Morning all.

Has an interesting one yesterday. Took my 2013 Octavia 2.0 TSI VRS in for its mot yesterday, confident there wasn't anything wrong with it. Turns out I was very wrong! It failed on a snapped front offside suspension spring, and going by the amount of rust on the end of it, I'd say its happened quite a while ago. 

It's snapped at the top of the spring, so right up in the wheel well, and I'll admit to never checking that before. I've had a few rear springs snap on my old mk2 Octavias over the years, but never a front spring! 

Sadly, the story doesn't end there... 

I got a new spring (pair of) from Euro Car Parts thinking it'd be a fairly straight forward repair, boy was I wrong! 

First off, I couldn't break loose the front wheel bearing bolt. Bear in mind I fitted that a couple of years ago, and torqued to spec. 

Thought I'd work around that, so continued.

Got the brakes and brake carrier off with the usual fight given the amount of aluminium corrosion in the bolt holes in the steering knuckle (foreshadowing!) Got the anti roll bar links off, but they fought me too, the allen bolt hole has seen better days, (I'll replace that while I'm on). 

The suspension strut bolt however was another matter. Got the nut loose just fine, but the splined bolt itself was crazy tight. Without checking assumed it must be threaded through the knuckle (silly me). 

Got my big breaker bar out to get it loose, and the head sheared off!! This is an M14 splined bolt, so not small at all! 

The amount of aluminium corrosion must be mega inside that hole... 

It makes me annoyed once again that car manufacturers have opted for a cheaper, lighter material that isn't well suited at all to a climate that needs roads salted every year. 

 

Anyway, now I'm gonna have to drill out and replace the offending bolt. 

 

A few questions then:

 

Does anyone know where I can get the bolt from? Autodoc just seem to sell replacement nuts. 

What can I use to protect the inside of the bolt holes? Is copper slip OK for this application? 

If I ignore the wheel bearing bolt for now and take the drive shaft out of the gearbox, will I let the oil escape? 

3 hours ago, jimbojames said:

 

A few questions then:

 

Does anyone know where I can get the bolt from? Autodoc just seem to sell replacement nuts. 

What can I use to protect the inside of the bolt holes? Is copper slip OK for this application? 

If I ignore the wheel bearing bolt for now and take the drive shaft out of the gearbox, will I let the oil escape? 

It wasn't your day yesterday. I hate those days. Wish you'd never started.

 

Spectators complaining you said the job would take 1.5 hours. Etc etc.

 

A few responses.

 

1. The strut pinch bolt? The bolt will be a dedicated vag bolt N number. I'll look up for you. If you want in a hurry dealer or vag bolts on ebay will sell them but obviously, post has been slow slow of late. Pretty sure I kept my old ones. Not that you are supposed to re-use. 

 

2. Not sure you can protect. Any chance you could drill in a screw extractor, they Tighten in reverse direction. But bit concerned you would also break that. You reckon it is on corrosion. Have you sprayed penetrative oil?

 

3. At the gearbox end the drive shaft just ends with a blanking plate once you remove all those bots and joining plates, no?

 

Fwiw, when  pull out front struts I use the 2x4 method. It is frowned on by some but in the driveway with limited tooling I find it the most efficient least likely to run into a problem method. I don't remove wheel bearing bolts, only the strut pinch bolt, sway bar drop link bolts, strut upper bolts. Everything else stays put. You do have to get the lower hub assbly at quite an angle to clear the bottom of the knuckle but it will clear with help of wd40 and a soft mallet invaluable   

Edited 18 December, 20223 yr by TheClient
Typo

Just thinking a bit more. With that strut pinch bolt. A screw extractor may work if you can a largish dia screwed in then counter hold. And try to remove the nut end. The nut is a nylon lock nut from memory. 

Thanks @TheClient some great advice there. I very much like the sound of the 2x4 method for getting the strut out, instead of trying to take the whole hub assembly out.

 

I've managed to find the pinch bolt in autodoc, though it wasn't in the section I thought it would have been! Got two of them on order, as no doubt the other side will be the same. I'll just take more care and use far more penetrating fluid! 

 

I'm thinking for the stuck one, soaking in liberal amounts of penetrative fluid and using the nut to put a bit of pressure on it should possibly loosen it, failing that I'll give the screw extractor a go. 

 

I'm going away for a few days, then it's the whole Christmas/new year carry on, so I'll get back onto this in the new year once parts have arrived. 

 

Just glad I've got my land cruiser for winter back up! 

Remove the nyloc nut, replace with a standard steel one and tighten fully, hopefully you will have 6mm + of thread protruding, arc weld the nut to the bolt shank, the heat expansion will hopefully free the siezed bolt, wait 60 seconds for the weld metal to cool and the carefully apply forward and backward motion with a breaker bar to release the shank.

 

If it does not feel like it is yielding then spray penetrating oil on both ends as soon as its cool enough not to vaporise the fluid, leave overnight and try to remove again.

 

If you cannot get sufficient thread protruding to weld to then either use a thinner nut or a longer barrel nut or spacing washers and make the weld internally which is a lot harder but there are special welding rods for broken stud removal.

Ah OK, interesting stuff. I've seen welding nuts on many times in many YouTube videos, never been in a position to try it myself yet though, this may be the time! I've used heat before from my little propane torch, it just takes ages. 

 

Thanks @J.R.! 

