Brake master Cylinder
Brake master Cylinder
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Discussion

R0162

Original Poster:

2,435 posts

193 months

Sunday 22nd January 2012
quotequote all
I wasnt happy with the brakes on the car which i put down to the EBC yellowstuff the car was stpping but just not as aggressively as i would have liked, so i put DS 2500 bedded them in and there was no difference, still the pedal was lacking feel, no big issues the pedal was a little bit spongy but nothing to imply a major problem.
So i took the car to get the brakes bled, he used a machine that pressurizes the system and pumps brake fluid through, and we could visibly see some little bubbles in the fluid. After this the brake pedal was firmer as to be expected, but after an hour of driving the pedal became very spongy, so as it stands i have to press the pedal twice before it becomes firm.

I'm not sure what could have happened, the pedal was initially firm after bleeding the brakes, so maybe it is conincidence that the master cylinder has gone only minutes after bleeding the brakes or whether something else could be going on.

Gadgeroonie

5,362 posts

265 months

Sunday 22nd January 2012
quotequote all
did you have to pump the pedal when you bleeded it ?

the extra movement with no load on the cylinder can make the rubber scratch on a section of cylinder that was not smooth and it rips the rubber

all you can do it bleed it the conventional way and see if the problem goes away

R0162

Original Poster:

2,435 posts

193 months

Sunday 22nd January 2012
quotequote all
Hi Mike, are you talking about a cylinder rubber on the master, or on the calipers?

I did not have to pump the pedal after bleeding, i will try to bleed it the conventional way, maybe it managed to pull air in from somewhere or maybe the master has gone.

If i need a new master do you have any idea what make they are and how much they cost, or would it be one of those items i would have to get direct from Noble?

Gadgeroonie

5,362 posts

265 months

Monday 23rd January 2012
quotequote all
Hi Chris

talking about the master cylinder rubber

its almost certainly a ford part


FUNKSTER UK

765 posts

231 months

Monday 23rd January 2012
quotequote all
Gadgeroonie said:
Hi Chris

talking about the master cylinder rubber

its almost certainly a ford part
I think you'll find its AP along with the rest of the system,

I rebuilt mine after a leak with parts that AP can't supply...... But did :-)

funkybmx1

958 posts

223 months

Monday 23rd January 2012
quotequote all
FUNKSTER UK said:
Gadgeroonie said:
Hi Chris

talking about the master cylinder rubber

its almost certainly a ford part
I think you'll find its AP along with the rest of the system,

I rebuilt mine after a leak with parts that AP can't supply...... But did :-)
And u ain't used it since so what's that saying lol smile

FUNKSTER UK

765 posts

231 months

Monday 23rd January 2012
quotequote all
funkybmx1 said:
And u ain't used it since so what's that saying lol smile
Cheeky Bloody git!

Your right though..... Just keeping the mileage down until my power to weight improves....

The Csl doesn't mind the extra few pounds biggrin

Tele Matster Savalas

R0162

Original Poster:

2,435 posts

193 months

Monday 23rd January 2012
quotequote all
I got a price from SWLC today, £282+vat, it is AP.

Before i ordered a new one though i thought i would have a go at bleeding the brakes myself the conventional method and the problem is now fixed.
Seriously a set of turnips over here, its mind blowing, seems they had forgotten to bleed one of the inside fronts.

The brakes are stopping the car ok, still not amazing though, not as i remember when i first got it with the AP pads on, maybe the master cylinder loses a little over time?

Gadgeroonie

5,362 posts

265 months

Monday 23rd January 2012
quotequote all
do you have the vacuum line attached to the servo ?

R0162

Original Poster:

2,435 posts

193 months

Monday 23rd January 2012
quotequote all
Gadgeroonie said:
do you have the vacuum line attached to the servo ?
Good question, i will check as soon as i find out what a servo is and what it looks like smile

R0162

Original Poster:

2,435 posts

193 months

Wednesday 25th January 2012
quotequote all
I found an issue, tne EBC yellow stuff pads are larger than the Original AP, i put new grooved discs on the front whe i fitted new pads but i left the original drilled discs on the rear in hindsight i should have left the original AP pads on the rear also, the rear discs had a raised lip on the outer edge which the EBC pads fouled as they protrude past the outer perimeter of the disc, over time the pads had worn down the raised lip a little but the lip was still stopping the pads from having good contact, so i took off the remainder of the lip with the dremel....then i took the car out to bed the pads back in and now they are getting good contact, the pedal feels firmer and the pads are giving more bite in relation to foot pressure.

Gadgeroonie

5,362 posts

265 months

Wednesday 25th January 2012
quotequote all
Pressure = Force / area

the larger area has affected the efficency of the brakes

the same thing happens with Tyres - you go wider than optimal and you reduce grip