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A while back I replaced the driver's side door check strap. In doing so, I stripped the top bolt that bolts to the chassis, and half of it broke off in the hole. I was able to tighten the bottom bolt enough to where the check strap was usable, with the intent of eventually removing the broken bolt. Well I attempted that this evening and completely botched it. Not only could I not get the broken bolt out, while hammering the extractor in I bent the bracket that the bolts screw into behind the chassis. I managed to carefully get the bottom bolt back in so I wouldn't have to take apart the door again to remove the check strap, but it's not as tight as before and will definitely need attending to after awhile. (Would also bet that bolt is stripped now, too)
How do I access where that check strap bracket is behind the chassis? Will the fender need removing, or maybe just the door? Any suggesting are appreciated.
A thought I had was to twist that bracket back so the top hole is visible again, and JB weld a stud in the threaded hole with threads sticking up through the check strap. Secure the strap with a nut on the stud.
A thought I had was to twist that bracket back so the top hole is visible again, and JB weld a stud in the threaded hole with threads sticking up through the check strap. Secure the strap with a nut on the stud.
if the hole is visible, does it just need to be re tapped? Drill and retap not an option?
If I were in your shoes I'd pull it back off and fix the threads properly. Looking at the picture, the witness marks on the lower portion of the bracket don't look aligned how it was originally installed.If I were a betting man, I'd say you tightened the bottom one to keep it in place, then tried to install the top one. The right way to do this is hand start both bolts and then attempt to tighten them in the same vertical positions that they were found in.
It sounds like you cross-threaded the bolt or overtightened it until it broke. I'd center punch the broken bolt, use a small pilot bit to start drilling the bolt out and gradually increase bit size to prevent breaking a bit. Use cutting oil, quality bits and take your time. High bit speed will burn up/dull bits when drilling metal, particularly stainless. If it's cross-threaded I wouldn't bother with an extractor or even a reverse drill bit because there's good chance that you'll break them off in the bolt. If the threads are trashed, you'll have to re-tap as Baltistyle said ^^^, possibly even go with an oversized bolt if they can't be restored to the original thread size. If it WAS NOT cross-threaded, in most cases you can use a reverse drill bit and it will eventually spin the broken remnants out.
Sorry for the long reply, but I'm no stranger to fixing broken bolts and hope my advice helps you out. If your bracket is bent to hell you need to address that first.
I bit the bullet and drilled/tapped a new hole to the left of the old one. I have NO idea how, and I wish I took a pic first, but the broken bolt was sticking OUT of the original threaded hole, where as before I reinstalled the bottom bolt as a temporary measure it was fully inside the hole. The bracket shifted to the right when I installed just the bottom bolt and tightened it, it most likely turned the bracket. But I've truly no idea how it went from being broken off inside the threads, to sticking out. When I tried extracting it it wouldn't budge.
Anyways, pics below. Yes the threads are extremely shallow. But, the purpose of the top bolt at this point is to keep the check strap bracket from pivoting when opening/closing the door. The force is lateral against the bolts, so I think those threads are sufficient. I think the "proper" fix for this is to take an angle grinder and cut out a rectangular hole and weld in a new bracket.
Appreciate the replies. Feel free to discuss further. This is going to be a problem for anyone that has to remove the check strap or is just replacing it. The bolt stripped as I was removing it for the first time, so not really anything I could of done to prevent it.
This car is now my only car, so I really needed to get that top portion secured so it didn't do any damage. It was either that or remove the check strap completely, which feels like quite the risk. I forget one time and the door goes flying into the car parked next to me, lol.
Last edited by sushistrip; Jul 20, 2024 at 08:13 PM.
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