I need a new set of disks and pads on the Ka, which I know how to swap, but I've not bled brakes before. Do I need a special spanner to get a bleed nipple open or is it a standard size? Am I fine pushing the piston back myself or do I really need a windback tool? I'm considering putting DOT 5.1 rather than DOT 4 in, how much better is it? The brakes on my car tend to get very hot on occasion.
40 minutes gone and Dervman hasn't replied......he's slipping....
You don't normally have to bleed brakes after doing a pad/disc change.
Standard, but use a ring spanner or socket to loosen them.
Not sure about the Ka, but on most you can make do without a special tool. A G clamp or even valve spring compressor can be as good.
It's probably a good idea to change the fluid anyway if you're not certain when it was last done - the recommendation is every two years or so. Brake fluids to DOT spec are all reverse compatible, so using the latest should be fine.
It may be worth mentioning the honourable exception, DOT 5. (not 5.1).
cheers, clive
Hence me asking about bleeding. I was going to put Green stuffs and DOT 5.1 in. And then I thought bugger it, and decided to get boggo pads and DOT 4 and spend the rest of my money on my mountain bike. The fluid's not very old but it has had a bloody good roasting, so it's not going to be up to scratch.
In theory, the silicone stuff should mix too. Not that I'd try it.
hmm, i'd double check that, i was changing all the fluid on my alfa the other day, was going to put 5.1 in as it's "better" but didn't in the end for 2 reasons, firstly on the bottle it said dont mix with non 5.1 fluids, so it might have caused problems if there was any 4 left in there, and on the brake reservoir on the car it says "use dot 4 only" , as it did in the "manual" thing they have in the shops telling you which fluid to use
Best to use a full hex socket to crack them open, it reduces the possiblity of rounding them off.
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It would say that, because if you mix it with a lower spec fluid, it will no longer meet *its* spec.
Well, they've no way of knowing if there is going to be a better spec. I'd read it as 'use dot 4 or better'.
I was reading an old Rover manual the other day - it said 'use only Lodge spark plugs'. ;-)
Nope, I don't think so - I've heard many people say they are completely different.
(any pointers to somebody saying they are compatible?)
cheers, clive
It's not normal to bleed brakes when replacing disks and pads. If you want to, a standard spanner, a short length of hose of the right diameter and a container of oil to stick the end in, is all you need. After new pads have been fitted there is always some play in the brake pedal. This is not air but just the movement necessary to get the pads back in contact with the disk. A few pumps of the pedal sorts this out.
I've never used a windback tool. Firm pressure on some form of lever (like a socket set extension) has done the job for me. The pistons move slowly back so don't be tempted to hammer anything. Take care too not to damage the rubber seals.
Brakes are meant to get hot. They convert the kinetic energy (movement) into heat energy. Unless you experience the break oil overheating (bubbles form and the brakes suddenly go all spongy - very nasty as it happens when you are pushing the car hard) stick to what is specified for the Ka.
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I've had the pads smoke on several occasions, but never had the pedal suddenly go completely soft, just a gradual softening.
very hydroscopic you will need to change it every 2 months as opposed to every 2 years :)
everyone has covered most things, so I'll just chip in my tuppence worth :) you say you've given your brakes a bit of a roasting? hot fluid boils (ever thought of the boiling point of brake fluid and why it's mentioned?) this leads to air in the system. not a lot, but maybe enough to cause a small delay in you pressing the pedal and something happening
most bleed nipples are11 or 12mm (or 7/16ths if you are working in old money) use a full 6 sided spanner to crack them open, they won't break, but make sure you undo them the right way ;)
the bleeding process has been mentioned before but if you want to flush new fluid through then just keep topping the level up till "clean" fluid comes out
your brakes will feel better with fresh stuff in them, but you might not notice until you start to hammer them
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