Skoda Octavia 2002 rear brake troubles

[Mooseketeer]

Hello all,

 

My first post here and I hope I can find some help. So, I did something silly and decided to "troubleshoot" some problems I was having (or thought I was having) with the rear passenger brake. I felt like the brake was "sticking" or not functioning properly, and after driving I could smell burning/brake fluid. This is on a 2002 skoda octavia. My first skoda experience.

 

So, with little mechanical experience I decided to pop off the tire and take a look at the drum brakes. Took some finessing but I was able to pop off the drum and the brakes initially looked like the first picture. I had my girlfriend sit in the car and pull the emergency brake so I could see whats going on inside the drum brakes... but then she pressed the brake pedal in without the drum on. So the piston popped out and leaked some fluid. I assembled the piston again with the spring that popped out.

 

I'm just trying to get the drum back, but it seems to be getting stuck on one of the shoes maybe? No amount of work can get the drum to snuggle up to the backing plate. See picture 1 for the initial state when I pulled the drum off, and picture 2 for the current state where I cant get the drum back on....

 

Anyone have any thoughts on how to get this all back together so I can drive it over to the mechanic and admit my defeat? Also, with the piston popping out like that, should I be worried about significant damages to the system?

 

Many thanks...

 

before:

 

after:

[group1rs]

In the bottom pic which is clearer the adjustment mechanism needs to be pushed up. This is the vertical wedge to the right of hub in pic. It has a soft spring attached. As the shoes wear the spring pulls the wedge down thus expanding shoes to meet inside of drum surface. Your girlfriend by pressing the foot brake without drum fitted has expanded the shoes to the maximum limit. Simply lever wedge back up to the top and shoes will be retracted. You may also have a lip on the drums that can make them difficult to refit. But you will never get drums back on with wedge in position shown. Piston popping out will require brakes to be bled as you will now have air in system. But as long as piston was cleaned before re assembly all will be ok once brakes are bled. Also you need to get some brake cleaner and clean all the rusty dust out.Hope this helps.

[CRB]

If you have been unlucky, there may be fluid on the right-hand shoe.

 

I do not know if cleaner would be enough to ensure all traces of fluid were eradicated. On the LT, I just replaced the set when the actuator leaked all over the innards.

 

As mentioned by group1rs, there is probably a lip on the drum which makes it difficult to get the drum back on without squeezing the shoes together a bit.

 

Do not use compressed air to clean the dust out, it is not made to be inhaled.

[Mooseketeer]

Ok.. so I push up the vertical metal bar with the spring hooked up to it.. on the right side, and this should squeeze the shoes together. I can try that. 

 

In the meantime, is it ok to top off the brake fluid and drive it to the shop where they can bleed it? Should be safe enough I think...

[CRB]

The air is at the furthest point of the system, though it would make its' way very slowly upwards. Topping up probably will not do much to help, since if you have lost sufficient to uncover the fluid entries to the other, front LH/RH and other rear actuator, you will be locking air into them too.

 

A bit pessimistic, but you will find that the brakes will not be the same even after you top up.

[group1rs]

Brakes will be dangerous now you have air in the system. Don't drive until bled properly. Re assemble and if you can't bleed them yourself get it recovered to a qualified mechanic.

[Mooseketeer]

Yes, I understand they will need to be bled for it to be safe. As long as I can get it to the mechanic...

 

Anyways, still wrestling trying to get the drum back on. I've levered the "wedge" up and the drum gets on to a certain point before its getting stuck.. Pictures show the current state of the shoes and the little bit of space left when I try to get the drum back on... Am I just at a point where I need to line up the holes as best as possible and screw it all back together? Is this rust causing the issue not allowing the drum to seat flush with the backplate? It feels like there is something in the brake assembly in the upper right quadrant pushing on the drum.

