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Spongey brakes

Now then... old brakes, how come they are always spongey and what's the cure.


Before anyone starts with the obvious (bleeding and new hoses) let me expand.

I've noticed in my old cars that the brakes can never be restored to "as new" sharp/hard pedal no matter how (or how much) you bleed them.

My 155 received new hoses all round (braided)... the pedal was "not bad" but still spongey.
My 145 I've bled to death and the pedal is "not bad" but still spongey.
My mate's Vauxhall Corsa donkey.. we bled that to death.. but still spongey.
Now, seester's Megane. Bled it to death and the pedal is still spongey.

Now I could be doing it wrong.. but I dunno think so. In each car, particularly the Renoort, the pedal feels pretty good until you start the engine. Then it goes a bit spongey.

The pedal doesn't ever collapse... just starts feeling firm until the engine's running.

What's the problem and how can I fix it. It must be related to the Servo in some way, isn't it?


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old brake systems get a bit more play in them: slider pins, caliper pistons, main brake cylinder aswell. Then there's the flexible brake lines (6 on the 155 and 145). And then the rust and other crap preventing the pads/shoes from sliding effortlessly.

Old fluid makes brakes feel spongey aswell.

When the brakes aren't assisted you're not likely to feel this, but it's another matter when there's vacuum.

Don't see how you're easily going to rectify all this on an older car.
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When the engines running you get the servo assistance kicking in . Like another leg helping you . That's why they feel softer. It's supposed to be like that.
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I hate brake bleeding too! Most recently i put new hoses all round and a new copper line and bled 5ltrs all kinds of ways- EeziMyArse bleed - buddy bleed - engine on/off - you name it!? , freed and greased all calipers and i still have a cr-ap pedal but she went through mot without issue,!? But its still pants and i know its pants. Ralf, on Alfas as i understand the only real way to cure it is with EXAMINER as i reckon you have trapped air in the abs pump?
I read that cars with abs, which is 90% of cars in daily use(dont quote me on this) are ALL a nightmare if you get air into their abs pumps.
....PPS. I still have spongy pedal but car is off road having new clutch. I will be going back to my local specialist and pushing him to link his examiner and ill take wheels off as he fobbed me off last time i visited.
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(Post Link) post #5 of 12 Old 11-11-14 Thread Starter
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Hmm.. yes... I'm just curious... because all old cars are like that... then when I get into a Hire care, the first few miles I'm pulling my face off the inside of the windscreen because the brake pedal is "hard" even right at the top of its travel.

I don't think it's the brakes condition, since on my 155 I pretty much changed or refurbished everything other than the m/c, ABS and servo. It had new sliding pins, lines, brake discs, pads and overhauled and/or re-engineered calipers... and then it felt more or less the same as the 145 which was just "bled".

The ABS could be a contender since the 155's brakes were all apart... (changed the pipes out of the ABS unit, so it would certainly have had air in it).... and the Examiner doodah makes sense, since "at the factory" they must bleed the brakes in just a few minutes... I guess that's what we need to re-create.

Does the Examiner doodah have a way to hold "open" a valve or something inside the ABS unit, to allow the fluid through?


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Hi Ralf, yes it does and the difference between Examiner & MES is that MES claims to be performing the abs valve opening procedire but it doesn't.

As regards the procedure the programme identifies left rear, right rear, left front & right front. You then click on which corner you need to bleed, run valve opening on Examiner (think it runs for upto 7 secs) and bleed. So, you run the programme as you bleed the line.
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Where can I get one of these Examiners from? Searching eBay only brings up a load of gynaeological equipment..

Or do I have to bring my car to the dealer and ask them to bleed the brakes..?

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You can buy units for approx 500 or pay your specialist. I reckon that if you offered to remove and refitt wheels he/she might just charge you for linking computer?
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When I've got Blue on the road (still fixing the top end) and MOT'd ... I'll see if I can get an Examinier equipped someone to bleed the brakes. I'm just curious what kind of improvement is possible, over just normal (on the driveway) bleeding. I'm just curious to know if there's "a way" to get a properly firm pedal, rather than a slightly baggy/normal old car pedal..

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If you do find one? Please tell!
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I battled spongy brakes and a poor pedal feel for a good few weeks earlier this year when trying to get my old 164 through its first MOT in 3 years. Firstly the rear brake compensator was frozen meaning limited braking effort was possible at the rear calipers, this condition was worsened by the valve freezing in a manner that created a non-symetrical effect on not just the rear caliper pistons but also diverted pressure unequally to the fronts. The situation was aggravated by both rear calipers having faulty self adjusters on the handbrake mech, I believe the frozen compensator reduced the amount of movement at the rear calipers and over time the lack of internal movement meant they stopped working, so as the brake pad became worn the self adjusters failed to keep the pads in close proximity to the brake disc. I bought reconditioned rear calipers, the nearside worked fine but the offside required 3 different attempts, I noticed that the caliper pistons would only protract partially before retracting a couple of mm after approx 2 to 3 minutes. Once I was satisfied I had working calipers I ended up bleeding a good 7litres of fluid but still had a spongy pedal as soon as the engine was running, the car would stop but was frankly rubbish. Eventually I took it to a trusted garage where over 3 days they repeatedly bled the brakes using a pressure bleeder. Lots of air was removed and the pedal feel was transformed, I took the car back a couple of days later and they repeated the bleeding and I was amazed how much air was still present, the result was a firm modulated pedal with absolutely no spongyness. Last couple of months have allowed the brakes to bed in and the brakes are now a strong point of the car. Parking brake works as well, which is novel!
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