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Well, I've gone and complicated my life further somehow. I had the crossmember bolt (which holds up the rack and pinion on my car) loosened but still in the hole, and was using it to help maneuver the rack back into place. Somehow this has caused it to royally booger up the threads. When I went to tighten the bolt back up, it was hard to turn and eventually ended up crossthreaded. I went ahead and pulled the bolt back out and shot some WD40 in there and got some nice metal flakes back in return.

So question 1: is there a good way of fixing this? Obviously, I don't want to ruin the threads entirely as I don't have the resources to put a new nut into the frame rail. Would a tap work? If so, what thread size/count do i need?

Question 2: would it just be better to crank it on up there and let the bolt cut its own threads? I'm not sure how robust the threads are in this thing so not sure if this would totally ruin it or if it would be okay. Somethings are more or less fine when crossthreaded, other things end up stripped. See above concern - do not have the resources to weld in a new nut, so this one's gotta get fixed.

Thanks for any and all advice. Still not sure how I accomplished this one but it is getting a bit ridiculous by this point. This suspension rebuild should have taken a weekend and instead has stretched to two weeks of mishaps and retardation... kind of a lot of stupid issues, even for me.
 

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So question 1: is there a good way of fixing this? Obviously, I don't want to ruin the threads entirely as I don't have the resources to put a new nut into the frame rail. Would a tap work? If so, what thread size/count do i need?

Question 2: would it just be better to crank it on up there and let the bolt cut its own threads? I'm not sure how robust the threads are in this thing so not sure if this would totally ruin it or if it would be okay. Somethings are more or less fine when crossthreaded, other things end up stripped. See above concern - do not have the resources to weld in a new nut, so this one's gotta get fixed.
I would gently try re-tapping. I would not try force.

According to the AMK catalog the bolt is 1/2-13 thread (379068-S).

Good luck
Paul
 

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I assume it's these bolts that got boogered:
https://www.npdlink.com/store/products/mounting_kit_front_crossmember_concours_correct-149348-1.html
If so they're 1/2"-13 thread which is a standard 1/2" coarse thread.
Go to Harbor Freight in Austin on Parmer Lane (north) or South Lamar (south) and buy one of these tap & die sets:
40 Piece SAE Carbon Steel Tap and Die Set
This set is just Carbon steel instead of High Speed steel and they're not very sharp so they function quite well as "thread restorers" instead of "thread cutters". You can buy the whole set for the same price that you'll pay for 1 tap and 1 die at the hardware store.
 

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Discussion Starter #5
Hmm, interesting idea on using not-very-sharp taps to restore threads instead of cutting them! Does that actually really work? o_O

Thanks to all for the suggestions - tapping it does seem like the best option. This car is going to give me ulcers someday, I just know it.
 

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Thanks very much! Will report back tomorrow with results. I'll either be totally infuriated and utterly defeated (and in need of someone who can weld on my car in my garage), or I'll be elated. Let's hope Jane gives me a break and I get to feel the latter.
 

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Discussion Starter #11
What's the difference between a thread tap and a "thread restorer" like that? Looks the same to me, except the thread restorer doesn't have the pointed tip for starting new threads?
 

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What's the difference between a thread tap and a "thread restorer" like that? Looks the same to me, except the thread restorer doesn't have the pointed tip for starting new threads?
It's not sharp like a tap that cuts threads. A thread restorer will straighten the threads where as a tap will just cut them. It'll leave the most of what you have.

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How is that different from just running a bolt up the threads then? My concern is pulling them out since it's already cross-threaded. Not sure how it would straighten the threads any differently than a bolt would...?

The bolt that goes in this hole has to be torqued to 80 ft/lbs, in case that matters.
 

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The bolt has no way of straightening the threads. As you mentioned the chasers look similar to taps. They have flutes just like taps but the edges of those flutes aren't cutting surfaces like a tap, they're designed to straighten the damaged threads. If you use a tap you will remove more threads and imo that's not acceptable in this situation.

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You want a thread chaser tap, not a thread cutter tap, new or worn. Craftsman makes them, as well as other manufactures of tool and die equiptmemt. Even the chaser taps are going to remove some of the mashed up metal in there. Saying it removes no metal is wishful thinking. But it's way better than a plain tap.

The captive nut you are trying to fix is not exceptionally deep. It is already seriously compromised by the sound of your description. Is your whole R&P held on by just these two bolts ? Safety wise, Not something you want to count on when half of the threads are missing.

If you are still in Austin, I'd be calling on Micheal B. of Cedar Valley Motors, a Mustang and Shelby wizard, his advice and help are your best bet to extricate yourself from this mess.

PS ( Tell him I said Hi. )

Z
 

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Different location, but I recently had a similar problem on one of the captive nuts in the front frame rail for the front number brackets. The front bolt was actually broke off flush with the frame rail. What I had to do is drill a small pilot hole in the remains of the bolt. About half way in, guess what...the damn twist drill broke off in the bolt. Awesome. Next step, I had just ordered and received a set of high speed dual cut burrs from Eastwood. Started with the small one grinding through the twist drill and the bolt and work my way up to the round burr which allowed me to then run a much larger drill through the remainder of the bolt. Finally got all of the old bolt out. The point of saying all of that, was I eventually had to run a tap into the nut to clean it up. I will agree the thread chaser taps are probably a better option for this as I believe they actually just reform the threads instead of cutting new. However, like you probably I only had a full set of regular tap and dies. So I pulled out the right tap and machine oil and went to town. End of the day, it worked perfect. Installed my new bumper bracket bolts and it tightened up just like the other three with no problem.
 

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I've run into this as well. I agree that the thread chasers are a better idea than the tap, so if you have the option, go with the thread chaser. All I had at the time was a thread tap, and it worked fine. I've had the crossmember off and on several times since I re-tapped the nuts in the frame, and it's been fine every time.

The only possible issue I can see is if there's not enough material to work with (which, if you're seeing metal flakes, might be an issue), then tapping it instead of chasing it might cut too much and destroy what's left of the threads. If it was a different location you could probably get away with using a bigger bolt, but that won't work in this case. The heads on the crossmember bolts are designed to pull the crossmember into place as it is tightened.
 

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Best and strongest option without replacing the capture nut would be to install a helicoil. You will need a 1\2-13 helicoil set which will include a drill bit to drill out the old threads, a tap to cut new threads for the helicoil, an installation tool to install the helicoil, and the helicoil itself. End result will be as good or better than new.

Rick
 

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What concerns me in the OP's case is that she isn't just hanging a crossmember off of a re-tapped nut. She's got an R&P unit which weights considerably more, and is liable to be a genuine buzz-kill if it ever comes loose while she is driving down the highway.


Z
 

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What concerns me in the OP's case is that she isn't just hanging a crossmember off of a re-tapped nut. She's got an R&P unit which weights considerably more, and is liable to be a genuine buzz-kill if it ever comes loose while she is driving down the highway.


Z
Excellent observation here. Not only that, but the original torque spec for those uniquely beveled and critical bolts was what? 45-60? Kelly says she needs to be at 80 for the R&P. Those threads need to hold, and good. A "genuine buzz-kill" indeed if the threads fail, and that would most likely occur under strain while driving.
 
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