Firstly thanks again to all whom helped with my front ABS sensor fix around four or five months back.

 

So armed with my new troly jack and a tiny bit more confidence I'm looking for help with my next project: Rear drum brake overhaul on my Polo 6N2 1.4, 8 valve. Gonna need some new tools but hopefully they'll pay for themselves again!  Will do everything while I'm there so I'll never have to touch again: cylinders, shoes, springs and hand brake cables.

 

I can take my time with this so I am happy to go back and forth (and up and down) until I get it right. So forgive me all if I seem frustratingly slow at getting things done. Also, feel free to point out the obvious to me or anything I might not have thought about - thanks.

 

First a few pics and some starter questions.

 

1st Picture:

 

The back of the drum (bleed nipple on other side hasn't fared so well as this one!). Got an 11mm flare nut spanner and some "Security" Torx bits and was thinking firstly just to loosen these up and then re-tighten then I know I can get the cylinders out when it comes time and I can start getting parts in.  Was thinking: should I use some heat first, to save rounding anything, or is this a no no where the hydraulic lines are?  Do these flare nuts normally come undone first time?  Also regarding the torx bolt: the Torx bits I've got are the "Security" Torx with the hole in the middle of the star to receive a pin on the bolt head (like these:

 

) - does this matter? T-30 is a little slack but T-35 won't fit in (I'd have to really whack it) and hole is pretty corrosion free - should I try the T-30 first is there one in-between or is it the "Security" Torx that are different?

 

2nd Picture:

 

So the big question in my mind: to remove the bearing/hub or not.  Seems like a no brainer to remove but having a bit of a fragile lower back I'm a bit worried about how much leverage I need to get the hub nuts on and off (I have no air impact tools).  Think I read somewhere that new nuts should be torqued up to 175Nm and the most I've done is 110 on wheel bolts using my body weight downwards.  If I don't remove the bearing/hub then that bottom spring looks pretty tough but I'd plan to get some return spring pliers like these: http://www.ebay.co.uk/itm/Sealey-VS035-Drum-Brake-Shoe-Return-Spring-Pliers-Installation-Removal-Tool-/380902192580?hash=item58af8a35c4:g:YIYAAOxyedRTeeoE What do people think?
 

Edited 30 July, 201610 yr by nige8021
Tittle Amended

Soak the mounting bolts & bleed nipples/flare nuts with release fluid, don't use heat. I wouldn't use those "security" Torx as they are weaker than the solid ones, start off with the T30 if that rounds out you can then hammer in a T35.  Do not undo the hub nut there's nothing to be gained. That tool will help fitting the springs also there is a similar tool that's a just a hook on the end of a T handle.

Get new springs and the spring loaded fastners that hold the shoes onto the backplates.

Thanks Nige - appreciated as always!  Glad I don't have to undo the hub nut!  Have wire brushed and sprayed some of this stuff around on the drivers side for now: http://www.halfords.com/motoring/engine-oils-fluids/lubricating-penetrating-oil/wd-40-specialist-fast-release-penetrant-250ml.

 

Guess this is the T style tool: http://www.ebay.co.uk/itm/Beta-1410-M-Exhaust-Brake-Spring-Puller-T-Bar-Hook-Wrench-/151049183534?hash=item232b3ba12e:g:8MkAAOxy4dBRm09Y

 

Have lubed up that "wedge key" and can push it up but can't get it down once the drum is on - tried loads of pointy things!  Have just tapped it down, from the top, before the drum goes on and used trial and error - seems ok and hopefully when everything is new and clean I won't have a problem.

 

I'll get some new Torx bits and get a shoe/cylinder/spring set off eurocarparts - I have one local and I can drop stuff back to them if anything isn't right.  Drums look cheapest on Mister-Auto at the moment so will get them a bit later as their returns policy is harder work!

 

In the meantime I'll have a look at things on the passenger side and maybe try freeing the flare nuts off and the Torx once I get the bits.

