Seat Rails Nut Stripped?

[ChargedAutoGT]

if it is stripped, tap it to M8 - metric, or if if it's too far gone could go to 3/8 or 10mm.
G

[nathan_f]

Good idea. That should prevent having to drill it out more, right?

[Ian F]

Nathan,
you might get away without any drilling but to do the job properly you should use the specified drill size for any re-tapping of a hole. This is particularly important if you are using a DIY tapping set, which might not cut a thread as easily as a professional tap would.

Ian F

[nathan_f]

Got it, thanks!

[nathan_f]

So drilled out the bolt hole and tapped it to M8 1.25. Got the carpet, insulation, shims, and seat positioned back in the car, went to tighten down the bolts...and the bolt (which I had previously tested in the hole and appeared to be good and tight) just started spinning after I got it snug. Presumably when I tightened down the bolt, the harder steel of the bolt stripped the threads which were probably just in the soft steel of the floor board anyway.

Unless anyone can think of a really horrible reason not to do this, I'm going to drill down and through the crossmember and put a M8 100mm stainless bolt all the way through secured at the bottom of the crossmember with a nut and washer and then sealed with some silicone. I figure that having the bolt in place will help return at least some of the structural integrity of the crossmember that might be lost by drilling the hole into it.

[Ian F]

That's very frustrating Nathan, and a great pity it didn't work out. For myself, I would be content to do as you suggest, and even make the hole large enough to fasten directly below the floor. The hole left could be sealed with a grommet.
Just check underneath to ensure there are no cables/pipes in the way.

Would be good to hear from other contributors if they agree with my position on this. I suspect they will as the BGT body shell is somewhat over-engineered and very strong.

Ian F

[Tom Brearley]

There are already several drain holes in the chassis members of around 8mm diameter. The same is true of the castle rail. So I wouldn't personally be too worried about making a new, larger, one.

[ChargedAutoGT]

you can buy M9...
G