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Post by wmclaughlin on Jun 11, 2009 22:29:05 GMT 1
Hi Folks, I mentioned in a wanted thread that I needed an exhaust manifold clamp and that the old one was welded to the stud. Well, here's the evidence. You can see that there is about 1/4 inch of the stud left. I've tried vice grips on it but it won't budge. The question is, what do I need to disconnect (electrically) to mig weld a nut onto the broken stud? I reckon the heat of the weld alone should help free it. Thanks for any advice. Willie
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Post by McF on Jun 11, 2009 23:12:05 GMT 1
Hi willie that weld looked like a proper dog's breakfast I presume it was welded because the threaded part of the stud had already broken off and a previous owner couldn't get the old stud out.
If that is the case, it isn't a good sign!
My thoughts on isolating the electical system:
1. disconnect and remove the battery 2. disconnect the wires fron ignition pulse generators to CDI unit (a small four wire connector just inside the frame and quite close to the area you're going to weld. (Follow the wire from the front of the clutch housing, up the front part of the frame and you'll find the connector
Probably more than you need to do, but better safe than sorry.
I disagree that the heat from welding will help you. The heat will be directed into the stud, this may expand slightly and therefore grip tighter in the hole. When you have welded the nut on, I would allow it all to return to an even temperature before trying to shift the stud.
Returning to my initial logic before welding a nut onto the stud, is it worth cutting a slot across the stud and nut for a small piece of plate to key the nut to the stud? I think it is going to prove very troublesome and a bead of weld might not stand up to the effort. Make sure you don't end up turning the stud and taking a large piece of cylinder head with it.
Good luck and it you're able, take more pictures and report back with news of your success
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Post by oddjob1 on Jun 12, 2009 8:39:07 GMT 1
have had this before on another bike..i used a very small u bolt over the stud and adjustable spanner ...maybe not enough stud left to try it going by photo
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Post by wmclaughlin on Jun 12, 2009 9:25:51 GMT 1
Thanks for the replies, I'll disconnect the CDI just in case, this might be an expensive enough exercise without blowing it up. I like the idea of the slot although it might create a weak spot in an already weak stud. I might have enough room to weld behind the nut as well, mig wire should be thin enough to get behind the nut. I'll report any progress.
Willie
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Post by Buzzin (^_^) on Jun 12, 2009 11:23:15 GMT 1
I would recommend spraying lubricant first. Something like WD40, or other specific oils (I don't know the english word for 'kruipolie') It's meant especially to get stuck thing unstuck
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Post by McF on Jun 12, 2009 15:41:53 GMT 1
(I don't know the english word for 'kruipolie') Your English is always very good (usually a lot better than English people I know!) The literal translation of "kruip" is "creep" or "crawl", which does not help directly. I presume penetrating oil is what you refer to and I can then see how "creeping" or "crawling" would be used in Dutch. Penetrating oil is a very thin solution of graphite that can work it's way into many tight and awkward spots. Good suggestion, but I doubt it would work in this instance. The threaded hole goes "uphill", so anything applied in spray, or liquid, will run down the stud and away from the threaded hole. It might help if the cylinder head is removed. I may be a cynic, but I suspect that will probably be necessary, unless the weld holds strong enough to help get the reluctant little beggar out.
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Post by De Graaf van Salland on Jun 12, 2009 20:32:53 GMT 1
Hi Mcf,
I know that gravity pulls everything downwards, but there is something known as the "capillary effect" (in Dutch: de capillaire werking). I'm not quite sure that this is the right translation or even the right word for it.
But the effect is that any, very thin, fluid will creep upwards into any passage. As long as the passageway is also very narrow (i.e. only a few molecules wide).
So yes, penetration oil will move upwards. Allthough I agree that most of it will go downwards.
Franklin
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Post by McF on Jun 12, 2009 21:03:29 GMT 1
Hi Franklin the right word and a good explanation
I'm familiar with capillary action (and was a victim of it last Friday night when the bottoms of my shirt sleeves got soaked via my gloves filling up! (http://www.ntvhonda.proboards.com/index.cgi?board=general&action=display&thread=517)).
