upcoming NSF airbag replacement (arnott gen 1)

[mrnice.]

Hi, Im finally getting round to doing my replacement NSF airbag and just wanted to know if there was anything to watch out for? Ive read the arnott fitting guide https://www.arnottindustries.com/fil...466&Size=SMALL but know too well that the simplicity of a guide rarely translates into real life.

Is it a purely mechanical procedure or is there any kind of software required to reset the system?

Thanks.

[Alski2009]

I have to do my NSF too. Just be careful you don't crush the big o-ring at the top that sits under the aluminium hat. I'm having a nightmare trying to source a replacement.

Before you do anything put in level 4 and jack mode. Undo the VOSS brass airline fitting into the shock and let the air escape. With a little wiggling you won't need to undo the lower ball joints.

Looking at the old and new VOSS fittings, they look the same, but i couldn't risk the old fitting not working with the new Arnott airspring. If you have time then maybe you can check them carefully and ommit the next bit.

If you're careful, you won't need to cut the VOSS airline fitting off as you'll shorten the length of the plastic airline by 1inch. Unscrew it from the airspring. Slide the neoprene rubber cover up a bit. Hold the outer brass threaded fitting and push the airline through say 10mm. You'll see the inner brass split clip move forward, slowly pry it off and keep it someplace safe. Now slide the threaded brass fitting off with the rubber o-ring. You get new fittings with the Arnotts, it's always good to have spares. Don't ask me how i know, just be careful when you tighten the Voss fitting into the Arnott, it's the little rubber o-ring that seals the system. Just tighten it a smidge past the point it squeezes the o-ring.

Remove the lower control arm bolt, support the brake disc/wheel hub, undo the pinch bolt, gently tap the upper control arms out, then slightly undo the 3 big bolts in the engine bay. Now get someone to hold the shock and compress it upwards, while you remove the 3 big bolts. Slowly slide the whole lot out.

The rest of it is easy. Follow the instructions you get in the kit. You'll need an XZN bit for the 6 bolts that hold the Arnott to the aluminium top mount. Don't over tighten them, or you'll be looking for a replacement oring like I am. The bolts on mine were so rusty i used up an entire can of GT85. Eventually got enough of the XZN bit inside and drove the bastid bolts out and chucked them in my neighbours garden whilst doing a celebratory jig. You will have 6 new bolts in the kit. Smear a littlle white lithium grease on the big oring on top of the Arnott before fitting, you may need to rub down the mating surface of the aluminum mount with a little wet and dry to clean up the oxidised ally.

If the upper control arm bolts haven't already been reversed, do it now, so you won't need to strip it all down to change the upper control arms. Don't ask me how i know. I need to do this too. You'll see what i mean when you tackle this job. Such a typically Audi thing to do.

Don't forget to compress the shock when refitting and just snug up the 3 bolts in the engine bay. You'll need to support the lower control arm with a jack to run the bolt back through. If you're having to screw the bolt in, you're not doing it right. Wiggle the shock a bit and then the jack and it'll go back in nice. The guys in the US suggest tightening up the 3 big suspension bolts when the car is on the ground. I didn't do it this way and my camber was way off. Ideally you should tighten all the suspension bolts and bushes when on the ground in Level 2. If you don't your arms will squeak a few months later when you rip the spider arms inside your expensive bushes. Don't ask me how i know. Make sure your level sensors are in-place on the little detents.

When you're refilling the system, use a jack to hold the car up so it doesn't crush and fold the airspring, now cancel jack mode, set it for level 3. If you feel the airsprings now they will be soft, the sensor needs to detect a change in height before it will fill with air. Lower the jack a little and it will pump up with air. Now remove the jack. Don't worry if 1 side is in the air and the other on the floor. Cycle through Level 4 - 1, then up to 4 again and everything will be hunky dory.

How are you tightening the 19mm suspension top mount nut? Allegedly it's 50Nm. No way will you achieve this with a ghetto adjustable wrench and an allen key in the top of the strut on the floor. You need a go-through socket. Halfords do their Vortex set.

