topping up brake fluid

Shocks, springs, anything to do with the running gear

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Dan224
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topping up brake fluid

Post by Dan224 »

I was taught never to top up brake fluid, the reasoning is its an indication as to when to renew your pads, as the pads wear, the fluid level drops, and when the low fluid light comes on its time to change your pads. Is this idea actually right or is it just another myth that I've been suckered into?

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steve_earwig
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Re: topping up brake fluid

Post by steve_earwig »

On most cars I've ever had you'd be hearing the sound of metal on metal before the fluid warning light came on. I suppose it might have some basis in reality if all 8 pads wear at the same rate but they don't. It might give some indication of how the pads are wearing but no substitute for giving them a visual.

If the warning light came on I'd suspect a bigger issue than worn out pads too.

I'm also pretty certain that the amount it drops between new pads and worn out pads isn't enough to drop it below the minimum, so I never top brake fluid up - I hate dealing with the stuff anyway.

Thinking about it, I have never had a brake fluid light come on anyway.
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lozz
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Re: topping up brake fluid

Post by lozz »

You have to top them up By law, :( (CU10 offence 3 points plus fine)

ithink id sooner top the brake fluid up a few mms rather than Bin the pads.
Everycar ive had/worked on uptill now ive had to take fluid out when ive changed the pads,
leestudd30
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Re: topping up brake fluid

Post by leestudd30 »

How do you change the fluid anyway? Would I need to get under the car or is there any way I can just drain it from the reservoir under the bonnet myself?
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ColinCranwell
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Re: topping up brake fluid

Post by ColinCranwell »

Your original remark was half right.
If the light comes on, it means something is wrong. Generally, the amount the pads wear should not be enough to trigger the light, certainly not in older cars. So if the fluid level drops, then just topping it up doesn't solve the underlying problem.
If the fluid is in for several years it will decay and evaporate, so if the light comes on in this case it is telling you the fluid needs replaced. Otherwise you have a leak somewhere.

The point about changing the fluid is to get the old, worked oil out of the system. That is the stuff in the cylinders. So if you are going to change the oil, it needs to be pumped through, using the foot pedal and bled off at each cylinder.
Yes, you have to get your hands dirty.

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steve_earwig
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Re: topping up brake fluid

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Unskilled meddling sin©e 2007

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omega
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Re: topping up brake fluid

Post by omega »

well ive never had to change or top up my fluid because ive changed the pads and dont understand why you would need to.in fact if anything i would say the oppisite might be true eg you might need to remove some brake fluid.the reason for this is the same reason you should change your brake fluid every 2 years in that brake fluid absorbes water so in fact your fluid level could go up,but in the real world i think the amount of water would be miniscal.
the reason you are changing the pads is that they are worn or damaged now it is very unlikly that the person before you fitted old worn pads so they would have been new and the fluid level would have been correct.now as the brakeing system is a sealed system none is going to get out unless you have a leak.
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