Rear caliper seized again!

[Dezzy]

Snap, the rubber washer type seal i could not see until i scraped all the rusty crud off.

A rubber boot like your drawing would have been a good idea.
I think knowing that they will end up seized at some point, it is an area that needs maintenance. Keep packed with copper grease around that pin. I'm sure a glove or similar would help

[Goran]

I'll give it a go, don't want the brand new calipers to be ruined too quickly. I have some silicone sealant somewhere I wonder how well it will stick to cast aluminium.

[Architex_mA8tey]

Could a track rod end gaitor like these be used to protect that area do you reckon?

[Dezzy]

Originally Posted by Goran

I'll give it a go, don't want the brand new calipers to be ruined too quickly. I have some silicone sealant somewhere I wonder how well it will stick to cast aluminium.

If you're going to use a glove make sure it's a nitrile, otherwise the oil / grease will react with the rubber. Not sure how long the silicon will last. It's an awkward shape to cover isn't it. Maybe some cable ties in the right places will zip the glove / cover down to the caliper body? If you were to cut the top of a finger off would the quadrant pop up through it so you could reattach the cable.

If you're not careful it'll look like your 8 has udders

Originally Posted by Architex_mA8tey

Could a track rod end gaitor like these be used to protect that area do you reckon?

Something like that Neil yes, but i'm thinking you'd probably have cover the whole area with something and put a slit in it to allow the quadrant to pop through, or a smaller boot. The gap between the quadrant and the caliper body is tight when it is back into position. In that photo above i had pried the quadrant out to scrape the crud off, this is how it looks when back in.

and is why i just threw a load of grease in the gap.

But were nearly there and obviously put in more thought than the original design. Anyone want to go into long life brake caliper design? Pull the udder one.

[ainarssems]

I had them get seized on C4 A6 and on D2 on one side but I think for me it was right side both times. The shaft for hanbrake gets rusty and the spring does not have enough force to return it.First I though spring was too week and bought new but that did not help much. then I took it apart but one of internal springs went flying never to be found so bought a refurbed unit for A6. At least when the time came on D2 I already knew what the issue was and how they are built so was able to take it apart without loosing any parts. Cleaned apart, reassembled and it has been fine for 6 or so years now. Other side was slightly stiff as well but not too bad. Since then I have been spraying ACF-50 anticorosion grease( http://www.ebay.co.uk/itm/ACF50-Anti...item2ee3b7afb5) on them when I get near them and even the one that was slightly stiff is moving freely now. C5 A6 did not have that issue but I have been spraying ACF-50 on it since we bought the car and it has not seized up.

[Goran]

Dezzy you're right it does look really funny with the glove on there. I should have inflated it so it looks like an udder

The glove fits almost perfectly with thumb going over the eyelet post, and the 3rd finger going over the handbrake lever. The plan was to smother silicone sealant around the glove openings and zip-tie the big opening after application of sealant.
I have these thin nitrile gloves but I think they wont last, too thin. I need some thicker gloves. Also my mechanic is going to think I'm bonkers if I hand them over to him like this

So considering the calipers are only £95 each and last roughly 10years, I'm trying a less promising approach, just to see what happens. I sprayed both calipers with ACF-50 into the pivot hole. On one caliper I smeared high-temp silicone sealant as a makeshift seal/washer around the opening. I don't think this is going to last but lets see.
On the second caliper I'm going to try to find a nitrile washer that will fit and see how long that lasts and if it keeps dirt out.

Also I wish I had time to get the calipers painted.

[Goran]

I managed to slip a 4mm rubber washer onto the lever pivot of the other caliper. The spring has to come off first. There is one place where you really have to squash the washer to get it through a 2mm gap but it seems to have survived. I packed some anti-corrosion grease in there too.

Unfortunately I had no time to order a proper nitrile washer, I cut a makeshift washer from a spare piece of SAI rubber tubing. A bit ghetto I know, lets see how long it lasts.

I hope I'm not doing more harm than good with these makeshift seals, if all I do is help trap moisture in there that might be worse than doing nothing?

Apologies for blurry picture.