Reaching braking point

In the past 18 months, I’ve rebuilt the Mini’s front brakes, a Range Rover’s rear brakes, tried to fix a sticky caliper on a Saab 9000 and pretty much completely overhauled the Ford Maverick’s stoppers. I was hoping I could take a break from brakes, but live isn’t always fair.

The problem now is the BX. One front caliper is suffering from a sticky piston, while the other suffers from a sticky handbrake cable (handbrake is on the front wheels). The two are combining beautifully to create binding brakes. Just like we had on the Mini, Range Rover, Saab and Ford. What is it with bloomin’ brakes?!

BX brake disc

First look at the BX's brakes while recommissioning. They worked fine a few months ago! This one now suffers a sticky handbrake cable

My mood isn’t enhanced – though it probably should be – by the 2CV just sitting there looking smug. In almost 100,000 miles of motoring, and 12 years of ownership, the 2Cv has needed one set of front discs, a couple of sets of pads, a pair of new rear shoes and that’s about it. No binding issues at all, thanks apparently to the use of alloy pistons.

The problem with the others? Steel pistons. What a rubbish idea! Being steel, they inevitably corrode and then seize. The other issue is that the brakes on these cars all sit in the wheels, so get covered in road muck. The 2CV wears its front brakes on the sides of the gearbox, in the engine bay, and further away from wheel-hurled muck. Whoever was in charge of 2CV brakes deserves a medal. Especially as they’re so powerful as well!

I’ve now got the decision with the BX about whether to rebuild the front caliper or just buy a replacement (as I did on the Maverick). £40 for a complete caliper, but not sure how much a rebuild kit would be. Probably a fair bit as the piston is gunked up enough to need replacing. Hopefully pay day will allow me the luxury of the expensive option! In the meantime, yet another hero on the BX forum is sending me another handbrake cable, so I can sure that issue pretty easily.

I hope that this will bring an end to brake-fettling for some considerable time. I can dream can’t I?

Project Budget 4×4: Budget gets stretched

Brake work on the Maverick continues, but all is not well. After the horrors of finding one front brake pad worn down to the metal, the overhaul has revealed further issues.

Ford Maverick tinkering

Yet more brake trauma. It should be great after all of this work! (axle stand more secure than it looks...)

The first step was to pull apart the offside brake – the one with the faulty caliper. During this work, it quickly became apparent that the slide pins that the caliper moves on were totally seized up. This is what caused extreme wear on one pad – the seized caliper pistons just exaggerated the problem. The advice on the Nissan 4×4 Owners Club forum was to remove the entire caliper assembly, so it can be worked on away from the vehicle. If I had a big vice, this would have worked nicely, but I only have a battered Black & Decker workmate, which wouldn’t really help.

The caliper itself is a unit that holds the pads. There are two caliper pots on one side which act directly on one brake pad. The pressure then pulls the whole caliper towards the inside of the car, which thereby acts upon the opposite brake pad. Presumably this is an economic measure as most 4x4s would have four caliper pots per front brake, rather than the two used here. I consider it a fairly flakey idea as it just allows something else to go wrong – the sliders in this case which prevented the caliper from moving correctly.

So, the caliper was quickly lifted out of the way. The next challenge was to remove the slider pins from the caliper carrier. Brute force was necessary, all the while bearing in mind that there’s a good chance of snapping the pins if you get carried away. The pins have a 17mm nut at the end, which initially made me think they had to be unscrewed. No. This is merely to allow you tighten up the 13mm headed bolts that hold the caliper to the carrier.

I used a lot of penetrating oil, and one pin responded well to a chisel and a hammer – eventually coming free. The top one was very, very stuck though. I tried waggling it back and forth with a spanner, then tried the chisel and hammer approach, all the while soaking it in penetrating oil. After a very lengthy battle, it finally came out. No wonder the caliper wasn’t working! On the passenger side, the pins moved beautifully under no more than light finger pressure.

Then I could remove the caliper carrier and then the hub and brake disc. This isn’t too tricky, though there are lots of bits to keep an eye on and remember where they live. The auto-locking hub has to come off (an ideal opportunity to lubricate), then a circlip and some washers, followed by the outer wheel bearing and finally the disc/hub.

Separating the disc and hub proved very tricky, on both sides. For a start, the 14mm headed bolts were a pain to undo. If I’d remembered the instructions I’d seen online, I would have undone these bolts while the brakes were still fitted. As it was, I had to use a bar to prevent the hub from turning. Then the hub and disc seemed almost welded together with rust and friction. It took another serious bout of hammer-and-chisel work to separate the two parts.