Edited 24 June, 201610 yr by cosaw

A couple of points:

(1) You say that you are using a trolley jack, but have you got axle stands under the car? It is never safe to work with it supported only by a jack - I see that you have placed the wheel under there, which is always good practice.

(2) Many years ago, I modified a pair of pliers by simply putting a hacksaw cut in each of the gripping faces about 2mm from the top. These I use to grip the spring loaded washer that holds the shoe to the backplate.

Regards

 

Hi Caretakerplus - thanks for the advice.  Yes I've got axle stands and four wheel chocks too.  Thanks for the nifty tool idea also.

 

Progress: Flare nuts and cylinder retaining torx bolts sprayed with penetrating fluid.  Flare nut and retaining torx bolt loosened nicely on nearside and nipped back up.  Parts on order.

 

So a new query - I came across this by looking at the rear of the back-plate and then did a search online. Anyway a picture will help: https://www.google.co.uk/imgres?imgurl=https%3A%2F%2Fwww.mecatechnic.com%2Fphotos%2FPH27822.jpg&imgrefurl=https%3A%2F%2Fwww.mecatechnic.com%2Fen-GB%2Fbrake-drums-vw-polo-6n-braking~PO4-FRE-TAM-.htm&docid=KzS4Te3kBK17MM&tbnid=qjiPrux5kBdY-M%3A&w=475&h=400&bih=961&biw=1280&ved=0ahUKEwjT_abtg9DNAhVoCsAKHR4rCQQQMwgiKAYwBg&iact=mrc&uact=8

 

You can see there are 6 replaceable "Glide Pieces" on the back-plate - a great idea it would seem! The bits that wear can be replaced! So I thought I'd go straight through a VW dealer for these and they're about 53p each - a lot for a bit of plastic but quite affordable if I complete the job myself.  Has anyone come across these "Glide Pieces" instead of the usual steel raised points on the back-plate.  I was just gonna use some anti-seize on the back-plate but now I see the Glide Pieces are plastic I guess they need no lubrication?

 

And on that point of lubrication?  Do I lube up anything between the shoes/springs/back-plate/cylinders?  I've watched a lot of YouTube videos and it seems people just dry fit the components with the exception of the usual glide points we've talked about.  I've lubed up that wedge key cos I can't pull it down with anything once the drum is on but I guess a new clean one will work better.  What do you guys think about lubrication?

Edited 30 June, 201610 yr by cosaw

I've only ever used copperslip on any parts that are in contact with the backing plate, cross bar, wedge & ends of the piston

While I'm thinking what to do - here is an update.  I'm a bit stuck!

 

First photo shows that the top springs and cross bar can't get between the cylinder and the hub to take the shoes off as is.  That thicker back spring just won't go through whatever position I've tried.  I could take the cylinder off now but wanted to do that last (after having chance to clean the backplate up) so as to minimise leakage.  I'm afraid the springs and shoes may also make the cylinder get stuck too - if I tried to take that out first.  I'm gonna try on the new brakes if I can take the front, thinner, top spring off in order to separate the shoes and avoid having to pull the springs/crossbar through the gap between the cylinder and hub.  If I get the new cylinder off then I must be able to put the new cylinder on as I don't fancy my chances of freeing up the nipple on the old cylinder.

 

 

OK next photo.  Just a slight concern: one of the tabs that retains the bottom of the shoes looks slightly bent.  I did lever against this side with a screwdriver in order to get the respective shoe out.  I know that bottom spring is strong but I can't see I bent that tab??  Should it be a worry?

 

 

Thanks again to everyone in advance.

 

Quick update: Thinner front spring removed but did not allow shoes to be separated because of hand-brake lever locking to the crossbar.  Rain making it hard to work now so reassembly till better weather.  Think plan will just have to be: old cylinder off, shoes off, new cylinder on, cleanup (new "glide pieces" and hand-brake cable), new cylinder off again, new shoes on, new cylinder back on etc.!!

