One of the ongoing bugbears with the Daihatsu is the slight warping of the drivers side caliper carrier. With it all fitted it works OK, but getting the top slider bolt out for greasing/tinkering is a difficult task - it'll unwind on the threads, but once its fully unwound its a real challenge to remove. On the passenger side, it just pulls out easily with finger pressure, but the drivers side requires levering out with an open-ended spanner which is not how its intended to work. Getting it back in is a bit of a faff too, so its been at the back of my mind for a while now about getting hold of a replacement. Toyota sell them, but only as a complete unit with the caliper and bolts for a cool £470 + VAT which is too salty for me, so I've been trying to get one from a breaker. Luckily, both sides are interchangeable, unluckily, there aren't as many of these cars about as there once was so breakers aren't exactly abundant. 

The front calipers are shared throughout the whole range, from the lowly 989cc with 59bhp all the way up to the mental 713cc 4WD 118bhp monster. My car sits at second place in the performance tree, with 110bhp on tap and the braking is a bit marginal frankly! What this meant though was that theoretically any carrier from any M100/M101 Sirion would work. I spotted a guy breaking a 989cc car on facebook the week before last and messaged to enquire about the carrier, asking if he'd sell me one or both, he replied in the positive and electric money changed hands. A couple of days later, a parcel arrived

The guy had sent me some pics, and advised the carriers were a bit corroded, he wasn't kidding. I opened up the unexpectedly heavy parcel to be greeted with these lumps of rust

Erk. Thats pretty grotty. However, in addition to being grotty, it was two sets of pads, complete calipers and carriers, not JUST the carriers I was expecting, so there is some bonus content here which is good. However, these are is a bad way. I tried to see if they were totally seized. One actually moved really well, vomiting out some ancient brake fluid from the cut-off flexi when I pressed the piston back in. The other was a bit more stubborn, but I don't think its toast. Anyway, thats not the important bit! I clamped the calipers in my bench vice and hammered on a 14mm socket to the slider bolts, which had pretty badly corroded heads and heaved on a ratchet and amazingly all 4 came out without a fuss. The sliders hadn't seen much lubrication so were a bit difficult to extract, but even dry, came out easier than a well-greased slider from my carrier. With the carriers off, I could have a closer look

Thats pretty grim. Less grim than the calipers themselves, but pretty grim nonetheless. I put them into my bench vice and gave them a good scrub with a wire brush

Which took some rust off, but wasn't touching some of the really encrusted stuff. I put them both on the bench to see how we were doing

In anticipation of needing to do some derusting I had bought myself some citric acid crystals, so it was time for some CHEMISTRY. I put 100g of citric acid crystals and 2 litres of boiling water in a bucket and them dropped the two carriers, the carrier > hub bolts and the slider bolts in for a bath

It started fizzing quite alarmingly, I gave it all a stir up and left it for 30 mins or so, then lifted the carriers out - without gloves because I'm an idiot, and now know EXACTLY where all the cuts on my hands are now - and scrubbed them with an old toothbrush to agitate the surface rust. This was after about an hour and two soaks/scrubs

I repeated this at ~30 minute intervals for about 4 hours when the bubbling was much slower, as the acid solution would have been loads cooler, and had mostly reacted by this point so out it all came

As you can see, there now a lot of clean metal, but plenty of rusty crud stuck on. The parts were still covered with acidy solution, so next up was another bath, this time in hot water and soda crystals to neutralise the acid

I rapidly vacated the kitchen before my long-suffering wife saw what I was doing! After about 20 minutes I removed the calipers and bolts from the alkaline solution and washed them in clean hot water. This was the result

now THAT is a lot better. Next up was to clean up the bores that the slider bolts fit into. I used my dremel with a mini felt polishing cylinder and some autosol polish to clean them up to a nice shiny surface finish, then  used a cotton earbud to clean the polish reside out with meths. After this, I left the carrier on the radiator in the house overnight to dry out thoroughly. The next morning I set to with the dremel and a drill, using brass wire wheels to take as much of the encrusted rusty off as I could

I'm not displeased with that! About 90% of the rust is gone, especially from the flanged buts round the bores that the sliders go into (which helps locate the tiny rubber boots) and the square cutouts that the pads fit into. The threaded holes had the threads cleaned up and lightly lubricated with some GT85 spray.

I removed the front drivers side wheel, and removed the caliper and carrier (struggling with the top slider as usual) and then fitted up the regreased sliders to the carrier on the bench before fitting it carefully to the hub on the car. The slider bolts were reused, because they're only about 6 months old and have been barely used. They got re-greased and I'll check it all carefully after a few miles. It all gone done up and the wheel refitted, but I couldn't take it out to play because it was boxed into the garage by one of the other cars so hopefully I'll take it for a run tomorrow.

I think the remaining rusty mess might be beyond saving but I have a sneaky plan involving a pair of brand new calipers and returning two lumps of solid ferrous oxide for a rebate, but that will have to wait for a little while!