Citroen C5 mk1 brake fluid leak after changing brake pads and discs

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deksa
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Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by deksa »

Hello,
I was changing my back side brake pads and reinstalling the back side repaired discs, which means I opened up both calipers in the back.
That process was done with the parking brake on (front brakes).
After doing this I have brake fluid leak under the front passenger side wheel.

Since I had only 1 car jack:
I removed the driver side back wheel, removed the old brake pads, opened the caliper, changed the disc, closed the caliper, installed the new brake pads (there was no need to push back the pistons since the old pads were actually new but squeaking). Then I put on the wheel and lowered down that side so I can go do the same process on the other side.
Now we are on the passenger side, done the same process, but here before I put the wheel down I opened the bleed valve so I could release the air from that side. After doing that I put back the wheel, and lowered down so I can get back on the first driver side to bleed the valve too.
Jacked up the drivers side, removed the wheel, bled out the air, reinstalled the wheel, lowered down the car which was ready to test.

(I was using the following bleed method: Opened the valve, another person was punching the pedal a couple of times until it hardens, then a constant push until there was a steady stream of fluid, then I close the valve while the pedal was pushed).

When I turned my car, slowly started to drive, pushed on the pedal and it went to the end without braking.
Maybe late but only then I remembered to check the fluid level under the hood (before starting anything this was full on normal) and now I realized that the canister was empty. Strange thing was I did not lose lots of fluid while doing these changes so when I checked the front side I saw a pool with brake fluid under the passenger front wheel. (just a reminder I never touched the front brakes, except my parking brake was on when I was changing and bleeding the back side).

I refiled the tank with Dot 4 brake fluid and again the pedal was dropping but the fluid level remained the same.

What now? Do I need to bleed the front valves too, all 4 valves on both sides? If so why? I have never touched the front ones? Why is there fluid loss?

Thanks!

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Hell Razor5543
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by Hell Razor5543 »

I would bleed all of the brakes. I cannot explain the fluid loss, but as you lost a lot it is possible there is air in the system, and (as the lines end at the brakes) it cannot get back out except when bled.

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GiveMeABreak
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by GiveMeABreak »

There's really no need to bleed the brakes when replacing the pads - you've probably now introduced air into the system as a result, so now you will need to properly bleed the system:

CAUTION:During the bleeding operation : Keep the fluid topped up in the reservoir and complete it. Use only clean fluid free from bubbles.
CAUTION: The ABS system must not be in operation during the bleeding procedure.

C5 MK I Bleed A.PNG
C5 MK I Bleed B.PNG
Front Brake Caliper: bleed screw(s).Rear Brake Caliper: bleed screw(s) .
Bleed each brake caliper in turn in the following order:
  • Front left-hand wheel
  • Front right-hand wheel
  • Rear left-hand wheel
  • Rear right-hand wheel
Bleeding Primary Circuit

N.B. : Two operators are necessary.
For each brake circuit:
  • Press the brake pedal to pressurise the system
  • Couple a transparent pipe on the bleed screw
  • Submerge the other end of the tube into a clean receptacle
  • Open the bleed screw
  • Wait until the fluid runs out free from bubbles
  • Close the bleed screw
  • Remove the bleeding equipment.
N.B.: Repeat a second time if necessary.
Check the brake fluid level (between the "DANGER" and the "MAX." levels).
If necessary, fill with approved and recommended synthetic brake fluid.

If you are still having problems, you may need to bleed the secondary brake circuit, for which you will need the use of diagnostic equipment and to follow the procedure.

deksa
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by deksa »

Thanks for the fast response guys!

"There's really no need to bleed the brakes when replacing the pads - you've probably now introduced air into the system as a result, so now you will need to properly bleed the system:"
Yes I know but I also removed the discs, and in order to do that I have opened the calipers so that is the air issue :(

"Front left-hand wheel"
With that you mean the driver side right?

"If you are still having problems, you may need to bleed the secondary brake circuit, for which you will need the use of diagnostic equipment and to follow the procedure."
What is the "secondary brake circuit"?

Also do you know why I have the fluid loss from the passenger front side? I like to mention that I have never opened that front side, I only worked on the rare brakes.

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GiveMeABreak
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by GiveMeABreak »

deksa wrote:
29 Nov 2018, 14:00
Thanks for the fast response guys!

"There's really no need to bleed the brakes when replacing the pads - you've probably now introduced air into the system as a result, so now you will need to properly bleed the system:"
Yes I know but I also removed the discs, and in order to do that I have opened the calipers so that is the air issue :(
"Front left-hand wheel"
With that you mean the driver side right?
These positions are as if sitting in the car - yes front left = driver's side on a Left Hand Drive Vehicle.
"If you are still having problems, you may need to bleed the secondary brake circuit, for which you will need the use of diagnostic equipment and to follow the procedure."
What is the "secondary brake circuit"?
This involves the ABS Block, so Lexia / Diagbox is needed - but hopefully you won't need it.
Also do you know why I have the fluid loss from the passenger front side? I like to mention that I have never opened that front side, I only worked on the rare brakes.
Without knowing where it is coming from it could be the brake fluid supply, the brake servo, a pipe, a bleed nipple etc. - I can't say from here. Surely if you tried cleaning it up around the leak you may be able to find the source. It might of been when trying to force the brake pedal down earlier when bleeding and there may be a weak joint or pipe damage / corrosion that the extra pressure of bleeding has made worse.

deksa
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by deksa »

One more thing please Marc:

What do you mean with "CAUTION: The ABS system must not be in operation during the bleeding procedure."?

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GiveMeABreak
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by GiveMeABreak »

It's just a general warning that the ABS system must not be operating during the bleeding procedure because of how the ABS system works and could force out brake fluid under high pressure. This normally won't be an issue - I just included it from the official guidance. :-D

lexi
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by lexi »

Not operating the abs means don't turn on ign while operations are in process. If you have let fluid escape from the ABS block and introduced air, then that is a further problem that may need diagnostic tool to purge. You just need to go over it again to fault find it.

deksa
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by deksa »

Yey I followed the given instructions for bleeding and these new brakes are insane! :)

About the fluid leak, it was the hydropnmeumatic oil, I miss 1cm oil in the reservoir, looks like that some of the hoses are leaking oil, but they are greasy from it and I cannot determine which one is it :(
Is it ok to use brake cleaner to clean them and check for the rupture? Or it will burn them out? If not, what to use for that purpose?
I doubt that it's the pump (thank god).

And again thank you all for the previous answers!

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GiveMeABreak
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by GiveMeABreak »

Just clean the oil away from the outside hoses with some warm soapy water if necessary and and a clean rag - then you should be able to determine where any fresh oil is coming from.

deksa
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by deksa »

I called a local Citroen service, they are full until tuesday, and they told me that the leak maybe a result from weather change warm/cold the hoses shrink and expand, that they will adapt in a few days.
Does that makes any sense?
The interesting thing is that right before I noticed the oil leak it was 10-15 degrees and on the day of the leak 0-5 degrees celsius.

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GiveMeABreak
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by GiveMeABreak »

Hmm, well I don't buy it personally, as they would have to design that into the system in the first place! If that was the case every winter there would be millions of Citroen owners with leaky hydraulics!

They are designed with some flexibility in, so unless a pipe / hose has been previously cut and shortened I think it unlikely.

deksa
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Re: Citroen C5 mk1 brake fluid leak after changing brake pads and discs

Post by deksa »

Sounds about right! :)
Will keep you posted.