No brake pressure with torque, poor pedal feel

mezje

Leaving Skid Marks
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Melbourne
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Maxim
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1998 Galant VR4 Manual
As per title I get no brake pressure when moving i.e. there is torque at the wheel. The brakes work and bite while the car is moving at very low speed (almost a stop) however when moving I feel the tiniest amount of pressure and then nothing.

I suspect it is the master cylinder and have one on order, but I thought I would throw this one to the brain's trust whilst I am away for work. I'm thinking the booster transfers pressure to master cyl but master cyl has an internal leak. Hence I feel a small amount of pressure that then dissipates.

Worth noting:
  • I rebuilt my brembos when reshelling my car and moved on to the new one, booster and master cyl retained.
  • There are no leaks and I have bled the system more times than I care to admit, using 1.5L of brake fluid (in a bid to fix the issue)
  • https://www.ozvr4.com/threads/poor-braking-performance.15842/post-340028
    I can get pressure and exhibit what @Kaldek details here, so I don't think it is the booster.
Thoughts?
 

Marko

Idling at the Lights
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QLD
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Mark
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Galant VR4
Had the same issue with my Brembo’s. Turns out I hadn’t bleed the brakes properly, there was another set of bleed screws on the inside of the front calipers. I had only done the outside and air was caught on the inside set of pistons. It was a rookie mistake on my part, but worth a look.👍
 

mezje

Leaving Skid Marks
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Maxim
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1998 Galant VR4 Manual
Had the same issue with my Brembo’s. Turns out I hadn’t bleed the brakes properly, there was another set of bleed screws on the inside of the front calipers. I had only done the outside and air was caught on the inside set of pistons. It was a rookie mistake on my part, but worth a look.👍
This is a very good point. I have definitely only bled from one point.
 

BCX

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2000 Galant Type-V
1997 MK Triton GLS [6G74 conversion]
2019 i30 N-Line
My rear calipers have a bleed for the inner cyl too.

When you bleed each caliper, start with the outer then move to the inner.

Wheel order:
  1. Rear left
  2. Front right
  3. Rear right
  4. Front left
 

mezje

Leaving Skid Marks
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Maxim
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1998 Galant VR4 Manual
My rear calipers have a bleed for the inner cyl too.

When you bleed each caliper, start with the outer then move to the inner.

Wheel order:
  1. Rear left
  2. Front right
  3. Rear right
  4. Front left
Yeah roger, had done that, just neglected the inner bleeders - amateur hour!
 

Baba Galant

Leaving Skid Marks
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John
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Galant VR4 twin turbo 1997
My rear calipers have a bleed for the inner cyl too.

When you bleed each caliper, start with the outer then move to the inner.

Wheel order:
  1. Rear left
  2. Front right
  3. Rear right
  4. Front left
Is that the bleed order for our car's or only if fitted with Brembos?
 

BCX

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2000 Galant Type-V
1997 MK Triton GLS [6G74 conversion]
2019 i30 N-Line
Evo and galant have the same order.

The master cyl has two circuits, and its to do with bleeding a circuit at a time.

Rear left, front right are part of one circuit.
Rear right, front left are the second.
 

mezje

Leaving Skid Marks
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Maxim
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1998 Galant VR4 Manual
Well not sure if it was the master cyl or the fact I hadn't bled the inner bleeders.

Car now brakes as it should, almost ready for RWC and club reg!

There was a bit of corrosion on the booster and below but that could have been from previous brake fluid top ups, no obvious damage to the old master cyl and no leaks when I was checking it.
 
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