[group1rs]

It all looks in a bit of a mess to be honest. It matters not if your mechanic is 2 meters away or 200 miles it's an accident waiting to happen. Seeing as brakes are what stop you from hitting something I would suggest a complete overhaul ! And don't drive it until safely fixed.

[Mooseketeer]

I have no problem getting a complete overhaul of the brake. Would be nice to get the damn drum back on and get over to a shop to get it all sorted though... if only I could get that drum back on. 

[group1rs]

Shoe has probably become dislodged now causing drum not to go back on.

[Mooseketeer]

It all seems to be hanging in place. It's a bit concerning that the right side of the piston seems to not be sticking in there very securely... but what is the best bet to just get this thing together and down the road to the mechanic, avoiding putting it on a flatbed tow... I don't even want to think about what it costs to tow a car where I am living...

[Mooseketeer]

Also, to clarify, this is the wedge that needs to be levered up in the direction of the arrow in the picture? Seems like it moves quite easily up, stretching the spring, but little movement in the shoe.

[group1rs]

Yep that's the wedge adjuster. Once pushed up shoes should retract. From your pic the R/H shoe is not retracting. It should push the piston back into the wheel cylinder much more.

[Mooseketeer]

I got it all back together. I think the issue is a busted wheel cylinder. I feel the piston on the righthand side of the image is busted. It seems to be too loose, or just sitting in there and the force of the spring could cause it to pop out unless there is some force pushing up against it. My guess is it needs to be replaced, amongst other issues. I hope once I get some fluid to top off the reservoir I can pump the brakes a few times to see if pressure builds up and then get it to a mechanic... the wheel is abnormally difficult to rotate, so there is still some issue with the brake seizing up against the wheel. Not sure why. 

[Mooseketeer]

So I've spent some time putting everything back together, trying to clean up things very roughly... I bled the brake lines and everything seems to be "working". No sinking pedal. The car stops just as well as before. But I know there are some issues with the brakes in the rear. I believe the cylinders (at least on one side) leak very slightly... or at least it looked like there was some mess inside the brake drum before I cleaned it up. Now that its relatively clean I'll drive around and peek at it later to see if it is new fluid coming out.

 

But I have two questions to you helpful forum members...

 

1) The right rear wheel cylinder is not aligned on the brake shoe. I can't really seem to easily reposition the brake shoe so it rests on the metal part of the piston. Is this something achieved by removing the brake shoes and reinstalling them? Or just a matter of loosening up some springs and adjusting into place? Alignment looks ok on the other side of the cylinder. Pictures 1 and 2 for reference.

 

 

 

2) I am not familiar enough with brake wear and tear, but what are some opinions on the state of the shoes and brake drums. The drums seem to have some grooves and there seems to be wear on the brake shoes from the irregularities on the drums... Pictures 3 and 4 for reference.

 

 

 

Thanks for the help again.

[kentphil1]

The brake shoe needs to be positioned on the wheel cylinder piston by removing the hold down spring (not the return spring) and carefully positioning the shoe on the cylinder using a pair of pliers.

 

At the moment, the way the photo shows the brakes at the moment, only one side of the cylinder will work as designed, as the other side is resting off the cylinder and may allow the piston to pop out under braking.

 

Looking at the photos, unless they are really exaggerating the wear, the shoes and drums appear to be near or even past their service limit due to the heavy grooving.

 

I certainly would not like to try an emergency stop with the shoe on the cylinder as it is now, as the results may be tears before bedtime

[Mooseketeer]

Ok, great. So just removing the hold down spring on the side that needs repositioning then? Not both springs?

Also, yes I will probably spend some free time soon to replace brakes and drums. I guess once the brake drums are grooves as such there is not much to do... Hopefully a shiny new drum will fit on the rusty backing plate ok...

[group1rs]

Yep as Kentphil1 says shoes should be central on piston. Something wrong there. They are a pain to do though I was swearing lots when I did my fabia ones a few weeks ago.

