Top harness mounting bolts

[Daxman]

Hi Guys,

I just been trail fitting the willans harness supplied by dax, in the manual it states the bolt length should be at least 1 3/4" in length. However the bolt supplied is only 1 1/4" long. This means that by the time the bolt has passed through the rear stay and the body there's only a coouple of threads engaged in the chassis.

Not a problem i thought, just order some longer bolts. but none of the bolts have "8.8" Or "S" on them, which i believe is an SVA failure. The bolts do have Three lines on which i believe is the ISO equivilant, is this OK.

If not does anyone know where i can get some correctly marked bolts.

Many Thanks,

Russ

[JonnyT]

Hi Russ,

Can't remember whether the bolts were Dax supplied or supplied by Willans I'm afraid but what I do recall (because they were such a pain in the ar** to get in) is that the bolts supplied fitted fine once the rear stays of the roll hoops had been persuaded to line up with the chassis.

I suspect that you have the wrong bolts supplied by Willans or Dax. Worth being spot on on this point as the SVA inspector was very particular about these bolts on ours (evidence that it all came from Willans etc). I suspect only because they are very obvious on the test.

Jon

[madjohnny]

The bolts supplied that I had were fine. The tensile strength on imperial bolts is marked using lines on the bolt head. Basically the more lines the higher the tensile strength. See here

I printed something like this out and took it along on my SVA and the examiner was fine with that.

[DFitton]

Hi, The SVA man did not check my bolts for the markings. all he checked was the height of where the harness bolts to the roll bars and the seat. They must be lower than an average shoulder height. I did have to get longer bolts to fit them and they were marked with an 8. Good Luck.

[Marc]

Hello Russ,

I did have the same problem!!

The bolts supplied were to short and I replaced the with some bolts we use in the hydraulic business (internal hex). When I went to Southampton for SVA the Inspector queried me about the bolts and strength. I told him that they are equivalent to 10.9 as that is the min. requirement on hydraulic application. He went to check and came back with some print outs.
The marking you are mentioning also indicate the strength. Surf the internet and take some data sheets about the bolts with you.

Marc

[Nobby]

Russ, Dax also supplied me with 'S' marked bolts that were too short. I got some replacements from AHC in Camberley - should be able to get them from any good tool supplies company though.

The roll bar round tubes didnt slide all the way into the chassis brackets on one side. Turned out there was weld spatter inside the tube preventing it from sliding in all the way. An absolute ar5e to remove as it was 4 inches inside the tube.

The seat belt bolt holes in the hoop stays didnt line up on mine either (most of the bits on the car didn't). Tried bending them to fit but no joy. In the end I elongalted the stay holes by 10mm and all went together OK.

God bless Dax.

[JonnyT]

a judiciously applied ratchet strap around the three legs at the bottom persuaded the bolts to go in on mine!!

[Nobby]

Originally Posted by JonnyT

a judiciously applied ratchet strap around the three legs at the bottom persuaded the bolts to go in on mine!!

Jon, Sounds like Dax need to adjust their roll hoop jig as they're all out of line. I tried levering the bars but couldn't get them to line up.

Oh well the pain is receding now. I can laugh at all the problems during my build Well I could but I took it all apart again for paint and engine upgrades etc. Some people never learn.

[craggle]

Originally Posted by Nobby

Jon, Sounds like Dax need to adjust their roll hoop jig as they're all out of line. I tried levering the bars but couldn't get them to line up.

Oh well the pain is receding now. I can laugh at all the problems during my build Well I could but I took it all apart again for paint and engine upgrades etc. Some people never learn.

My Guess is they move during Chroming and polishing and not whilst on the jig being welded.
I guess I got lucky with mine as they both lined up perfectly.

I think the bolts that are supplied with the seat belts are from Willans. I seem to remember there was two longer bolts of the correct grade in the Dax nut and bolt kit. They are the ones I used and they passed fine.

Craig.

[Daxman]

Thanks for all the replies, The roll hoops were actually a good fit and the bols lined up perfectly, I have found a comparison chart for metric and imperial markings, it would seem the bolts i have with three radial lines are equivalent to a 8.8 bolt. so if i print this off and take it with me to SVA would this satisfy the tester?

Bolt Grade Markings and Strength Chart

Thanks again

Russ