Again i need to do this myself very soon. All the steps above are from memory. I have 4 new genuine Audi shocks to go on. I hate the way her **** wiggles when i'm pushing hard through the bends. Crap. The genuine Audi front suspension rebuild kit is £75 (for 6 XZN bolts, 2 orings, a thick metal collar, a 19mm nut and the rubber mount). The only thing that wears out is the rubber suspension top mount bush. Mine had started to delaminate, hence the knocking over badly surfaced roads. Save your money or buy me an expensive 'coffee-bean-eating-cat-poo' coffee, and buy a mount for cheap on Ebay for £23.

Good luck getting that pinch bolt out. It's a nightmare, i would start spraying the bolt with penetrating fluid ASAP. As tempting as it is to drive a chisel in that gap, only do it if its really seized.

[bagpipingandy]

Good luck getting that pinch bolt out. It's a nightmare, i would start spraying the bolt with penetrating fluid ASAP. As tempting as it is to drive a chisel in that gap, only do it if its really seized.

dont chisel the gap to spread it, you can snap lug off leadng to a new strut, it is not the gap movement causing the bolt to stick it is just good old fashioned rust, if it is stuck you need to clean and clean and squirt with loosening agent and soak leaving it to penitrate, repeat until it give in, it takes time but should come loose, dont be fooled this can be the hardest part removing the 1st bolt!!

regards

Andy

[mrnice.]

wow thanks for the comprehensive reply! Im glad to see I havnt got to hook her up to any software mainly because I havent got any yet and money is tight at the moment.

Has anybody got any idea as to the size of the XZN bit? as Im considering buying just the single socket (or small pack of) instead of the full kit if the price is a lot lower (£20 for the kit is tempting but as mentioned earlier Im trying to keep costs down as Ive just done a full service + cam belt, pullys, idlers, belts etc).

Also Ive been trying to find the suspension top mount that you mention but I can only find this one: KYB Front Left or Right Suspension mounting kit/Top strut mount SM1712-KYB | eBay for £33, could you point me in the direction of the cheaper one please? (I've found the bush for the 2.7 for £17?!?)

One last thing: can you fit go through sockets to a regular torque wrench or does the vortex go through socket set come with a torque wrench? Im a little confused as how to how to nip it up to 50Nm?

Thanks.

[Alski2009]

That's good advice from BagpipingAndy. I keep meaning to pack the joint full of copper grease and wrap it up in a 'rubber' to keep the filth out. It's a huge job to replace it (you have to remove the driveshaft, CV joints, balljoints, ABS ring and sensor (have i put you off yet?)). So take your time with it. Spray a little lube, try to move it a little then tap it a bit. If it is properly seized and you have access to an impact driver, you can zip the head off and tap the bolt out. Just be mindful that you're obviously tightening up the bit you're trying to undo. For the average enthusiast mechanic that doesn't need cars to be in and out in 30mins, just take your time.

Err. You should have a new strut mount in the Arnott kit, along with 6 replacement hex bolts (not OEM XZN) and 2 orings (one is already installed inside the airspring). The reason i mentioned it was to prevent you wasting £75 + VAT, per side, buying the suspension rebuild kit from Audi, when all you need if the rubber strut mount. If you don't need it in a hurry you can buy it from ECS Tuning in the US - Audi All Road 2.7T > Search > Allroad Strut Mount > ES#263706 Allroad Air Spring Mount Kit - Priced Each - 4Z7698507.

I will check the size of the XZN bit tonight. I'm sure you can Google it or go the long way round, find the part number for the bolt and then Google the size bit. If you're on a budget and have a Dremel, cut a decent sized slot into it and crack it off with an old screwdriver or a bit of metal plate held in mole grips. Arnott give you new hex bolts anyway.

RE: go through sockets. A picture's worth a thousand words. Passthrough: 21 Piece SAE/Metric Go-Thru Socket Set (Pittsburgh Item #67974) and Cromwell Industrial Tools UK: Kennedy Professional: 10mm GO THROUGH SOCKET. Note: most of the nuts and bolts on my allroad are rusted to hell. Standard sockets which drive the corners will round off rusted nuts and bolts with 1Nm of torque and then you're stuck. It's always better to drive the sides and get the rusted bits off and replace with new. The burly splines transmit up to 40% torque. If you only get one chance then use decent tools.

You can either go by feel. 50Nm isn't much, tighten till you feel it pinch and then a smidge more so it's tight, or maybe setup a little rig with some scrap metal to get a feel for it, or use a crowsfoot socket with your torque wrench. But now you're getting into torque multiplying and translating forces around a fulcrum which is beyond me.

