I'm overseas at present but when I return home I need to strip down the front brakes and probably replace the disks on a 2013 Fabia 1.6 CR TDI Estate. Long story but the car was left for three months covered in salt after a long winters drive and it looks, from the info I have been given, that the front disks may have corroded or been scored.

 

Just wondering if anyone can confirm the size of the hex socket needed to remove the caliper bolts. I'm thinking it will be 7mm but grateful if anyone can advise. I'll need to order a 1/2" to hex  and would like to do that before I get back. Most of my main tools are overseas.

 

If you are on about the allen key bolts I think it is 7mm- I had to buy one for the job.

7mm as above

Thank you both. 7mm it is then.

I am just a this moment cursing whoever selected 7mm for these bolts when almost no allen key set includes a 7mm. I think they do it deliberately.  Meanwhile i am busy destroying the bleed nipple and assuming it ever comes out..(heat/cool/heat/ cool...tap tap tap etc) I have some new ones on the way. 7mm...who'd a thunk it eh !

The issue is with the company that designed these brakes, I had that issue many many years ago with Fords, though, without trying to be cruel "proper" allen key sets always include a 7mm key, my original toolkit did not include a proper allen key set so I had to buy a 7mm at an industrial supply shop.  Nowadays more, even DIYer allen key sets include a 7mm - probably due to the increased use of that size.

 

I have a smallish metal worker's vice, so maybe I used that to get a really good hold of these brake nipples that had seized in the callipers. That vice has a fierce grip and not much in the way of leverage so forces you to "go easy but firmly" with the stubborn bleed nipples.

On 18/05/2018 at 13:08, alfalincs said:

I am just a this moment cursing whoever selected 7mm for these bolts when almost no allen key set includes a 7mm. I think they do it deliberately.  Meanwhile i am busy destroying the bleed nipple and assuming it ever comes out..(heat/cool/heat/ cool...tap tap tap etc) I have some new ones on the way. 7mm...who'd a thunk it eh !

 

Car servicing made easy is all about the proper tools.

 

A 7mm brake allen key is only four quid from ebay. You would not be able to use a standard allen key because you cant get enough leverage as the long end needs to go in the caliper.

 

https://www.ebay.co.uk/itm/Draper-Expert-Brake-Pad-Hex-Allen-Key-with-Handle-7mm-68425/132596753665?epid=1105443894&hash=item1edf61e501:g:8J4AAOxy4YdTUaUh

 

https://www.ebay.co.uk/itm/CT2120-7mm-Long-Reach-Hex-Allen-Key-Bit-Socket-H7mm-X-125mm-Suit-Brake-Caliper/372229866122?epid=16017007500&hash=item56aaa1028a:g:OZEAAOSwjIVacFoQ

 

Use a good quality 11mm ring spanner for the bleed valves. A little penetrating oil on the threads left for half an hour if you must.

 

58 minutes ago, xman said:

 

 

 

Use a good quality 11mm ring spanner for the bleed valves. A little penetrating oil on the threads left for half an hour if you must.

 

I had to smile at that as these 16 year old seized in bleed nipples showed clear fresh air all round when an 11mm ring spanner was introduced. A 10mm actually just fitted on these much abused items..just, so they were effectively rounded off a long time ago. No amount of penetrating oil (as in left overnight) was going to shift these. It took heat/ penetrating oil/ ice cubes repeatedly, and after about an hour or so..each...the nipples shifted with the help of big nasty grips. As it happens the post lady arrived with a new set of bleed nipples exactly five minutes after I had got the second one free as I knew the outcome was not going to look pretty. It looks great now though, so I have new hoses, nipples and ARB bushes in now. Still plenty more to do though before it returns to MOT land. New brake caliper slider pins are on order, and I found a 7mm Allen key that might just do the trick on an old set I had from CK tools.  I'm getting there slowly but surely. Bear in mind that up to me starting this job the car has always been garage maintained, and its only 16 months since they did new discs and pads. I only took this on due to the quoted cost of getting it fixed for MOT relative to the cars value.

Edited 20 May, 20188 yr by alfalincs

On 5/18/2018 at 21:54, rum4mo said:

The issue is with the company that designed these brakes, I had that issue many many years ago with Fords, though, without trying to be cruel "proper" allen key sets always include a 7mm key, my original toolkit did not include a proper allen key set so I had to buy a 7mm at an industrial supply shop.  Nowadays more, even DIYer allen key sets include a 7mm - probably due to the increased use of that size.

 

I have a smallish metal worker's vice, so maybe I used that to get a really good hold of these brake nipples that had seized in the callipers. That vice has a fierce grip and not much in the way of leverage so forces you to "go easy but firmly" with the stubborn bleed nipples.

In an ideal world I'd have all the right tools and not have to work on cars on the 5 degree slope of my drive, which is not always fun. I can but dream.

