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Sheared Bolt - Sway Bar Bush Strap to Chassis

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pkmh

pkmh

Jedi Warrior
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Never realized just how bad all the pieces were to my sway bar assembly. Even after using generous amounts of PB Blaster and working the fasteners slowly, etc., one of the bolts I attempted to remove from the bush strap to the chassis simply sheared off.

I believe one way to remove the sheared portion is to first drill a small hole in the center of the sheared portion and then use a type of tap to either screw the threaded remains all the way into the chassis or reverse it by continuing to unscrew it out.

I've never had this problem (just lucky I guess), and if there is a better way or other details I should know, then I would much appreciate any advice offered.

Thanks for whatever can be offered!

Paul
BJ8
 
I've been there many times. In my opinion it would be best to heat the broken bolt red hot and let it cool off if you want to try and extract it intact at this point. If you do not break the rust bond you risk breaking off a hardened tap or extractor , which now turned a bad situation to crap. Its a 5/16 " NF thread so start with a new 1/8" cobalt drill bit and drill it exactly on center all the way through. I'd go up a few more sizes to 1/4" at that point and extractor driven in well should loosen it up enough to pull.
 
Use a center punch first to locate the drill point properly. Take your time, be careful to not break off the initial drill bit in the hole. :cheers:
 
I had the other problem. The weld nut broke loose inside the frame rail. I now have only one bolt tight and the other is just nearly tight, but it still holds the sway bar in place.
 
I believe the inestimable Randy "Swamp dweller" Forbes milled and tapped a thick piece of steel with which he replaced the end of the frame where these problems appear. Both Randy and Andrea the Italian kindly shared their methods/pictures which are to be found in the search archive.
 
Swamp dweller, lol! Hoping to move into the new digs in 4-5 wks (fingers crossed).

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More pictures: https://www.spcarsplus.com/gallery3/index.php/reMKIII/work_from_3-25-11_onwards?page=2
 
Then we'll hold of on the name for awhile. :laugh: Looks like it's moving along well, you will have to get a street to go with the nice street light.
 
Actually, it's on one of the (very) few "named" street in Manatee County; Mulholland Road (unfortunately, it's not <span style="font-style: italic">Mulholland Drive</span>, but still livable). When a development plan is submitted, Manatee County requires that all the streets be designated, so a lot of the developers (lacking imagination, it seems) give most of the streets as numbered streets, avenues & roads.

Fairly confusing too, as there's no guarantee any street group is numbered consecutively either.
 
Thanks for all the advice. I will come back and post my results and procedure.

In attempts to find or mark the center of the sheared bolt before drilling using a cobalt bit, I plan to use a dremel using a type of carbon bit or diamond bit (they appear silver in color and having the texture of fine sandpaper). That'll make drilling into the center of the sheared bolt a bit easier.

Again, thanks.

Paul
 
I appreciate Randy's pics of repairing the sway bar mounts, but I have no welding equipment or experience. I'm OK for now, but someday I'd like to learn something about welding.
 
Nevertheless, start the process with a center punch. If you have to use a file or such to flatten the sheared bolt so you can find the center that is fine, but it is wise to start the process with a center punch so as not to skate around with the drill. This is a TRIED and TRUE method. Even the diamond drill bit can skate easily. There is a reason that the center punch is still being used. Because it works and can be placed accurately with ease. You do not have to reinvent the wheel to achieve your aim. :cheers: :
 
A couple of points. If you get your center punch mark slightly off the mark, angle the punch and do it again. You can move the mark to exactly where it needs to be. Secondly, DO NOT buy the Harbour Freight reverse drill bits. There is a reason the entire set sells for only $9.99. The good news is that if you break off one of those cheap drill bits, you should be able to drill it right out because it has such a low carbon content. That's why it broke - it's soft. Put your $10.00 toward a good quality tool that's made in America.
 
 
Guys

In my experience of drilling out rusted in bolts or studs, you can never get the centre punch spot on. Further more you can never get the drill at a perfect right angle to the work piece. My solution was to drill a small pilot hole first, then gradually step up the drill bit sizes stopping short of the bolt or stud size. At this point it should be easy to drive a sharp thin point down between the weakened bolt and the nut or threaded plate to collapse the wall of the drilled out bolt or stud and then get it out with long nose pliers.

Cheers

Bob
 
In addition, sometimes one runs across a sheared large bolt that resists all efforts to remove it. After drilling the center out as large as you dare, insert a hacksaw blade and make a cut down the length of the bolt until the threads appear. If this does not relieve the bolt make another cut a small distance away. This weakens the ring that is left of the bolt and greatly assists in it's removal. Just be careful to not disturb the threads that line the hole. [Unless, of course, you must.]
 
I've found that with a variable speed battery powered drill I can steer a wayward drill towards the centre of the hole. It's surprising how far you can tilt it to get it central.

Years of drilling snapped off 1/4" BSF exhaust manifold studs in post war six cylinder Bentleys and R-Rs!
 
I like the post above about creating a pilot hole first instead of a punch mark. That is what I was trying to explain earlier by using a dremel and a diamond bit (a bit that is in the shape of a small ball or other similar shape bit), thus making the creation of a pilot hole much easier than a punch mark. The pilot hole I will "sculpt" will be left in the form of an inverted cup, making it easy to just place a bit in it and start drilling.

Moving along, today, I bought a couple of cobalt drill bits. All by Ridgid (Made in China, as I now see) A 1/8", 3/16" and if need be, a 7/32". Then I bought two sets of different "easy out" extractor sets. Ryobi (again, China) and Grabit Pro (Made in USA). I am incline to try the Grabit brand first because it allows you, by reversing the bit, to reverse direction or go clockwise as well as counterclockwise. The set is good up to 5/16" [sheared] bolts.

However, Ryobi's extractor set has more spiral, conical configuration to their bits or giving the apprearance it will grab more within the [sheared] bolt, after drilling has been done.

I also had been advised to apply heat to the area around the sheared bolt and then apply ice to the actual sheared portion.

I will keep the hack saw idea in mind, too, but I hope my efforts don't have to go that far.

Any additional thoughts??

I will proceed with this problem soon enough.

Thanks,

Paul
 
Hey all,

Finally worked away on removing my sheared bush strap bolt today.

All things considered, 'surgery' went well. I will post a few photos within the next few days, especially after my new sway bar assembly is installed.

The tasks that went well was the creation of my pilot hole using the dremel, and then drilling in succession the various size cobalt bits. The pilot hole created was centered right on the money and drilling also remained concentric along both the X and Y axis as I went (which meant shifting eye focus from foward to sideways as I was drilling away).

But attempting to remove the sheared remains with the easy out taps, along with applying heat and ice and even cutting into one, then two sides of the screw thread wall opening proved to be not enough to rid the remains. It is as if the sheared remains became bonded to the chassis. I also didn't want to overdo twisting the taps, risking shearing in the opening which would of really put me in a bad mood.

The only sensible option at this point was to create the next larger diameter opening and tap new threads. I decided to use 10mm and because I found it to be just the right larger size as well as the screw threads being finer and more per inch than the SAE equivalent available at that moment. Sorry I cannot give more details than that but I am pleased in every way the results. I realize one other slight modification will be to increase the opening of one hole to one bush strap. But this is ever so slight.

Photos to follow and thanks for all the advice!

Paul
 
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