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Old 22nd September 2019, 18:18   #101
David Lawrence
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Quote:
Originally Posted by Jules View Post
Remember 99% of garages don't have a T4 so think how many operations are done without!!

Now this will shock the motor industry :

The bicycle industry bleed their hydraulic systems from slave end & we've done the same with our electric bicycles !

It works fantastically and much quicker.
If you think about it air bubbles naturally want to rise, so inserting fluid from the lowest point makes perfect sense.

Firstly though give a few pumps in traditional manner to drain the dirty fluid from each slave so as not to be pumping contaminated fluid back up the system into the master.

Works great we've done it on our own cars and have solid pedals.

You have to have 2 syringes, one for inserting fluid at slave and another for extracting fluid at the master so it doesn't overflow.

Enjoy watching the air bubbles end up at top of the master where they should be
I can confirm Jules has cured my problematic front left and restored normal braking after I tried traditional methods 10 times or more and failed.
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Old 23rd September 2019, 11:16   #102
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I've just come across this topic. I hadn't heard of it being an issue but then I haven't owned a 75 before now.

Interesting though. Because I work in a Ford and Mazda main dealer and there are ABS related oddities on some of their models;

The modern Mazda's such as 2012/13 onwards Mazda 6 and the CX5 have sinking brake pedals when engine is running. I have carried out a routine brake fluid change/bleed and this makes no difference. The pedal sinks when engine running, but not when the engine is off - solid as a rock and no sinking when engine off.

The Fiesta 2008/9 ish onward shape can suffer with a very poor brake pedal travel/feel. The pedal can be pushed quite a way before braking occurs.
No amount of normal bleeding cures the problem. The solution is an 'IDS brake fluid bleed'. IDS= Fords diagnostic machine. This always cures it.
It does mean a brake fluid change on a Fiesta can cost £100 not £40.

Last edited by ashy90; 23rd September 2019 at 12:18..
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Old 24th September 2019, 01:00   #103
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I have a theory on this, air or old moisture rich fluid remaining in the ABS modulator is released at some point either through a purging cycle or activation. So the pedal softens slightly. The T4 operation flushes this out to avoid it.

I believe I noticed a slight difference last year after purposely activating the ABS on ice (straight line no traffic etc of course). I had, two months before, flushed and replaced brakes and fluid. I wouldnt even say it was softer, but there was a difference after, in saying that, I cannot deny any placebo effect either.

As a sinking pedal, all diesels I think will do this when stationary and idling as the vacuum builds. Still idling, pump it a few times, and it will solidify, then hold the pedal, and it will sink again as the vacuum rebuilds.

This was what caused my mothers sinking pedal!!! 'I thought it didn't slow down the way it used to'
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Old 24th September 2019, 01:17   #104
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nothing to see here

refreshing after the 2am site server shutdown reposted the same message
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Old 28th September 2019, 10:51   #105
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Quote:
Originally Posted by Jules View Post
Remember 99% of garages don't have a T4 so think how many operations are done without!!

Now this will shock the motor industry :

The bicycle industry bleed their hydraulic systems from slave end & we've done the same with our electric bicycles !

It works fantastically and much quicker.
If you think about it air bubbles naturally want to rise, so inserting fluid from the lowest point makes perfect sense.

Firstly though give a few pumps in traditional manner to drain the dirty fluid from each slave so as not to be pumping contaminated fluid back up the system into the master.

Works great we've done it on our own cars and have solid pedals.

You have to have 2 syringes, one for inserting fluid at slave and another for extracting fluid at the master so it doesn't overflow.

Enjoy watching the air bubbles end up at top of the master where they should be


I'm going to need to drain the brake fluid out of the system in order to change over the modulator.

Am I understanding this correctly that filling the system via the bleed valve on each caliper is the method to fill both circuits in the ABS modulator? Is this not travelling the wrong way through the master cylinder? Apologies for my ignorance.
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Old 28th September 2019, 14:15   #106
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Originally Posted by Typhoon190 View Post
I'm going to need to drain the brake fluid out of the system in order to change over the modulator.

Am I understanding this correctly that filling the system via the bleed valve on each caliper is the method to fill both circuits in the ABS modulator? Is this not travelling the wrong way through the master cylinder? Apologies for my ignorance.
YES, the wrong way.

However when using this method the master cylinder is OPEN circuit and the fluid will return to the reservoir which will need to be monitored and the excess fluid drained off.
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Old 28th September 2019, 16:39   #107
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YES, the wrong way.

However when using this method the master cylinder is OPEN circuit and the fluid will return to the reservoir which will need to be monitored and the excess fluid drained off.
I was under the impression that putting fluid through the master cylinder 'the wrong' way could flip the seals if too much pressure was behind it. I've always taken care moving the caliper pistons back when replacing pads, as the 'proper' way is to allow the fluid out of the the bleed valve I thought?

Does ignition on make the ABS modulator open circuit, or does the engine need to be running? Thanks.
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Old 28th September 2019, 23:29   #108
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It makes no difference which way you do it.

We used to refill the conventional way but lately we fill from bleed nipples, as it's quicker to remove all air bubbles.

We have a T4 but never had to use it to bleed the system or the modulator.
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Old 29th September 2019, 10:22   #109
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Originally Posted by Jules View Post
I use my Sealy sump pump regularly to bleed brakes and clutches never had a problem!!
Sucking it out from the bleed nipple end gets all the air out in one go WITHOUT pressing any pedals. One man job too.
Do you still use the Sealey pump Jules? (post 47)

Is it the VS820? https://www.amazon.co.uk/Sealey-VS82...c=1&th=1&psc=1
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Old 29th September 2019, 10:45   #110
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Originally Posted by Typhoon190 View Post
I was under the impression that putting fluid through the master cylinder 'the wrong' way could flip the seals if too much pressure was behind it. I've always taken care moving the caliper pistons back when replacing pads, as the 'proper' way is to allow the fluid out of the the bleed valve I thought?

Does ignition on make the ABS modulator open circuit, or does the engine need to be running? Thanks.
If the folk that keep this old wives tale alive thought about it would they think the seals would flip if you braked hard !!!!

As I said in the previous post the circuit through the master cylinder is OPEN CIRCUIT at rest. The piston moves back PAST the filler hole from the reservoir. This is how the fluid in the master cylinder is automatically topped up.

This through-hole is closed off as the piston moves forward under braking.---
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