Brakes - symptom

[minorissues135]

Hi, so after bleeding several times, this is what I get. First press, pedal near to floor, second press, pedal half way and firm. Brakes working well or seem to be.

Replaced m/c, all slaves, flexi pipes, copper pipe across axle. Bled x3, going from furthest from m/c to nearest. Realise now it has a servo, pipe goes from side of m/c (back outlet blanked off, no leaks), to front, junction, into servo and out.

I guess somehow I bleed the lines around the servo or servo itself? Any suggestions as to the best way to do this appreciated. TiA

[daveejhitchins]

Hi, so after bleeding several times, this is what I get. First press, pedal near to floor, second press, pedal half way and firm. Brakes working well or seem to be.

Replaced m/c, all slaves, flexi pipes, copper pipe across axle. Bled x3, going from furthest from m/c to nearest. Realise now it has a servo, pipe goes from side of m/c (back outlet blanked off, no leaks), to front, junction, into servo and out.

I guess somehow I bleed the lines around the servo or servo itself? Any suggestions as to the best way to do this appreciated. TiA

Might be good to see a photo of your servo - just to check it's fitted correctly!

Dave H.

[Bill_qaz]

Are you on drum brakes or discs, are your drum brakes adjusted ?
1st pump could be taking up shoe to drum clearance, obviously discs are self adjusting.
Fluid should pass through the servo and not effect bleeding unless servo is incorrectly mounted and you have an air bubble.
As stated in other reply a picture would help
As an example my servo is only on the front circuit to the disc brakes.

[minorissues135]

All drums, properly adjusted.

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Brake pipe comes in from master, up to servo, out from end of servo and down to a junction piece then on to both back and front. I'll post a few photos here, if there are any other perspectives that will help let me know and can post tomorrow.

Highest point seems to be the big banjo bolt end, the 'out' pipe from servo. Generally the advice seems to be that air will get trapped at the highest point, also this has a nice big bolt on it rather than a union so should be easier to open and bleed.

As mentioned, these parts replaced and bled 3x times: Master, all slaves, flexi pipes, back pipe across axle, new large snail cams on front, synthetic brake fluid and 2x new rear drums (cleaned before use). Shoes in good condition again cleaned, no contamination.

The only thing I did just notice, is that the pipe exiting the master cylinder goes up and over the frame member - what I'm thinking is, what happens to the air in it? Would it get pushed along and out, or bubble back up again to sit there? Last time I drove it before the work, the pedal was fine, although I realised only 3 wheels were actually being braked.

[Bill_qaz]

Have you tried bleeding with the engine running, so the servo is pushing the fluid rather than it just passing through unassisted. You could try pumping the peddle and holding the pressure then cracking the banjo bolt you referred to, re-tighten before releasing pedal.
Sometimes jacking the rear as high as possible to make bleeder highest point can also help.
Do you have access to a vacuum bleeding tool to suck the fluid through the bleed nipples.

[minorissues135]

Hi, thanks for the advice. Not tried bleeding yet with engine running. Will try first bleeding at banjo bolt engine off, if that doesn't work, will do same engine on. If not joy then, will try cracking open other union junctions points and do same.