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      05-25-2014, 10:51 PM   #1
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Busted bolt for sway bar - What to do?

Well, I replaced my thermostat and water pump. Everything went well BUT one important thing. When reinstalling my sway bar, I used my newly purchased torque wrench. Now either this thing is defective or its poorly built. I now know I should have tested it first. Long story short, I couldn't hear or feel a click and I over-torqued a nut on my front sway bar. The result? I broke 1 mounting bolt so now there's only 3 connections keeping my front sway bar in place. I now need a new bolt welded on or something to that result.

For reference, I snapped off a bolt holding the "03 stabilizer support" in the first image. It attaches to the subframe just above "11" in the second image.

My best guess is to find a local shop and weld a new bolt in place. Any recommendations on a shop near/around Sacramento/NorCal?

Or, any other suggestions?!

Thanks in advance!
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      05-26-2014, 10:15 AM   #2
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From what I recall, you should be able to: use a cutouff wheel to get the bolt flush, drill the head out, then use a replacement nut/bolt in it's place.
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      05-26-2014, 06:41 PM   #3
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try taking the bracket off and see if you can get some vice grips on the grip. there should not be much torque on it unless you have bottomed the threads out(unlikely). if it is too short to grip with vice grips. try looking on the other side and seeing how much thread is showing through. you might be able to gingerly turn the bolt enough to grip it from the other(lower)side.

another little trick is to use a sharp punch and start a little burr along the edge of face of the broken bolt, then tap the bolt in the direction to loosen.

but if all this fails, try an E-Z out.

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      05-26-2014, 10:20 PM   #4
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Have you seen the connection point in question? It's more of a stud than a bolt; similar to what stock downpipes have at the midpipe connection point. Given that, I doubt your suggestions would help much.
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      05-27-2014, 12:48 AM   #5
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Quote:
Originally Posted by FCobra94 View Post
From what I recall, you should be able to: use a cutouff wheel to get the bolt flush, drill the head out, then use a replacement nut/bolt in it's place.



yes, you are correct. it is not a BOLT at all. I was confused. too many sway bar swaps! the nomenclature had me confused.

but a steel stud should be able to be extracted.



I really don't think you can just drill a stud out and put a new bolt in. and using a nut and bolt is... a little... unfinished. it will require either a stud extraction or very precise drilling and cleaning up of the threads. if the stud threads into the aluminum subframe, then the issue becomes much more difficult if you are going to drill out the stud and clean the threads.

if the stud is threaded into the subframe(just like studs are threaded into, say, an engine block), then you should be able to extract the stud and replace it with a new one. heat, extraction tools and drills become your friends. as well as elbow grease and cursing

regardless, good luck... I just finished changing the exhaust manifold on an old ford 390 while in situ... and yes, the two hardest to reach bolts(yes, bolts) snapped. removal procedure is very similar to stud extraction. and yes, it involved much cursing.
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      05-27-2014, 01:32 AM   #6
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You guys are right. I guess it would be called a "stud" versus a "bolt". At this point, I could grind it down. Once flush, maybe someone could weld a new stud on?! But that would require me to drive somewhere and have the work done. Not opposed to it but if I can find a solution in my garage, I'd rather do that.

Now, I also thought I could grind it down and drill it out. Then replace with a bolt and nut. But, that poses another problem, I don't think the top of the subframe is accessible. So, would a self tapping machine bolt from the bottom into the subframe work?! I'm at a loss. This is annoying.
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      05-27-2014, 01:48 AM   #7
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I would be hesitant to use a self tapping bolt into aluminum.

