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NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 7:13 pm
by Luke
Hi Guys

Was making me up a bracket to bolt a fire extinguisher to bolt under the passanger seat bolts, and of course I have cross threaded one of the holes!!!
The bracket changed the angle the seat sat at so of course I bolted straight down, probably didn't help that I did it at night with poor lighting. I'm pretty sure it is only the first 2-3 thread though.

So was wondering what the spec of the thread is.
My internet searching says M10x1.25, but it is always for a NA. I can't imagine a NB being different but just want to check.
Plus the bolts are definetly 10mm wide. So I know the M10 part is correct at least.

Next step borrow a tap, hopefully I will have one at work somewhere, but I don't think we have any that big.

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 7:22 pm
by NitroDann
Take the bolt into work/nut and bolt place and ask??

Dann

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 7:23 pm
by zossy1
NA and NB are the same. M10x1.25mm sounds right...

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 8:07 pm
by Lokiel
zossy1 wrote:NA and NB are the same. M10x1.25mm sounds right...

Confirmed - I had to retap some on my SE and that's what I used.
Tip: ALWAYS hand tighten seat bolts as much as possible first, it's way too easy to strip those threads.

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 9:01 pm
by Luke
Yep really easy to strip. The metal is quite soft.
At first I though the bolt was grabbing on the holes in my plate because the holes were only 10.5mm, but yeah.
I've taken the drivers side seat in and out countless times, and finally have to do the passenger and bugger it up lol.

Anyway, thanks for the confirmation, I'll check what I've got available at work, but if I don't have it my dads workplace should have it.
Otherwise off to the tool shop.

Odly the workshop manual I downloaded a while back specifies the torque, the head size, but not the pitch.

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 9:06 pm
by marty085
Where can I get these bolts with the necessary strength? Any decent hardware shop? I want to replace mine as they are the shallow head variety with tapered edges mentioned in the Miata Enthusiast Workshop Manual as being right b!tches. I have already come close to rounding them so only want to take them out one more time and replace them with something half decent.

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 9:08 pm
by NitroDann
High tensile bolt shop.

Dann

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 9:19 pm
by Luke
I rounded my first set on the drivers side using a normal socket after changing the seat in and out multiple times.
I bought another Mazda original set (can't remember the price).
This time they are rounding much slower though, as I am using an actual hex 6 point socket rather than the multipoint one. Just seems to grap the bolt head nicer with the 6 point.

I kept the packet from when I ordered them with the old bolts in them incase I ever stripped one.
The part number is: 9YA0 21079
And it says Made in Japan.

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 10:24 pm
by Lokiel
marty085 wrote:Where can I get these bolts with the necessary strength? Any decent hardware shop? I want to replace mine as they are the shallow head variety with tapered edges mentioned in the Miata Enthusiast Workshop Manual as being right b!tches. I have already come close to rounding them so only want to take them out one more time and replace them with something half decent.


With my MAZDASPEED seats, I had to replace an OEM bolt on the rear outside corner of both seats because the OEM bolt head is too large for the brackets - the bolt would have to be forced in at an angle which is BAD.

I found that all the big retail car places, Autobarn, Repco and Supercheap stock the required high tensile 10x1.25mm bolts.

If you round these off then "You're doing it wrong!".

NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 11:09 pm
by marty085
Thanks :D I'll check out both Mazda genuine and an auto shop!

Re: NB Seat Bolt Thread Size

Posted: Wed Apr 04, 2012 11:26 pm
by Aussie Stig
I did the same thing on the pass frt left, these suckers are easy to muck up. :shock:

Re: NB Seat Bolt Thread Size

Posted: Thu Apr 05, 2012 9:19 am
by Luke
Bugger, biggest we got at work is M8 for taps, and all our 10mm bolts are 1.5mm pitch.

Re: NB Seat Bolt Thread Size

Posted: Thu Apr 05, 2012 9:48 am
by Regie
marty085 wrote:Where can I get these bolts with the necessary strength? Any decent hardware shop? I want to replace mine as they are the shallow head variety with tapered edges mentioned in the Miata Enthusiast Workshop Manual as being right b!tches. I have already come close to rounding them so only want to take them out one more time and replace them with something half decent.



Nice and close to us Marty

http://mobile.yellow.com.au/external/bd ... xt=unknown

Re: NB Seat Bolt Thread Size

Posted: Thu Apr 05, 2012 8:59 pm
by Mr Morlock
you buy bolts at a specialist fastener supplier - they can identify the bolt spec including grade etc- they can also supply taps. Mazda should also readily be able to supply a bolt.

NB Seat Bolt Thread Size

Posted: Thu Apr 05, 2012 9:11 pm
by marty085
Cheers! And thanks for the link Regie I'll check it out mate