in the vice, bolt the vice down to the table, release the threaded bar from the chuck. This obviously centres the job. Then drill a pilot size hole down the centre of the threaded bar and continue as above.

    It's easy when you know but if you don't it can save ages messing about trying to get the hole central.
     
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  11. Tim007 Member

    Messages:
    19
    Location:
    Berkshire
    I am only just down the road in Thatcham, so not a million miles away.
     
  12. Tim007 Member

    Messages:
    19
    Location:
    Berkshire
    I am trying to do some work at present lol but when I get a chance later I will take a couple of photo's. What has actually happened is to cause the issue my original bike engine keeps exploding clutches for some reason. If you are familiar with motor cycle wet clutches what is happening is the centre of the clutch basket keeps breaking up for some reason. I think there must be an issue with how it attached to the crank or something as I have put two new clutch baskets in now with two new pressure plates but I have come to the conclusion that that is a consequence of something else not being right and the cost of paying someone to strip it investigate the issue a new engine would be cheaper . So I brought a 2nd hand engine to put in the bike but when it turned up it had a snapped exhaust stud and some of them bent. So I was planning to swap the complete engine over as the cost of the gasket kit for the bike costs more than the engine did lol. I would take the head off my original bike and put it onto this 2nd hand engine but it already has a helicoil on one of the spark plug holes and it keeps misfiring due to a sticking valve (Not sure which one as when you look at them they all seem straight and true etc unless I use the mighty redex then it runs sweetly! So I thought getting the studs out of this head would be better but now it may not. So all the remaining studs seem to be seized, so for the last few days I have been soaking them in WD40 to try and help free them off before I get a butane torch on them to see if they come out. I have tried the double nut trick on a couple of the studs but ended up pulling the tread out of the lower nut(Cheap nuts lol). So unless I get get these other ones out it might be another 2nd hand head anyway.
     
  13. Fazerruss

    Fazerruss Member

    Messages:
    2,602
    West Yorkshire
    WD40 is crap. Use PlusGas formula A. And you could do with an oxy fuel torch as you need to get the studs red hot and they will come straight out.
     
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  14. Tim007 Member

    Messages:
    19
    Location:
    Berkshire
    Well after a few hours in the garage last night it was studs 1 and Tim 6, so I have managed to get out 6 in total but one just snapped clean off it was sadly on the same cylinder that the previous one was already gone. I think it will be a job for a machine shop once the madness is over! Forgot a photo before I started but the 1st picture was when I got the 1st two out. The remains of a stud under the oil feed pipe seems like a bit of threaded bar or maybe even a bolt that snapped all I know was it was so so tight in the thread. I heated it lubed it it did crack 1st movement but went solid again even after going back and forwards loads so heated it again lubed it and carried on like that it finally came out it was so noisy even after trying all sorts of lube I was waiting for it to snap at any point but came out in the end. Pic 1.jpg Pic 2.jpg Picture two was really a look at the original sheared bolt



    pic 3.jpg

    Finally as far as I have got 6 studs out, lubed them loads and cleaned them out then a bit of cutting oil and a tap down each thread the only one I had to work on was the part snapped stud I had to go back and forward a bit to clean out some crap but in the end turned out fine and now I can turn a M6 bolt all the way down each thread by hand till it bottoms out.

    So do we still think that would drill out at home as I am dubious that the drill would jump on the uneven surface my 1st estimation that it was 5mm under the surface was wrong they both are only 1mm so no room to get a centring thread in there to drill. May be easier to weld to now but what do you think?
     
  15. Seadog

    Seadog Forum Supporter

    Messages:
    6,292
    Location:
    NE London - UK
    Make something along the lines of my post No.9

    You've two clear stud holes to use to fix the plate in position. Use a centre drill to start, just pecking at the surface until you get it started, then finish with a drill at the stud ID. The thread should come out of the hole like a spring.
     
  16. Rusty

    Rusty Member

    Messages:
    595
    South West
    Get a centre punch with a decent point on it carefully mark the centre of the stud with the punch then gradually increase the size of the punch mark until you have a decent ‘lead in’ for a small sharp drill , carefully drill keeping it central , when you have drilled a decent depth into the stud use the next size up drill , when you have drilled out approximately 2/3 of the stud use a stud extractor ‘easy out’ type. WD40 isn’t much use for this type of job.
     
  17. bricol Member

    Messages:
    1,084
    N.Yorks, UK
    I assume you mean 2/3 the dia rather than 2/3 depth?

    I'd still stick with the suggestion above of drilling out to pilot size - when the 4mm hard brittle stud extactor snaps . . .
     
  18. Rusty

    Rusty Member

    Messages:
    595
    South West
    Yes 2/3 the diameter and as deep as you can.
     
  19. Tim007 Member

    Messages:
    19
    Location:
    Berkshire
    Well I bottled it lol All the gear and not enough of an idea!

    I took it to a local engine builders and they drilled them out for me they said I would never of got them out at home. They were well and truly stuck in there they ended up having to totally drill it out and put a full tread insert in both of them. He showed them to me, they are miles better than helicoils. You drill and tap like you would do with a helicoil but it has a funky tool that you use to put them in, and it flares the last few threads to anchor the insert in once it bottoms out in the tread.

    Quick picture of the inserts if you have not seen them before
    Inserts.jpg
    And now with new studs fitted!


    New studs.jpg

    Well I also checked valve clearances thank god they were all in tolerance as they are adjusted by shims "Old school" and I also swapped the intake manifold rubbers as they were well perished and a couple had cracks through to the inside so that would have well messed up the fuel to air mixture. Next step is to check the compression the best I can with a cold engine before fitting in the bike to see if it is any good!
     
  20. Ashley Burton

    Ashley Burton Member

    Messages:
    3,970
    Location:
    Northamptonhire
    Sounds like they used time -serts from what I can tell
     
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