 

Further edit.  Sorry to keep editing the thread but as no responses yet and further 'progress', it just seems easier.  So everything got wet in the rain.  I reassembled, applied brakes and handbrake over and over to adjust wedge.  Got in the car and drove - the brake pedal seemed to feel different was my first thought and I got a little worried.  I kept it below 10 mph and the brake pedal felt like it had more assistance from the servo making it feel softer than usual.  It still stops, the reservoir has not dropped, the pedal gets hard before the car stops.  Did these tests: http://www.newtonnet.co.uk/coupe/service/webtech/iindex.asp@id=12476

and all is well there.

 

Will only know tomorrow when I take the drum off again if anything is leaking.  Wondered if me hammering around on the shoes (while still on the cylinder) had finally made the cylinder fail or wondered if the wire bag ties that I used to keep the pistons in had cut a hole in the cylinder rubber somewhere?  Maybe just freeing all the springs up and getting things wet and moving (for now!) just made things work better at the back and so the pedal feels different?  Anyway done some gentle driving on quiet roads and the car stops just as well as before.  Can anyone put my mind at rest?

Edited 15 July, 201610 yr by cosaw
More information.

OK - an update.  In a good place at the moment I think.  Had to take cylinder off to get shoes off.  Cylinder was gungy and wet under one of the dust caps so guess we got there in time.

 

Just breaking for lunch and tea now that the line is capped off with a rubber dust cover off a bleed nipple.

 

Think I was getting over anxious on the breaks when I put them back together yesterday.  They worked in every way they should but I could swear they felt different even though I hadn't cracked open the lines anywhere.  Maybe pounding about on the cylinder had let air in somewhere?

 

Back to the job then....

PLEASE TAKE THIS LAST POST AS THE CURRENT QUESTION THAT NEEDS ANSWERING.

 

(Update: If you don't want to read the whole story then - please take this last post as the most important to be answered in order to help.  Think I've solved most of my issues so far by trial and error.)

 

So this picture shows my current situation:

 

I have left one glide piece in to show you what they look like - presumably they're some sort of plastic.  My plan is to clean a bit more and see how some Hammerite smooth might help on those holes before putting the new glide pieces in.

 

So THE CURRENT QUESTION, is one of grease?  Yes I should have thought about this before now!!  I got the Copper Grease in and assumed I would use that.  But the more I've read around - as Copper Grease is petroleum based (I think) people are saying it shouldn't be used near rubber or plastic.  So the glide pieces appear to be plastic and there are the rubber dust seals on the cylinders where I'm supposed to lube the piston ends.

 

Options:

The sachet that came with the brake kit of: 'Drum Brake Paste' of which there is hardly enough to do the 12 glide pieces.

 

Some 'Red Rubber Grease' on all lube points (think this is silicone based??). Need to wait till shops are open.

 

I have some 'Servisiol Silicone Grease' but this link says usage only down to -5 degrees celcius: http://www.maplin.co.uk/p/servisol-multi-purpose-silicone-grease-50g-tube-re90x

 

Out of the garage years and years old before my dad died some 'MolySlip', molybdenum disulphide multi-porpose grease.

 

Looks like it's staying on the jack-stands over night!

 

I know to most it would look like I'm worrying about all this far too much but that's the type of person I am unfortunately.

Edited 17 July, 201610 yr by cosaw

Update:

 

So I phoned a VW branch this morning and as I thought there is a specific product that they use.  For the customer it's £51 inc. vat for 100g - yes you heard me right!  When I enquired he said that they have to use that grease and no I couldn't 'cadge a bit off them'!  So I said that basically we should make sure not to use a petroleum based product - to which he said: ' that is what we advise', but he said something silicone based is what to go for - when I asked.  He couldn't comment further than that and so couldn't recommend 'Red Rubber Grease' either way.

 

So I'm still stuck!

http://www.eurocarparts.com/ecp/p/car-accessories/car-maintenance-accessories/maintenance-fluids-and-greases/grease/?526770250&0&cc5_150

 

pagid ceratec and forget about it 

Many thanks for the suggestion steveo3002.  Done a bit of a search and can't find much info on this stuff as to whether it's safe on rubber and plastics or what it's made of.  You can be sure I will forget about it once I've reassembled everything but I wanna make sure I get the right stuff in there first.

