Help rear brake bleeding!
Thread Starter
Junior Member
Joined: Apr 2019
Posts: 63
Likes: 9
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Help rear brake bleeding!
Hi having a lot of problems trying to bleed up the brake on my C63. Changed the copper brake pipe that runs from from rear right wheel to left wheel arch area.
Cannot get the car to bleed up, I've bleed loads of cars up before and done the old fashioned method of a mate pressing the pedal down etc.
Front wheels push out fluid fine.
Rears literally hardly anything both sides!. Tried a vacuum pipe on both rear calipers today on the bleed nipples. Sucked loads of fluid through, under vacuum but not a constant flow.
But still no pedal. Pedal goes straight to the floor with a bit of resistance but can easily hit the bulkhead. I'm wondering if the master cylinder has blown when my mate was stamping on the pedal on first bleed?. The pedal is stiff on engine off though but as soon as engine is started it's when the pedal goes soft, it doesn't go down on its own just really soft.
Was going to buy a pressure bleeder tomorrow and try that, am I missing something on these cars?
Thanks
Cannot get the car to bleed up, I've bleed loads of cars up before and done the old fashioned method of a mate pressing the pedal down etc.
Front wheels push out fluid fine.
Rears literally hardly anything both sides!. Tried a vacuum pipe on both rear calipers today on the bleed nipples. Sucked loads of fluid through, under vacuum but not a constant flow.
But still no pedal. Pedal goes straight to the floor with a bit of resistance but can easily hit the bulkhead. I'm wondering if the master cylinder has blown when my mate was stamping on the pedal on first bleed?. The pedal is stiff on engine off though but as soon as engine is started it's when the pedal goes soft, it doesn't go down on its own just really soft.
Was going to buy a pressure bleeder tomorrow and try that, am I missing something on these cars?
Thanks
Super Member
Joined: Mar 2019
Posts: 522
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From: Bondi Beach , Australia
2013 W204 C63 AMG P31 Estate wagon
I've only used a pressure bleeder on mine.
Wondering if air has gotten into your ABS unit.
In my old car Holden HSV/Chevy SS you could electrically run the ABS to bleed out air.
Wondering if air has gotten into your ABS unit.
In my old car Holden HSV/Chevy SS you could electrically run the ABS to bleed out air.
MBWorld Fanatic!
Joined: Feb 2010
Posts: 5,649
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Since the system was opened you need to bleed the system by pressing the brake pedal. The operation must be done consistently and smoothly both in pressing the pedal down and letting it up. No jerky action or you might cause air to enter the system. You do not have to close the bleed screw during this operation. Continue until you have a smooth flow of brake fluid and no sign of any air bubbles. GL
From Alldatadiy:Bleeding the hydraulic system of the brake system: (after this was opened for repair purposes)
Depress the brake pedal repeatedly until fresh brake fluid flows out free of bubbles at the bleed screw (1) of the brake caliper.
To bleed the brake system correctly it is essential to pump the brake pedal throughout the entire bleeding process! Otherwise malfunctions and failure of the brake system can occur due to the remaining residual air!
In order to avoid the intake of air, do not pump the brake pedal in a jerking manner, but gradually release.
The bleed screw (1) at the brake caliper can remain open during the entire pumping procedure.
Required total volume of brake fluid: approx. 1.5 liter.
From Alldatadiy:Bleeding the hydraulic system of the brake system: (after this was opened for repair purposes)
Depress the brake pedal repeatedly until fresh brake fluid flows out free of bubbles at the bleed screw (1) of the brake caliper.
To bleed the brake system correctly it is essential to pump the brake pedal throughout the entire bleeding process! Otherwise malfunctions and failure of the brake system can occur due to the remaining residual air!
In order to avoid the intake of air, do not pump the brake pedal in a jerking manner, but gradually release.
The bleed screw (1) at the brake caliper can remain open during the entire pumping procedure.
Required total volume of brake fluid: approx. 1.5 liter.
Thread Starter
Junior Member
Joined: Apr 2019
Posts: 63
Likes: 9
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Still nothing been on it all day. Used a pressure bleeder got loads of fluid out of the calipers
Pedal hard when engine off, as soon as engine starts pedal is soft. Fronts seems to be biting well though.
I had the master cylinder off today, looks OK and pushing fluid out of the ports OK.
Maybe time to break it up
Pedal hard when engine off, as soon as engine starts pedal is soft. Fronts seems to be biting well though.
I had the master cylinder off today, looks OK and pushing fluid out of the ports OK.
Maybe time to break it up
