Welding to header bolt. Safety pointers needed

[BigD_83]

This might seem like an obvious question, but when welding onto broken header bolts, what are the best practices for safety? (assume this is being done by MIG)

The BIG ONE (I would think): Remove the tank and place it a safe distance away

Is it necessary to drain the carbs and turn the engine a few times to displace any residual fumes/condensed fuel in the cylinders?

Anything else?

Thanks in advance.

[7981GS]

Remove or disconnect the battery.

Daniel

[1_v8_merc]

Just remove the battery, that's it.

You don't need to worry about the Carbs or Tank unless it's leaking or in your way.
You're only spot-welding the bolts so it'll only be about a 2 second blast, right?

Are you actually running Mig or Flux?

[BigD_83]

Just remove the battery, that's it.

You don't need to worry about the Carbs or Tank unless it's leaking or in your way.
You're only spot-welding the bolts so it'll only be about a 2 second blast, right?

Are you actually running Mig or Flux?

Good point about the battery. Might have overlooked that on my own. Thanks guys.

I'm hoping I'll be able to get my hands on a true MIG setup...from what I've been reading, I don't think I'm interested in flux. Doesn't seem to be the most utilitarian of the setups.

Of course, at this point I will be relying on the skills and equipment of others, so in the end it may be flux.

[7981GS]

If you think that jump-starting your bike with a running car can hurt it,
try welding on it.

Daniel

[chuck hahn]

remove the battery and if your worried about it, the gas tank too. Weld the nut on the stud pretty good and let it cool before trying to turn it so the weld hardens. You can drip some oil on the stud also just after youve welded. The heat will draw the oil up into the hole a little.

[Normk]

No need to disconnect the battery unless the battery is near the area to be welded and yu have concerns regarding gassing. I assume that you are electric welding? Arc, MIG, TIG?

Welding, welding related induction, etc. will not affect the battery. People often seek to protect the electronics components in the system by disconnecting the battery but any reflection will reveal that this is counter-productive. Removing the battery from the system removes an active damper across the circuit and so will tend to increase the effect of induction currents and voltage spikes.

Should someone wish to reduce concerns regarding electric welding and other induction issues, IMO, one is better advised to disconnect both cables from the battery and to connect these cables together as this will prevent a difference in potential from being created between ground and "hot" sides of the circuits.

The suggestion regardin dripping oil onto the hot stud is well taken. An even more effective technique can be to melt wax onto the hot stud allowing the wax to wick back up the threads. I prefer a motor oil or automatic transmission fluid for the purpose of lubricating threads to the use of light oil products such as WD40. Light oil products may penetrate up the threads more effectively when dealing with cold materials but lack the extreme pressure additives and tend to evaporate too quickly on hot areas.

One might also be wise to consider the effects of the smoke and other gasses emitted by oils and other products being exposed to high temperatures.....

[Octain]

I hear talk of welding a nut to a broken stud but I have never heard (or seen)of anyone being successful at it.
My welding skills leave a lot to be disired so maybe this is why it didnt work for me.

[chuck hahn]

Todd..If theres enough of the stud sticking out you start in the center of the stud and work the puddle outward till it welds to the nut. Once its cooled abit and the weld is hardened then a socket or wrench can be used. Ive done it and ive had the weld release too. Its a 50/50 gamble but if it holds then its the easiest way. Ive had to drill down the center of studs and go progressively larger so i could collapse the stud into itelf to get them out too. The job just sucks no matter what.

[Jedz123]

I had to weld custom brackets onto my B-12 for my highway pegs... Never removed anything, the area around the frame I was welding got very hot but other then that it was fine... That was 20K miles ago, last season.

[BigD_83]

Todd..If theres enough of the stud sticking out you start in the center of the stud and work the puddle outward till it welds to the nut. Once its cooled abit and the weld is hardened then a socket or wrench can be used. Ive done it and ive had the weld release too. Its a 50/50 gamble but if it holds then its the easiest way. Ive had to drill down the center of studs and go progressively larger so i could collapse the stud into itelf to get them out too. The job just sucks no matter what.

In my case there is not much of the stud sticking out. In fact, I'm not sure I have the requisite skill set to do this on my own right now. A PO butchered a previous extraction attempt, and it is not pretty...you can see in the (albeit blurry) second photo that there is only one stud/bolt with much relief at all.

[Planecrazy]

Your first issue here is to get the rust off the remaining studs before you attempt any welding at all. Otherwise the welds won't hold.

Second, you may want to leave those to a pro, because the heat required to make even a moderately effective weld will likely melt the surrounding aluminum, and then you're really screwed.

The biggest problem is that the P.O. mangled them up so badly trying to get them out in the first place. That attempt has left them without the material available to take the heat of the weld and actually fuse the nut on effectively. The off-center drill holes are particularly problematic in terms of avoiding aluminum melt.

Good luck with it, but quite frankly I'd pay a pro to avoid a larger bill later. I have MIG and am all about "doing it oneself," but I'd surely have second thoughts if I were faced with trying to weld on those studs...

Regards,

[blowerbike]

not to be negative but....
your done.
to fix it right you need to remove the head and take it to a machine shop and have those removed...end mill in a bridge-port thing.
i'm not just saying to fix it but to fix it right....

[blowerbike]

and just to add this...
anyone wanting to remove the exhaust bolts in the future...
run your engine and get it really HOT HOT.
this betters your chances.
penetrating oils and such does nothing for steel thats seized in aluminum.
the HEAT is the trick.

[BigD_83]

not to be negative but....
your done.
to fix it right you need to remove the head and take it to a machine shop and have those removed...end mill in a bridge-port thing.
i'm not just saying to fix it but to fix it right....

BB,

I do not disagree with you. My first thought when I looked at it was that there was a chance. The more I think about what is there, the more I think the most cost-effective solution is to take it to someone with the skills and experience to do the work with the engine (or head) out of the bike. I've been casting about for a replacement head, just in case things go south...

At the moment the bike can be ridden with the exhaust as is, but for the long-term health of the bike and my own peace of mind, it needs to be fixed. Even with access to the equipment at work, I do not have the experience to do it without turning the bad into something worse.

I've got a few inquiries out there locally to get quotes on the work, and there is another GSer with a certain skill set who is willing to have a look at it for me, if I can get the bike/engine to him.