Replacing bolt(s) on door.

[JohnMcPhee]

Hello,
I have a bit of an issue with my driver side door in my roadster.
It has been sagging and not closing or opening very easy last summer, so I decided to adjust it.
The previous owner/builder cross threaded two out of the four acorn nuts on the door. Two loosened up and two did not.
I was able to use WD-40 and PB Blast and get one of the nuts off, but it took most of the threads off when it came off.
The last bolt came unattached from inside the door when was trying to loosen and tighten to free up. I ended up using an air grinder to remove the nut.

Pictures included to show this mess.

My question, has anyone replaced one of these bolts? If so, I’d like to inquire what you used, I’m thinking of using a marine-tex epoxy.
I figure to fill the hole with the epoxy and then coat the head of the bolt and insert, and then place the door in the hinge to insure properly alignment and let cure for a day or two.
Any better suggestions sure be appreciated. I want to inquire with those with more experience in this sort of fix then myself, before I attempt this repair.

Thank you.

8349583496

[michael everson]

To the best of my Knowledge these were always welded to the door frame. Unless you can get inside the door and weld in new bolts, you might be stuck. I would try drilling out what's is left and thread a hole. Then use bolts to hold the door on.
Mike

[edwardb]

No way I'd trust any kind of adhesive to hold a bolt for that application. As Mike said, those are bolts welded into the door frame before it's molded around. I can think of two solutions: (1) Install heavy duty nutserts at new locations. Something like these: https://www.mcmaster.com/#95105a159/=1c9bsiw. I've used the 1/4 and 5/16 inch sizes of these parts. They're quite robust. The 3/8 inch size in the link is the same size as the door bolts. (2) Cut a big enough hole in the center of the door that you can reach inside and hold the back of a bolt to replace the damaged ones. If you don't have door cards already, this would be an excuse to get some and would cover the hole. This is probably what I would do FWIW.

[CraigS]

I agree i don't think an epoxy is going to hold well enough. Is the bolt that you cut the nut off of still there or did it drop into the interior of the door? If it's still there could you help it fall into the door to get it out of the way? If you can, I would get a 7/16 or 1/2 in fine thread tap and thread the hole so you can install a bolt vs a stud and nut. I also like the nutsert idea but buying a tool for one nutsert makes it an expensive repair. If you decide to cut an access hole you could epoxy in one of these even though they only go to 5/16 inch
https://www.mcmaster.com/#studs/=1c9ju6h

[JohnMcPhee]

Wow great information. I thank you all very much!
I will look into each of your suggestions.

I guess it was wishful thinking on my part.

[GFX2043mtu]

I completely agree with Edward. If it where me I would drill out the bolts and use a hole saw in the door to get access and cover the hole up with some nice door cards. Just be careful where you put the hole as FFR uses a lattice structure in the doors. Make sure the hole you drill clears it for access reasons