 

I'm not ruling your suggestion out I just gonna try and find out a bit more on it first.  Also I've got to see how far it is on my push-bike to Eurocarparts!

 

Any suggestions from others?

you dont need to put it on rubber , its not some high tech space shuttle , carefull dab of whatever will be fine and just what any other garage would use 

Yes, I tend to overthink things and be a bit OCD.  The rubber I'm thinking it may get on is the dust seals on the piston ends of the cylinder.  The glide pieces that the shoes glide on are plastic.  Those are my concerns.

 

Think I better get on my bike to Eurocarparts to check this Ceratec out.

Edited 18 July, 201610 yr by cosaw

it simply shouldnt be pasted onto the rubbers , people have been using copper slip for decades and no problems 

 

dont overthink it , its just a normal car with normal drum brakes 

Cheers steveo - I will get off to Eurocarparts!

Next update and next most relevant question.  I've got one side totally reassembled and bled and am gonna check for leaks in the morning.  So the question: What is the correct way to adjust the wedge key?  Now that everything is lubed up and new will it self adjust once the foot-brake and hand-brake have been operated a few times - or will I have to manually pull it down through one of the holes on the drum/hub?  I've had no success yet with manually pulling the wedge key down on my dry runs.

it should self adjust after driving ...i find racing backwards and braking hard sets them nicely 

 

you didnt grease the adjuster did you?

I put some anti-seize/copper grease around the wedge key and the parts on the crossbar where the shoes fit into it.  Have I made a big mistake?

 

I'll update with progress pictures shortly.

 

Applied the Ceratec to the "Glide Pieces".  Off the yellow colour I'd think there was petroleum in it.

 

Before bleeding.

 

Edited 20 July, 201610 yr by cosaw

i dont put grease on the actual wedge , as the dust will stick to it and turn to hard sludge then stop it working

 

btw...once youve driven it if the handbrake seems poor , use something pointed through a bolt hole to pull the wedge down a little more , so that its starting to bind on one click , they dont always self adjust that great 

Many thanks for the details. You said: 'they don't always self adjust that great' - yes that is what I've found while messing with the old ones.  I've also found that the old ones were all grimed up and not working great - like you suggest.  Will just have to see how the anti-seize goes on, by the name it should do the job.  Hopefully if I have to pull the wedge key down manually  it will be easier now everything is in brand new condition.

OK.  Next bit of help required! SMALL PART NEEDED!

 

I've got the drum off on the nearside and the rubber bung that fits the inspection hole (to view the brake shoe thickness) is missing.  I'm guessing I'm gonna be dealing with a lot more corrosion on that side as weather will have been getting in.  Anyway phoned a VW branch and they say it's been "dropped without replacement" and to go to a motor factors or a breakers.

 

I'm gonna have a look on ebay this minute but if anyone can help me out that would be appreciated.  Don't fancy tarting that side up and then waiting on a bung while the rain gets back in!

 

What's the advice on driving the car with new brakes on one side and old on the other?

You can get a blanking rubber grommet from Halfrauds.

 

Not recommended to drive with un-balanced ( new/old) rear brakes

Cheers Nige! Pretty much knew it wasn't a good idea to drive but thought I'd ask anyway.  I drove about 500 yards just to check I actually had brakes!

 

Have to get on a bus to Halfords Mansfield then as they're a big branch.  Just been drinking out of the top of a cycle water bottle and the rubber stopper is a bit bigger but I think I might be able to do something with it until I get what I'm after!

 

Just had a look - hole is about 11mm so the 13 out of these will probably do: http://www.halfords.com/workshop-tools/garage-equipment/fuses-electricals-fixings/halfords-blanking-grommets-9-13mm

 

Probably crack on with disassembly then as I can't go anywhere!

Edited 20 July, 201610 yr by cosaw
More information.

I bought a box of various sized rubber bungs from Halfrauds some time ago