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Seat belt bolt help!

cmcmill01

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Folks,
While removing my rear cargo barrier, I seem to have made a hash of the seat belt bolt and fixing.
Think I have cross threaded it and how it won’t catch at all to go in.
Any recommendations on a fix?
Thanks
Craig
 
Depending how bad the tread is try wrapping the thread with some plumbers whiter band (PTFE tape)
 
Re tap the hole. Should be M11-1.25 use tapered tap first. Is the bolt still any good? If not replacement bolt from a scrapyard.

M11-1.25 is virtually identical to 7/16-20 size.


Many moon ago I used to live in Bromley BTW. It's changed a lot since I lived there.
 
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I've had luck using an original size stainless bolt which is harder than the nut steel so kind of re-cuts the thread if you can get it to bite straight enough to force it in .
 
seat belt fixings use an odd but industry standard thread iirc. I cross threaded one of mine and to retap it after buying the right tap, can't remember of the top of my head what the thread size was though.
 
I did a similar thing with mine, for some reason it seems easy to do. Is it the bolt or the captive nut that is threaded? With a bit of luck it's the bolt that's knackered in which case you can just replace it.
 
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Thanks folks good to hear I'm not the only one to do this!!
How do you check the size and thread of a bolt?
Re tap the hole. Should be M11-1.25 use tapered tap first. Is the bolt still any good?


Many moon ago I used to live in Bromley BTW. It's changed a lot since I lived there.

Will go with the above, but both the captive nut and the bolt I think are done for, maybe see if I can get a 2nd hand bolt, although think about it I should have some spare bolts from removing the the 3rd row seat belts.
 
seat belt fixings use an odd but industry standard thread iirc. I cross threaded one of mine and to retap it after buying the right tap, can't remember of the top of my head what the thread size was though.
Hi Mark,

They are usualy M11 or 7/16, M11-1.25 is virtually identical to 7/16-20 size.
 
Do you have a vernier calliper? Best way to measure thread pitch is to measure as many pitches as you can and divide to get an accurate measure - don't try and measure one! Measure 10, or 20, or even better 30 and divide through.
 
11-1.25 mm is ~20.32 TPI 0.4331” and 7/16-20 is 20 TPI 0.4375” they are close enough to not be a problem if your careful, but your 80 being made in Japan should be 11mm, America wanted 7/16 to be the world standard, so now there is more than one standard. Similar to the screw heads on most Jap cars, you would think they are Philips or Pozidrive, wrong, they are JIS (Japanese Industrial Standard) go figure.

Every country want's their slice of the pie.

On some cars (not sure about the 80) you can access the captive seatbelt nut from the other side, so you could run a good bolt through from that side to try to reinstate the thread. Just a thought, no, didn't hurt.


Good Luck. :handgestures-finge: :thumbup:
 
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Well these are 11mm and 1.25 pitch. Incidentally metric threads are not measured in TPI. They're classified according to the distance between the thread essentially. so 1.0 is less coarse than 1.75 etc.

Do they look like this? This is a scruffy one but I've a few I think and some are like new. Personally I'd avoid re-cutting the thread if possible as that will remove metal. You're better to try to reform the thread with a bolt and a bit of technique really. I use thread restorers but you won't find an 11mm one that easily.

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