If there is enough thickness, then maybe a thread repair kit... Helicoil or an insert. Or perhaps a rivnut type of fastener. can you determine what is holding the existing stud in? That might dictate your easiest solution.
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      05-27-2014, 03:00 AM   #8
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Would it be possible to drill out the stud and tap it? If the metal is thick enough.
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      05-27-2014, 03:15 AM   #9
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Found a picture for reference.... Unsure of the exact thickness but you can see how thick the subframe is elsewhere. Almost certain I can't get to the top of the subframe.
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      05-27-2014, 09:11 AM   #10
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hmmm. that bit the sway bar attaches to is not really that thick... I suspect there must be either a backing plate or perhaps some type of fastener used to anchor the studs.

do you have a small mirror and able to look behind that plate?

are you not driving you car in the meantime? I would think you could remove an endlink and drive around slowly for awhile.

hopefully someone here is going to do an oil change soon and can peek behind there with a small mirror!
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      05-27-2014, 09:41 AM   #11
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Quote:
Originally Posted by avocet
hmmm. that bit the sway bar attaches to is not really that thick... I suspect there must be either a backing plate or perhaps some type of fastener used to anchor the studs.

do you have a small mirror and able to look behind that plate?

are you not driving you car in the meantime? I would think you could remove an endlink and drive around slowly for awhile.

hopefully someone here is going to do an oil change soon and can peek behind there with a small mirror!
I have been driving with the one missing connection the last few days... Slowly mostly around corners.

I'll try to use a mirror today. Really want to get this stupid thing resolved before another connection is stressed and snaps off :/
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      05-27-2014, 10:16 AM   #12
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I was under the car a couple weeks ago doing water pump/tstat/E93 M3 FSB install. I reached my hand up into that area and was able to feel the top of the stud. Reason why I was poking around there to begin with was to figure out how to get this thing fixed if I ever ended up in the same situation you are in now lol

The stud you broke appears to be the hard to reach one :/ The difficult part now is finding the right tools to get that stud out of there. Once that is complete, you'll have to put a nut at the top (where the stud head is now) and thread a new bolt in from the bottom (which has to be a pretty exact length to keep from bottoming out).

I had to do the same thing for a stud I broke on an exhaust hanger on my bro's G35. Replaced the stud the same exact way as described above with a much thicker stainless steel nut/bolt combo. Call that "unfinished" if you like, but those replacement pieces are way beefier than the stock pieces they replaced.
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      05-27-2014, 10:41 AM   #13
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Had the same problem last year.
I drilled the pressed-in bolt out and inserted a blind rivet bolt like this...

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      05-27-2014, 11:20 AM   #14
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Quote:
Originally Posted by dbjb View Post
When reinstalling my sway bar, I used my newly purchased torque wrench. Now either this thing is defective or its poorly built. I now know I should have tested it first. Long story short, I couldn't hear or feel a click and I over-torqued a nut on my front sway bar.
Just a side note, is it a possibility that the torque spec was given in lbs/inches and you set it as lbs/foot on the wrench? That would give 12 times more torque than the spec.

Reason I am asking I made that mistake once, when I was more novice with the tools and the torque specs and how they feel on tightness.

Or it was given Newton/meters and your torque wrench is only lbs/foot?
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      05-27-2014, 12:47 PM   #15
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Quote:
Originally Posted by approximate View Post
Had the same problem last year.
I drilled the pressed-in bolt out and inserted a blind rivet bolt like this...

Neat! That's a pretty cool invention...learn something new everyday
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      05-27-2014, 02:39 PM   #16
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Quote:
Originally Posted by FCobra94 View Post
I was under the car a couple weeks ago doing water pump/tstat/E93 M3 FSB install. I reached my hand up into that area and was able to feel the top of the stud. Reason why I was poking around there to begin with was to figure out how to get this thing fixed if I ever ended up in the same situation you are in now lol

The stud you broke appears to be the hard to reach one :/ The difficult part now is finding the right tools to get that stud out of there. Once that is complete, you'll have to put a nut at the top (where the stud head is now) and thread a new bolt in from the bottom (which has to be a pretty exact length to keep from bottoming out).