[kentphil1]

Ok, great. So just removing the hold down spring on the side that needs repositioning then? Not both springs?

Also, yes I will probably spend some free time soon to replace brakes and drums. I guess once the brake drums are grooves as such there is not much to do... Hopefully a shiny new drum will fit on the rusty backing plate ok...

I must admit I'm struggling to see how the rear brakes can have bled out properly if the shoe was not resting on both sides of the cylinder. I would suggest once you get the shoes fitted correctly that you rebleed the rear brakes to be certain you have expelled all air. How much air came out in the bleed bottle when you bled the brakes before?.

[Mooseketeer]

A bit of air initially because I'm guessing air got in when I had my first 'cylinder popping out' issue. Hard to measure the air though. But it was all fluid after I pumped and bled the brakes enough.

But I looked back on the original photos of the brake before I messed about and noticed the piston was not properly aligned on the brake. So it's likely been misaligned for a while before until I decided to look at the brakes for the first time last week. I guess I'll give a go to try and align them.

But my follow up question, I won't have to unclip any other springs except the spring holding down the brake shoe on the affected side? I'll try.

[kentphil1]

Basically no, as the more springs that you take off, you will struggle to get back on. You need to gently ease the shoe outwards in the direction it would move if the brake was pressed, whilst trying to position it back on the cylinder.

 

If you struggle to achieve this, you may have to release the bottom return spring to allow you to reposition the shoes that way.

 

I should add a really strong word of caution here about how capable you feel doing this as if you get it wrong and you end up in an accident at very least you will harm yourself and at worst someone else with you. You said in your first post that you had limited mechanical experience, and to be honest, messing with brakes this deeply is not the best way to learn.

 

It may be wiser to box it up, take it to a local indy and let him finish the last bit because if the self adjuster springs while you are trying to move the shoe and it over extends, then you will be left with the same amount of work to refit it all as if you were renewing the shoes. If you have not done this before it will be quite daunting for you to work out.

 

Just my point of view and the final say is all yours.

 

Phil.

[group1rs]

A small amount of knowledge becomes a dangerous thing ! It's not something that can be taken lightly get it wrong and could end in disaster.

[Mooseketeer]

It doesn't seem terribly complicated though. Fairly easy in theory if not maybe frustrating wrestling tension and rusty parts. It also seems like one should be able to tell if they fit everything correctly and then you can give it a test in the driveway. A few more controlled braking tests and peeking into the brakes to make sure everything is in order.

I appreciate the help. Seems like some say 'don't bother trying' and others say 'it's very straightforward and possible to do at home'. I'll probably give it a go and then if all else fails take it to the shop. Seems hard to imagine it failing though... With enough effort that is. I guess at some point it's everyone's first time, even the guy working at the brake shop...

[kentphil1]

The difference is that the guy on his first time at the brake shop has an experienced man working alongside him to guide him through and prevent errors. If you are going to do this , take loads of before photos and take your time. Be spotlessly clean in the way you leave the lining material, as dirty greasy fingerprints spell pain and doom.

 

If you are not sure of something, make a quick note that YOU can understand before you dismantle it, and ideally have a Haynes manual near, as whilst they are by far not perfect, they are much better than nothing.

 

And one last thing, to do this will mean the car will be in the air a while, so work safe and put an axle stand under the car. I've already pulled one neighbour out from under a Fiat Punto, when it fell off the jack and pinned him under the car, so spend the time and be safe mate.

[Mooseketeer]

Of course safety first, that's a given. And of course I've drawn up the diagrams and pictures to make sure I understand fully how the parts work together, and how to reassemble the whole system.

Of course still might mean I'll come here to ask for some tips! Anyways, I say I have limited mechanical experience in that I have worked much with older cars, but I'm not a foreigner to building things with my hands or having the engineering background. I'll give it a go and come back with my tears and frustrations!

Thanks for the tips though. Hopefully it goes smoothly.