[blbrchnk]

So as the title says, I put on a new set of vrsf down pipes this weekend. All was well enough (this is a painful process on the xi) but in order to get them in you have to drop the subframe. When I put it all back together, everything was semi-lined up and when I got to the last sub-frame bolt, I started tightening and it got really tight. Of course you know the ending, I am about 1/4" away from getting it all the way in and just cannot get it to budge.

I tried forward/backward, heated with a torch, impact wrench (not a very strong one nor a strong compressor), torque wrench, all to relatively no avail. So my question is, does anyone have any other suggestions? The subframe is rather snug enough with the 5/6 bolts but obviously I don't want to leave it like that.

[Riick]

Take bolt out, find thread pitch, buy a tap that fits said thread pitch and clean up the threads on the car. Possibly buy a new bolt. Hopefully they're not too gummed up enough to require drilling the hole and installing a heli-coil or other method of thread replacement. If it only needed 5 out of 6, bmw would have used 5 not 6. It needs to be there.

Never, ever install bolts with anything but your fingers. If it doesn't screw in or very hard to turn or stops, find out why and resolve the problem. Do not EVER use mechanical means (air gun, etc) to install a bolt. Always finger start it at least 3 threads deep before going with tools.

[blbrchnk]

Originally Posted by Riick

Take bolt out, find thread pitch, buy a tap that fits said thread pitch and clean up the threads on the car. Possibly buy a new bolt. Hopefully they're not too gummed up enough to require drilling the hole and installing a heli-coil or other method of thread replacement.

I myself can't get the bolt out, just don't have strong enough tools. I have an appointment to see if a shop can for me, but I was hoping someone had some tricks for me to do it myself.

[Riick]

Originally Posted by blbrchnk

I myself can't get the bolt out, just don't have strong enough tools. I have an appointment to see if a shop can for me, but I was hoping someone had some tricks for me to do it myself.

Heat and a big breaker bar. Possibly pipe on end of breaker bar. Be gentle and hope the bolt doesn't snap. Why on god's green earth would you try to tighten a bolt that won't screw in? It's not going to magically fix itself and continue screwing down like normal.

Do yourself a favor and take your impact gun, pack it nicely in a box, and throw it in the garbage. They are the destroyer of worlds.

[blbrchnk]

Originally Posted by Riick

Heat and a big breaker bar. Possibly pipe on end of breaker bar. Be gentle and hope the bolt doesn't snap. Why on god's green earth would you try to tighten a bolt that won't screw in? It's not going to magically fix itself and continue screwing down like normal.

Do yourself a favor and take your impact gun, pack it nicely in a box, and throw it in the garbage. They are the destroyer of worlds.

By the time I realized what had happened it was too late...

I bought the impact gun yesterday as a means of trying to get it out. It was a last resort on my end.

[Ml3456]

You have to get it out and re-thread the hole like Riick said. Getting it out is the issue now, and you have to think where is it going to break. You could but a breaker bar and pipe on it and see if it will come loose. Can you get a set of channel locks on the shaft and try turning it by both the head and shaft? Get some help. It has a good chance of breaking which will require removing the subframe I'm afraid. Heat wont help to much because you can't get it on just the frame very well to expand it. You will expand both probably and there is no corrosion to worry about since you have it out already. Try to get some penetrating oil in it so once it starts moving it might come out easier.

Good Luck.

[Ml3456]

You also should loosen the other 5 bolts to be sure the frame isn't binding the bolt in any way.

Keep us informed!!