I had to do the same thing for a stud I broke on an exhaust hanger on my bro's G35. Replaced the stud the same exact way as described above with a much thicker stainless steel nut/bolt combo. Call that "unfinished" if you like, but those replacement pieces are way beefier than the stock pieces they replaced.
I'm going to get under the car again. I'll take another look. I hope I can reach the top but my memory tells me otherwise.

Quote:
Originally Posted by approximate View Post
Had the same problem last year.
I drilled the pressed-in bolt out and inserted a blind rivet bolt like this...

That may be my solution? Can you tell me where you picked up that part? Hopefully somewhere in the US!
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      05-27-2014, 02:41 PM   #17
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Quote:
Originally Posted by PhaseP View Post
Just a side note, is it a possibility that the torque spec was given in lbs/inches and you set it as lbs/foot on the wrench? That would give 12 times more torque than the spec.

Reason I am asking I made that mistake once, when I was more novice with the tools and the torque specs and how they feel on tightness.

Or it was given Newton/meters and your torque wrench is only lbs/foot?
Good question but no... I used it right. I tried it afterward on my wheels at 88 ft/lb. It's just not a good product. Very little indication that the threshold had been reached. I plan on returning it.
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      05-27-2014, 03:42 PM   #18
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Took some more images. I now need to source this "blind rivet bolt" or find a local welder. Opinions and recommendations welcome!

Here's a breakdown...

1) Overall image. As you can see, the bar has begun to pull away from the subframe. Meaning, I need to get this fixed ASAP.

2) Top of rear stud. The rear stud is accessible from the top.

3) Severed front stud.

4) The subframe is about 5mm thick but I can't get my finger on the top portion (blue) because of the subframe's form (red).

5) Mirror showing severed stud thread and top.
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      05-27-2014, 04:04 PM   #19
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Quote:
Originally Posted by dbjb View Post
That may be my solution? Can you tell me where you picked up that part? Hopefully somewhere in the US!
the only cheap solution!
or u replace the whole front axle support...

u should get these bolts (m8 thread) in every good hardware store for a few cents.

for the installation, u need special tool. but a metalworking garage should have one of these.

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      05-27-2014, 04:04 PM   #20
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1. Just remove the FSB altogether until you can get this issue sorted.
2. How much space is between the top of the broken stud (blue) and the next section of subframe (red)? Is it enough to fit a decent sized nut in there?
3. How do you expect to replace that stud even after acquiring a welder? There is no way you're getting a new stud through the top of there. That red part of the subframe was welded to the rest of the subframe AFTER your broken stud was set into place at the factory. Not sure what your logic is behind this...
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      05-27-2014, 04:07 PM   #21
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Quote:
Originally Posted by approximate View Post
the only cheap solution!
or u replace the whole front axle support...

u should get these bolts (m8 thread) in every good hardware store for a few cents.

for the installation, u need special tool. but a metalworking garage should have one of these.

Even with that special tool, you still need a lot of room/access to the top of the stud itself. The top piece of the subframe for this stud location makes this an impossible solution IMO.
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      05-27-2014, 04:26 PM   #22
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Quote:
Originally Posted by FCobra94 View Post
1. Just remove the FSB altogether until you can get this issue sorted.
2. How much space is between the top of the broken stud (blue) and the next section of subframe (red)? Is it enough to fit a decent sized nut in there?
3. How do you expect to replace that stud even after acquiring a welder? There is no way you're getting a new stud through the top of there. That red part of the subframe was welded to the rest of the subframe AFTER your broken stud was set into place at the factory. Not sure what your logic is behind this...
1) Good idea. Might just do that. Have to remove the support arms too. Sigh.
2) Can't even get my finger in there. If a nut could fit, it would be difficult to align and impossible to torque.
3) Good question. My thought was to get a long bolt and hold it upside down (thread facing up) into the bored out orifice. . Weld into place then cut off the bottom hex section. That would form a stud. Just brainstorming. Unsure if that would work well.
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