[mrnice.]

I popped out briefly last night to take a quick look at the job with a handfull of six sided hex spanners, , the 16mm pinch nut bolt freed up straight away!

The bottom shock bolt - does it need an 18mm or is it an imperial size?

Whilst poking about I also noticed that the CV boot had also torn - hooray! - so thats another little job to get on with at the same time, I noticed they now do "easy fit" boots that dont require the removal of the drive shaft or CV joint, they carry a 2 year warranty like the OEM ones and are apparently "of OEM appearance and quality" has anyone any experience with these boots?

Does the the axle bolt require a regular female 17mm hex socket or a male "allen key" type 17mm bit to crack it? Havent had chance to check it as shes gone out in it.

Thanks.

[bootie3367]

Nice write up and thanks for the tools links. I have a feeling that I may be doing this on my son's car in the future so I may as well get the tools required now and possibly start collecting spare parts as I go on.
Unfortunately he doesn't have time to do this sort of work, self employed and needs to work all the hours there are. whereas me, I can take my time whenever I go visit.

Jon

[Alski2009]

What a relief the pinch bolt came off easily. There are videos on Youtube of people using a gas torch to heat up the metal to break the rust free. Count yourself lucky and buy your wife or girlfriend or boss an inappropriate gift to maintain world order. If the bolt's in good condition you can re-use it. It's only there to hold the upper arms in place. I'm planning to change the front subframe bushes and due to the amount of torque needed to tighten the stretch bolts, i will probably buy new ones. By all means, read and listen to people's suggestions and the Audi maintenance manual, and apply common sense to everything you read and do.

Back when i did this the 1st time i didn't have proper tools, i used an adjustable wrench and an imperial socket on the lower shock bolt. I think it was either a 9/16ths or 11/16ths for the nut. I may be wrong. That go through socket is perfect for this job.

Damn. Busted CV boot. Remember apply common sense to your problem. Nearly always (for me anyway) shortcuts end up costing me more. And anyway, these things only exist for dodgy garages to do the job 3 or 4 or 5 times so you keep coming back for more. If you take your time, keep things clean, you can do it in a couple of hours, and you won't need to do it again. How's your wheel bearing? Maybe do it at the same time. You'll need a workshop press for that. Be sure to clean all the sand and gravel out of your CV joint. Horrible job that. Maybe pinch some non-alcoholic baby wipes from somewhere to clean it all up.

I got Chris (Adamss24) to do mine last time. He's great and nowhere near as expensive as the garage. I think the Qdrive CV boot kits come with a different grease now, it is much thicker like butter compared to the old one which was like washing up liqud. Have you got the CV boot clamp pliers? Get one with the little lump that prevents the extra metal from bulging up and over.

[Alski2009]

Decent tools make the jobs go smoother. Trust me when you have a go through socket set, you'll use it all the time. The only parts you need are the Arnott airsprings. They come with everything you need.

I genuinely believe allroad owners can extend the life of the airsprings by cleaning them regularly with a jet wash (gets rid of grit & gravel) and massaging lube into them. Mine have started to crack on the rear. I rub a little Vaseline on them from time to time to keep the rubber supple and it is holding out. The Arnott's are valved differently (a lot softer) than the OEM's. It feels so much nicer if you upgrade to an RS6 rear anti-roll bar with full OEM airsprings than Arnott's.

Wish my dad fixed my car for me. I'll be lucky to get a cup of tea.

[mrnice.]

If the bolt's in good condition you can re-use it. It's only there to hold the upper arms in place..

No its not looking too great and I was thinking of putting a new very greased one back in, wheres the best place online to get one (or 2 - I may have to do the other side at some point!)?

Ive had a look online but im not too sure which part number it is,

is it: n 034 790 7?

Re CV boot: I was curious as to these stretchy boots as opposed to those horrible split quick fit boots you can get, they carry the same 2 year warranty but I wonder if they actually wear out quicker/are as durable as the OEM product, as you say shortcuts normally lead to more time and expense in the long run. The wheel bearing seemed fine btw.

Oh and we've not long had a baby so I have HUNDREDS of wet wipes at my disposal!

These jobs are all coming along slowly but surely (with work and other commitments its hard to find the time).

Cheers again for all of your help guys.