240z bumper brackets broken bolts.

[2sixTZombii]

Hi, I bought a 240z style bumper for my early 260z, After I got it repainted only did I realize that the 240 brackets didn't line at all. Well I decided to pull the brackets off to figure out a solution, So I went at it and regardless of how WD40 I used or how much I qire wheeled the threads the bolt made it half way and promptly broke. I still have one on one side but on the other they are both fubar. The smaller angled brackets appear to be welded to the bumper itself, and I can't reweld them. I need to remove the old bolts, but see no way to replace them, I have a few ideas but am really lost on how to get them out other than drill them out. Are they welded in place or could I drive them out? I feel like this had to have happened to someone once before. It would appear that once reversed the 240 brackets are close to lined up the right width and with some bending I think that will work, but is the depth anything close to right as far as where the bolt hole will line up? I'm not as concerned with mounting I am with the broken bolt issue.

[Mikes Z car]

I won't be able to help though this picture of a bracket on a 240Z re ar bumper may be a reference for someone else. I had a struggle replacing the nuts and bolts on this bumper.

[ajmcforester]

If I remember correctly the stud is tack welded to a strap of sheet metal welded to bumper. With a small grinding tool grind the stud welds and weld on a new stud or just thread a new bolt with a lock and regular washer so it don't move.

[2sixTZombii]

But I can't get get back there with a grinder because the whole strap is welded in place, and I don't a welder to redo if I break the welds.

[Mikes Z car]

Drilling out the bolts would be a lot of work but if that were done it might be possible to do a repair as shown in the drawing if a new bolt is chosen so as to be long enough to compensate for the thickness of the scrap metal used for repair. Maybe someone else could weigh in with their ideas. If the bolt doesn't want to come out when drilling keep making the hole bigger until it does. The straps those broken bolts go through could possibly be bent upwards somewhat for easier access to the back side or even the end cut off and welded back on with a new bolt. I have used a dremel on my car and have had good results in tight places for cutting/grinding though I did have to replace the drive belt once. Some of them might be direct drive. I have used an ordinary drill with a grinding stone also with some results. FWIW.

Edited November 27, 2013 by Mikes Z car
grammar, better ideas etc

[2sixTZombii]

One Idea I had was to cut (with dremel) a square shaped channel around the bolt, and drill a large hole leading to it so once the old bolt was gone I could just stick a carrigage bolt with the square shape around the base in the large hole and slide it over with the channel. Sounds a lot of work for a simple problem though. Wish I had a welder.