Stripped seat belt mounts

[junkpile]

69 charger, I am doing improvements on. Found the bolts and holes for the front seatbelts on the floor are stripped. Tapped holes are smoothed out, bolts the same way. Guess the previous owner did a little over tightening.

I do not want to use Helicoil just as a safety issue. So I was wondering, since the 7/16 x 20 treaded holes are shot, would it be a good idea to tap them out to take a 1/2" x 20 grade 8 bolt. if that is even possible. I am installing a new 3pt belt system from Morris automotive. My 13 year old daughter loves to ride up front and help me with the car, I want to make sure this is safe for her.

 

[PurpleBeeper]

I personally think your idea is a good one if you're not worried about being "original". I believe the metal in that area is a little thicker, so as long as you stay within that thick metal (maybe even go metric so you don't have to go all the way to 1/2"), then why not? You "could" also use longer bolts & secure them with a nut/lock washer underneath too if you wanted to be "super safe". I agree with the safety....especially for your daughter.

 

[Mopars & Missiles]

There's a nut plate welded onto the underside of the floorboard that the seat belt bolts thread into. You could drill out the spot welds and then weld on replacement nut plates to get it back to original for the bolt holes.

On second thought, I think the bolt holes on the side by the doors (where the retractors go) are into the rocker area, so those would be harder to replace. The center ones though are in the tunnel area and easy to get at to weld in new ones.

 

[junkpile]

I may just try the 1/2 x 20 and cut new threads. the only screwed up ones are the rocker panel holes. I believe I can clean up the tunnel mounts and just use new hardware. I was trying to see if anyone else had this problem and if cutting 1/2 threads would pose and issue with the floor mount. I don't want these pulling out in a wreck that I hope I never have.

 

[oldbee]

Go with “purples” idea & yours. You might have to enlarge belt anchor slightly(?) , easiest way to go.

 

[dart4forte]

Seatbelt bolts have a different pitch than a standard bolt. The bolts are designed to be resistance fit. Tour situation is the result of someone using a impact gun to install the bolts. Never use a rattle gun to install seatbelt bolts. The threads will pull out.

 

[YY1]

I was going to say, I believe they are a special, "self locking" bolt.

I'd at least jamb nut or add a self locking nut under the floor if you do drill them out and re tap.

 

[wyrmrider]

The seat belt clip is hard- BVVC enlarging
longer bolt and a lock nut on the bottom without drilling the belt has worked for me