Then it was quite easy to fit the hubs to the new discs and re-assemble. A good opportunity to repack the bearings with grease.

Sadly, I ran into problems locating new sliding pins, so work drew to a halt. I thought I’d try reassembling the nearside caliper, but then realised that the pistons were seized here too! Annoyingly, I’d already ordered a new caliper for the offside, so missed an opportunity to combine postage. The calipers cost £67 each delivered. I did consider rebuilding the calipers, but I’ve done it before and it’s not much fun. The parts were proving almost as expensive as a remanufactured caliper anyway, so the bullet was bitten. That means that total expenditure is now past my original £800 desire. I am left hoping that future months will be much cheaper!

And that’s where the project remains for the moment. I’m awaiting parts and just to make life even more interesting, I strained my back badly while clearing up. I hope to recover in time to get the brakes completed this week…

Mini caliper rebuild – Part 2

Having received the new wheel stud, I could complete the left-hand side. It all went back together beautifully and with an attractive assistant (the wife) on pedal duty, it was soon bled and functioning correctly. Lovely.

New brake caliper and disc fitted to proper Mini

Hmmm. Sooo shiny. seems a shame to cover it up with a wheel. New disc and pads plus refurbished caliper

Now attention could turn to the opposite side. I lowered the car back to the ground as I needed to reposition it – space is tight in the garage. This time,  I remembered to undo the main driveshaft nut BEFORE jacking the car up. Having read the Haynes manual, I decided to remove the caliper complete with pads this time. That was stupid – I then couldn’t get the pistons out. So, I connected the caliper back up and with the handy assistant again, could use hydraulic pressure to force the pistons most of the way out – using a spanner to stop the first one from popping all the way out until the second one was also easing outwards. It was then an easy job to use pliers to pull the pistons out – you wouldn’t want to do this if you were planning to re-use the pistons, but I wasn’t. They were in a dreadful state.

The only seized bolt on the entire job caused some issues – I couldn’t get the caliper into its two main parts. Eventually, I managed to smash a slightly-too-small socket onto the corroded head, and out it came. There may have been some colourful language before this! I then had to locate another bolt, which involved a trip to see a Mini enthusiast in Aberystwyth. Thanks Dave!

This was the side that had seized the most ferociously, and getting the old seals out proved a real ‘bind.’ See what I did there? The new seal holder things are incredibly soft and easy to damage but on this caliper, I actually managed to get one of the new ones to fit – though had to resort to an old one for the second piston. Then it was a simple case of swapping the disc and then re-fitting the caliper. New pads completed the job and with another bleeding session, she was ready to go!

The difference on the road was marked. When you’ve only got 45bhp to play with, binding brakes can be a very noticeable drag. I’m still to bed the brakes in – only 8 miles covered so far – but look forward to seeing how they go.

Very rusty brake disc

Yup, that'll be scrap then. No point putting this back on.

Betsy the 'proper' Mini

With fixed brakes, Betsy the Mini is ready to go!

Mini caliper rebuild – Part 1

Austin-Rover Mini City E

Mini gets a brake overhaul. Citroen BX rear seat should be back in the car, rather than being a Mini hat...

It was going so well. Despite a hectic week with much writing work, I actually managed to find some time to work on the Mini’s brakes. They’d started binding really badly and before Christmas, I had the pads out and discovered seriously manky pistons (see below). Rebuild time.

Rimmer Brothers were able to supply the bits I needed and after finally getting my hands on the necessary tools (Ebay saved me a fortune) I could begin work. Being a bloke, I decided to find my own way, rather than lower myself to reading instructions. This was how I ended up removing the caliper BEFORE undoing the main driveshaft nut. That made removing the brake disc (I decided to replace everything) impossible. Fortunately, I managed to put the wheel back on, jam a ramp underneath and then undo the driveshaft nut without having to go through the rigmarole of lowering the car of its axle stands.

When putting the wheel on, I noticed that I’d managed to damage one of the wheel stud threads, so work has come to a stop while I await a new one. I did get as far as fitting new pistons and seals to the caliper on that side though, so progress has been made! Once I get the new stud, I can put it all back together again and do the other side…

Corroded Mini brake piston

No wonder the brakes were binding - and this is the better side!