I think you're right, some penetrating oil will rise "uphill" via capillary action, but to get enough in there to make a difference will take a long time patiently applying lots and lots of penetrating oil, trying to catch it all running off the broken stud, while praying that a small amount is actually getting into the threads.
So here is a business opportunity - design and market a system that will clamp to a workface, around a seized in bolt or stud, that can then be pressurised to force penetrating oil into the threads and miraculously free it all up.
I've been talking to a Dutchman today called "Gerben", who praised me on my ability to pronounce his name (and surname) correctly second time I tried. - Well pleased!
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Post by wmclaughlin on Jun 14, 2009 20:04:23 GMT 1
Hi All, After spending six hours working on the bike, not all on the exhaust. I replaced the nasty front indicators with original slightly droopy ones and new headlamp brackets from pops (pictures later). I tried welding nuts onto the stud twice but with no success and then I remembered the suggestion of welding a piece of metal on. I welded a piece of 6mm flat bar on after grinding a notch to fit over the stud. Well the weld was good , unfortunately the stud broke about 1mm below the surface of the cylinder head. You can see the result. I turned a skim off a piece of 8mm alloy bar and centre drilled it. I was able to punch it into the stud hole enough to line it up and use it to guide a 2.5mm drill up the centre of the stud and then drilled it out to 6.5mm using progressively bigger drills. I then retapped the hole 8mm. Result below, with a nice new stainless stud. The stud is slightly out of alignment by abut 1mm at the end but saved lifting the head. I now have to get/make an exhaust clamp and put her together. Hopefully then I get her out for a run. Thanks for the advice. Willie.
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Post by McF on Jun 14, 2009 21:10:25 GMT 1
Pleased you have a result, and without damage to the head. Your heart must be in your mouth when the stud broke! Looks like a sound repair, did you consider replacing the other stud for the front exhaust? Good luck making up the bracket, please keep us posted with progress - hope your aNTy is roadworthy soon ;D
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Post by rj2para (Bisto) on Jun 14, 2009 21:25:12 GMT 1
respect, top job.
Hope she is back on the road soon.
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Post by Jaz66 on Jun 14, 2009 22:42:41 GMT 1
Hi willie... OMG what a mess you had to sort out.. Knew i was of no help so stayed out but was pretty confident that 'Those who know ' would be on the case to help you. Glad you are getting there, think for me that would have been scrapping time.. So respect for making and completing the attempt at repairing it.. As McF says "Keep us up to date with progress' and maybe real soon you'll get those toes back on the Tarmac.. ;D
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Post by wmclaughlin on Jun 21, 2009 17:04:23 GMT 1
Hi folks, Happily, this is the final instalment in the saga. I was able to fabricate a new exhaust clamp from a piece of 50X8mm steel bar I salvaged. The photo isn't very good but I recessed the clamp on the lathe to let it over the exhaust so that I could get enough of the nice new stainless dome nuts screwed on. Here you can see the completed job. The new clamp is overyly substantial and will certainly outlast the downpipe although it's hard to tell if the downpipe is stainless. Who cares, it works! I've had her out for a wee skite up the road and she's going well. The riding position seems quite high and she feels different from the Fazer but very enjoyable. All the best. Willie PS. If you're ever in the position of needing to drill out an exhaust stud, be careful cos you can drill into the water jacket. I was lucky and was able to get the stud to seal the hole.
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funk
Newbie
Posts: 4
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Post by funk on Jan 5, 2015 2:41:03 GMT 1
My stud crumbled away like dust when I went to take the exhaust off a few weeks back. It ended looking exactly like the OP's one - same side and all. I tried to get the stud out, used gas, pulled and twisted it but it didn't budge. I took the lazy mans way out in the end.
1. I made a new flange and disconnected the electrics
2. Put the exhaust back in place, slipped on the new flange and threaded a nut onto the good side just enough to keep it in place.
3. To hold the flange in place on the bad side so it could be welded, I put it in place, put pressure on it with an iron bar and clamped that bar to the frame.(having four hands helps)
4. Weld to the best of your ability.
5. Tighten up the good side and it was done:)
Said I'd post this as it might help someone. Maybe it's a common problem with the NTV. Excellent fix btw Willie. Found this thread when I was stuck trying to get the stud out of my own bike.
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