My youngest son came home today and said my car is making a rattling noise in the back.

The pics show what I found. Seems like the top bolt holding the rear Hotchkis sway bar backed out of the hole (I guess I didn't use enough thread-lock when I put it in).

Seems like a simple fix, but the bolt must have rattled around in the hole before it fell out, because the hole is too large and the threads are stripped as I cannot get a new bolt to stay in (I still have the stock hardware).

Can I tap the hole and re-thread it for a slightly larger diameter bolt? Any other repair ideas. The car is a 2003 Honda Civic Si hatchback, daily driver for my high-school son, and just has to last us another 15 months or so until he heads off to college.

 

Looks to me like that should be a shoulder nut on the other side...

You could use a Steel Thread Insert if no nuts are used. (see image) this insert would require you to match it to the bolt used, then with the insertion tool install the insert (it uses a compression tool, to compress the insert) (see tool image)

My question would be, what event exerted the force to the sway bay mount to pull the bolt out?

Motor on!

 

Thanks for the info. My assumption was that the bolt just worked its way loose over time. That bar has been on the car since 2005.

If I follow you, you say that there SHOULD be a nut on the inside of the subframe that the bolt threads into? I can try to inspect one of the other bolt holes and see. Your solution sounds like it would work. Where would I find a tool/insert like that? Body shop? Independent garage? Honda dealer? Machine shop?

I don't mind spending some money to get it fixed, but the car is almost 13 years old, so I'm not going to drop a ton of money on it...

 

You can't get to the backside of that hole? Easiest thing to do would to just thru-bolt it with a nut and bolt. There probably used to be a captive nut inside the subframe that the bolt threads into. Maybe the welds snapped and the captive nut came loose. If that's the case you're in a bit of a pickle. You can try to tap it for a larger bolts size but you're likely just tapping into fairly thin metal which won't hold.

I'm not sure I'd trust a nut-sert to hold up to the forces exerted by a swaybar but I guess it's easier to try than some of the other options.

Why not just remove the swaybar and run with no rear swaybar? Won't be as much fun to drive but it isn't going to hurt anything. The swaybar isn't a suspension locating component in the rear of a honda.

 

You could drill it out and tap to a larger size bolt, say from 10mm to 12mm or what ever size the current bolt is. Either way you do, shouldn't be to difficult or time consuming. How much meat/metal is in the mounting area that might determine what you can do.

Tom

 

The metal looks plenty thick enough for a nut-sert. I do believe you can borrow the tool at NAPA to install them. If not, ask around some parts shops and see if there's a loan a tool program. It's a rather expensive tool to buy just to put one insert in.

 

Not sure if I can get behind it, as I just did a relatively quick assessment on Sunday. I was busy trying to diagnose a coolant leak on my MINI. I believe that the bolt inserts into the "frame" of the car, and it is completely boxed, but I could be wrong. I'll take a more thorough look this weekend.

 

That was my first thought, as long as the steel there is thick enough. I'll take a better look this weekend.

 

Yeah, I don't want to buy the tool... just use a loaner. I'll have to see what my options are when I can take a look this weekend.

Thanks ALL for the feedback. I'll post what I find out.

 

Alright, took me longer than expected to do a more thorough inspection, but here is what i found.

From the looks of things, there was a captive nut in the upper location as it cearly existson the LOWER bolt location. The frame rail is completely boxed, and I don't see any way to get in there to place another nut.

That leaves me with the option of attempting a nut-sert or trying to tap the existing steel for a larger bolt. From what I see, the nut-sert looks like the better path, as the layers of steel do not seem thick enough to really to any type of threading that would hold.

My third option would be to fab a bracket and weld it in place at the top, bolt it at the bottom. I'm going to visit my old Miata mechanic, who also runs a race shop, and see what he recommends.

More to come...

 

You could weld a stud on there & use a nut to hold the swaybar mount on.

 

Shop basically did the reverse of that. They drilled out the hole to be able to put a nut in it... Welded the nut to a plate, inserted the nut in the hole, and welded the plate to the car frame that they ground smooth.

It works, it's sturdy, and it cost me only $107. I'm happy, and it will get my son through his last year of school before I replace the care completely.

 

Glad it worked out!

 

I have a case of dyslexia, so what I'm saying is I meant exactly what your shop did. Glad it worked out for you.