I don't know why garage mechanics seem to always over tighten everything 

Hum sloping driveway - challenging/dangerous with wheels off the ground!  The bleed nipples "dropping" a size, yes they do don't they that was why I added my "small vice" method, when I found that had happened to the front ones on my daughter's late 2009 Ibiza, I was lucky as a new pair that I had previously bought and never used, fitted just fine - maybe not as long as the originals but as long as she trades in that before I need to change the fluid again, things will be all right!

 

As I get older I still seem to buy more garage tools, even bought another galvanised tool storage box to tidy up the garage a bit - really to keep any "not normally needed" tools out of the way!

 

Edit:- I think that replacing the brake fluid every 2 years and keeping these areas clear of crap, then using a wire brush on them followed by some brake fluid to soak the rusty area does make slackening them off a bit easier, it will be the time and corrosion that will have caused them to seize I'd expect and not over tightening.

Edited 20 May, 20188 yr by rum4mo

1 hour ago, xman said:

I don't know why garage mechanics seem to always over tighten everything 

 

The tightest things I have had to undo recently were factory/machine tightened and that was the caliper bolts on my 2014 Octavia. Things were NEVER quite that tight on my Peugeots and Alfas. When I did the Octavia Discs last August it actually snapped the swivel on the tommy bar on my socket set. OK...so the socket set has done sterling service since 1975...but even so, The new tommy bar was about 14 inches longer.......and did the trick. It was me that was knackered by then

 

And another thing.....Alfa used to supply a big red screw in pin to hang the wheel on while you were replaced the wheel nuts. It made the job of getting a wheel back on a doddle. I wonder why nobody else has cottoned on to this.

 

Laugh a minute this car...just found out the rear passenger window doesn't wind down, but if you force it down it will wind up again...

Edited 20 May, 20188 yr by alfalincs

You can buy one of these screw in pins from VW Group dealers, my old Passat and so probably Superb had a black plastic one in the tool kit, I bought one for my wife's Polo to help if we get a puncture, for use in the garage I bought a longer and stronger aluminium one as supplied with the big VW 4X4 and probably similar Audi big 4X4.

 

Here is what I have logged as being the one I bought for wife's Polo :-   893 012 223   

 

Edit:- while I'm at it, the stronger aluminium version from VW or Audi is 7L0 012 223, costs more though.

Edited 20 May, 20188 yr by rum4mo

firstly i like to apologise for resurrecting an old post.

 

secondly i just had this problem, i wanted to change my front dust shield but like the op, i had to order the 7mm allen key, i can always wait till that arrives but im struggling getting the little screw out that is on the hub.

 

anyone got any ideas on how i can get that out please?

 

thank you

2 hours ago, froggy8 said:

firstly i like to apologise for resurrecting an old post.

 

secondly i just had this problem, i wanted to change my front dust shield but like the op, i had to order the 7mm allen key, i can always wait till that arrives but im struggling getting the little screw out that is on the hub.

 

anyone got any ideas on how i can get that out please?

 

thank you

If it has rounded out, a drill is your best option if you're careful. I had to do it on my Superb last year after the head snapped off (probably cross threaded by whoever did the job previously). Start with a 2.5 mm bit and take your time.

4 minutes ago, chimaera said:

If it has rounded out, a drill is your best option if you're careful. I had to do it on my Superb last year after the head snapped off (probably cross threaded by whoever did the job previously). Start with a 2.5 mm bit and take your time.

yeah just like the op, rounded off inside 😞

 

thank you, will try that.

Try a centrepunch and hammer near the outside of the head first. 

Knock it in straight to get an indent, then use that to knock it anticlockwise. 

2 minutes ago, Wino said:

Try a centrepunch and hammer near the outside of the head first. 

Knock it in straight to get an indent, then use that to knock it anticlockwise. 

ok il try that first, thank you  

Yep centre punch or if you are really lucky to find one a diamond pointed chisel (not real diamond but the shape) which is made for the job, someone stole mine yonks ago.

Just drill the head off....assuming your talking about the disc securing screw ?

yep its just the disc securing screw.

just drill the head off then, one the disc is off the remaining threaded part will come out easy.

thank you guys, as soon as the allen arrives then il do it all at once.

As an aside here, going back to the comments about using a 7 mm head on the bolt, the ISO standard that defines the metric thread series defines a formula that links the tool size to the thread size, so it's likely that the reason for the odd sized head is that the engineer designing the part wanted to use a particular thread size and the head size was locked in by that. It's always possible to make custom fasteners as well, but that can have cost implications.

They are not standard fasteners, the closest that they would come to would be a toolmakers shoulder screw without the head and a recessed hex socket within the shoulder diameter.

 

The outside diameter would have been calculated for the desired rigidity, an 8mm hex would leave the wall thickness too thin, a 6mm one would risk breaking the tool so 7mm it is.