Edited 18 December, 20223 yr by jimbojames
Typo

Heat from an oxy-acetylene torch would shift it, propane without an oxygen cylinder is just too slow and results in collateral damage, trouble is with the price of the gas and especially the cylinder rental and the democratisation of Mig welders very few people still have and use oxy-acetylene.

 

I handed in my remaining bent cylinders when I left the UK, I still have the Portapak that I bought in 1978 but doubt I will purchase cylinders for it here in France where its much more expensive than something that was already a silly price.

 

You also don't want to be heating up a  pressurised strut containing oil which will burn when vaporised.

Not quite sure I'm following which bits got you stuck? Is it the pinch bolt that clamps the hub assembly onto the shock that you're talking about? I'd personally normally take the strut out whole if I was changing a spring. You'll also want the release tool that opens the hub just the right amount. Whacking a chisel in can crack the sleeve on the hub assembly really easily. 

 

If you've got the nut off that bolt, I've give it a spray all over and let it soak overnight, then just knock it through with a hammer and drift. Worst case, put the air chisel on it. Don't use heat that close to a shock absorber. 

Glad I'm not the only one.... Pinch bolts were a nice and stuck... Hitting with 4lb hammer not shift it... Nightmare.... Top bolts on engine bay snapped off the top mount when trying to remove...

Edited 18 October, 202518 Oct by Richard80945

same problem with top bolts as one of them was badly corroded and decided to sieze. Ended up angle grinding them off. I'm sure I didn't have this much bother on mk2 octavia.

Ive done shocks and springs on various cars... Peugeot.. Vauxhall. Citroen... Nissan..... Never have a car give me as much hassle as this skoda... Corrosion... Access

Wow, no doubt this is all due to the steering knuckles being aluminium alloy, and was me thinking that I'd change the weeping/leaking front dampers on my older daughter's 2019 SEAT Leon Cupra - which like the VRS will have alloy knuckles!

I'm still recovering from this horrible "steel bolts in aluminium parts" after replacing too many bits on my 2011 Audi S4, a truly horrible job that got bigger and bigger and bigger - and so a lot more expensive ending up with me throwing the towel in with a car "now off the road" due to a seized then shearing lower pinch bolt on one upright, a rusted wheel bearing assembly that was eating ABS sensor on the other upright - that annoyingly, I had managed to get the lower pinch bolt out of the other upright before this - so wallet took a hammering in and I just ordered in 2 new uprights.

I've still got the original aluminium uprights in the garage for when I feel up to the challenge of convincing the really really nasty long pinch bolts that they should just come out - really now just an exercise for me proving that given time, I can do it. Getting the wheel bearings out is also a tricky job, but I have now removed one of them, again just to prove that I could do that - and putting into use tools bought specifically to do that job on the car.

I used a lot of PB Blaster, used blu tac to create bunds to hold/store PB Blaster around the affected areas, using an induction heater a few times, used an air hammer a lot, used a Mapp Gas torch as well, a long and not very satisfying job during the summer months - really leaving a lot of time for the PB Blaster to do its job in between the air hammering, induction heating and gas torching. One point, blu tac, after being in contact with PB Blaster is horrible stuff to handle and once the PB Blaster breaks through your blu tac barrier due to poor application, nothing much will seal it back up other than removing the blu tac and applying a lot more new stuff!

One problem with the pinch bolts, I think, is, they are all very low strength bolts, so 8.8 as they only get torqued up to a very low figure to do their job - this ends up being a bit annoying when you need to get them out from aluminium lumps that have corrosion in these bolt holes, I used aluminium grease on all the new bolts and tried to seal up or close the pinch areas to try to hold back future corrosion.

Luckily for me, the pinch at the bottom of the front dampers on B8 Audi S4 and others is steel, so easy to remove that pinch bolt tap it out and open the pinch area with the usual VAG "hub expander" without worrying about cracking any aluminium parts - same when working on Polo and Ibiza.

@Richard80945, One bit of advice when handling aluminium knuckle pinch areas, maybe a good plan to make up shims from halved washers to fill the existing pinch gap - doing that should stop you ending up cracking the aluminium "lugs" of the knuckle.

If I had known or experienced what I have now concerning this job, I would have headed straight to the stage where I bought in 2 new uprights, yes very expensive but I would not have felt the need to buy an induction heater, new hub puller/slide hammer, new gas torch or new hub press tool - but really, after you've had time to reflect - where is the fun in doing it that way? Mind you it would have freed me up to do many other household maintenance jobs and use my S4 to go away with my wife!

Edit:- I did try drilling into the soft sheared bolt - sheared off cleanly exactly where the shank changes to the threaded section which was exactly inline with the "lug" that the threaded portion passes through before exiting to where the nut gets screwed onto. While the Audi B8 S4 upright was still on the car, access was tricky, made worse by the fact that this model of car does not have "free to rotate" struts, the front suspension is 4 unequal alloy arms with bonded bushes, so the tendency is for the steering to self centre rapidly when you take you hand off the steering wheel, not very handy/helpful when working on this model of car!! I ended up needing to buy longer drill bits and try to drill through "from the other end" using the sheared off bolt with a pilot hole drilled down through it as a guide - well that did not help me achieve what I needed to so drill wandered off and so my new set of "easi outs" did not get used - my plan was to use "easi outs" instead of normal bolt extractors so that I would be applying an "unscrewing" action to the sheared off part of that bolt, but not getting the holes perfectly in the centre obviously destroyed that plan and an upright!

Edited 20 October, 202520 Oct by rum4mo