merkis1024

I've been asking a lot of questions in this section this week, since I was doing my first clutch job and I really appreciate the support and help this community has given this new S2000 owner. I found a few topics that dealt with stuck or broken subframe bolts, but I couldn't find my specific issue.

The previous mechanic torque the living daylights out of the subframe bolts and I ended up buying a 300 lbf ft impact wrench to do all 6 bolts..
I had no issues with the rear 17 mm's and the center 19 mm's. But the front 2... as with everyone else ... is giving me a headache.

Luckily, mine didn't snap yet. knock on wood..
But, it won't tighten all the way in. I thought of just replacing the bolt with a brand new one, so I was going to take it out just to see how long it is. It won't come out either.

So, right now, the bolt is almost all the way in, leaving about an inch of gap from the bolt head to the subframe. no matter what I do, it just spins freely and does not bite the threads when I try to tighten them. If I try to remove the bolts, it still does the same thing. Doesn't grab anything and just spins freely... I tried pushing the bolt down with a wrench while unbolting to see if I can get it to grab, but no luck..

What do I do in this case? Do I just drive it with the front bolts not installed all the way?

AE_Racer

Sounds like you cross threaded the bolt and the force broke the welds holding the nut inside the body. You can replace these but from what I read before it entails cutting out part of the body/frame to gain access to the nut. I stripped two of mine, one on each side, I think the fronts(long story). I didn't have the tools or time to go through above process so those two bolts never went back in. I'm sure it would be advised against but i've put 100,000 miles on my car since including auto x and a track day without issue. Nothing weird with my alignment either.

Car Analogy

Not following. These 2 bolts were in all the way before you started, yes or no?

You loosened these 2 bolts from all the way in/tight, and removed them completely, or just loosened them to how far out they are now?

You say they won't tighten, but then you also say you can't remove them even if pulling down? Which are you trying to do, loosen them or tighten?

My guess is the bolts just aren't lining up with the the threads they need to engage. Try loosening the other bolts, and shifting the subframe around as you try to get them to thread. Make sure not to crossthread them. If they aren't threading in easy, back out and try again.

One trick I use is to turn a bolt backwards while applying a little pressure, and you will feel when the thread of the bolt falls off the ramp of the thread of the nut (bolt drops in a little). This means the threads are now aligned and if you tighten the bolt from this point threads will engage cleanly.

If you want to remove the bolt to inspect, grab the bolt head strongly with a pair of vise-grips, and pull down while doing a loosen-tighten motion back and forth with the vise-grips. Put some elbow grease on that and bolt should come out.

merkis1024

god, I really hope that the welded nut did not break off.. I want to believe that the subframe will hold without that nut, but I'd feel much more comfortable with all the bolts installed correctly.



So, when I first went under the car, the front 2 bolts were tight. It took hell of force to unbolt, and I just took a lunch break and picked up an impact while out. It unbolted a little more easily, although the impact was constantly hammering as it unbolted. I don't want to believe it, but it may have stripped some of the threads during this process.. I did not remove it completely. I lowered it to about 3 inches. When I tried to put it back, it bolts in about 1.5~2 inches, but it suddenly just became loose and was spinning freely. Thinking I may have a damaged bolt, I was going to just take the bolt out and replace, but no luck. When I try to turn it counterclockwise, it just spins freely again.

I will try using the vice grip to pull down while doing the loosen-tighten motion and seriously pray that it's just a bolt, not the nut in the frame..

james0933

Good luck.

AE_Racer

In that case you may have just damaged some of the threads on the bolt so now it won't catch and thread in/out. Which would be better than the worst case I mentioned. Good luck buddy.

Ryuu

if your talking about the 6 front sub-frame bolts.. according to Honda, they are to be replaced.. if you can get them back out.. pg 466 of the service manual.. special bolts all 6... replace... good luck...

Billman250

You have quite a mess.

You will need to get a large forked prybar on the bolt and apply downward pressure, then try to impact it out. If the nut is not broken free, the threads may catch and the bolt might start to come out.

If the welded-nut inside the frame broke off, all bets are off. You will need to cut open an access hole in the frame to access that nut and cut it out. Weld in a new nut-sert.

This is by no means an easy job, done a few already.

merkis1024

Thank you Billman. I tried the prying while impacting method. I didn't have a forked prybar, so I just used a plier tool to essentially do the same thing.

I got both the bolts off. One of them was completely destroyed. No thread left whatsoever. The other was fine. Hopefully, with a brand new bolt, it will install nice and flush

Thanks again!!

freq

this place is amazing.