@anyone whos changed m/cylinder

[darkdezigns]

ok tin tin is having real probs as most of you know he changed his pad shoes etc changed his brake fluid etc,then brake pedal to the floor,new master cylinder from milners....still brake to floor,so another from milners.....brake hard without engine running,but still drops away with engine running,poor bloke is tearing his hair out,he did mention there seems to pressure on the pedal but right at the bottom,ie nearly touching the floor,screams of air in system to me,but he has bled it 5 times including the master,and he is losing no fluid atall,only thing i can think is gettin it pressure bled??
any ideas anyone?

[si tate]

Sounds like the only option left, if he's bleeding them in the right order, which im sure he is then a pressure test may not be the solution ether, but if your running out ideas then its worth a go.

[caney]

servo u.s perhaps

[bowella]

This might sound strange to you but it is a method I have used many times in the past when I have had difficulty in bleeding brakes (and clutch's for that matter).
Get a CLEAN squirt type oil can, fill it with new brake fluid, attach a flexible pipe to the spout, starting at the furthest point from the master cylinder, pump your squirt can untill you have fluid coming out of the pipe so you don't pump any air into the system, slacken the bleed nipple and pump a good quantity of new fluid into the system, effectively "back" bleeding the brakes, have something under the master cylinder tank, with the filler cap removed, to collect the fluid that you will displace by pumping in the new fluid "backwards".
Repeat at all the other bleed points untill you have done them all, try to make sure you pump at least 1/2 a squirt can through each nipple, this usually does the trick by pushing the air out through the master cylinder.
I have used this method many times, especially on Volvo truck clutch's which are a sod to bleed, and this is the only method I have found to work every time.
Hope this helps, you have nothing to lose by trying it apart from some brake fluid.
Best regards and I hope it works for you, John.

[surfenstein]

ah,beaten to it,as bowella said try back bleeding the brakes.or wedge the brake pedal down overnight and try re bleeding in the morning,

[darkdezigns]

hopefully alan will be on soon to read this,cheers guys

[tintin]

Since i spoke to Andy, i put the wheels back on, took it for a spin round the farm, brakes felt really sharp at first, but have softened slightly since.
Drove home ( about 3 miles) still have the original problem!
No signs of any fluid loss at any point.
Last week, clamped off all 3 rubber hoses to eliminate all wheels.
Changed all the hoses today to braided (while i had the system drained)
I have bled the system 5 times today , and there are no air bubbles at any of the 5 bleed points.
So I will try the 'stick to hold the pedal down' trick tonight.
If that doesn't work i will phone round to find somewhere to pressure bleed!
Thanks for all the advice guys (especially Andy, sorry to bother you on a sunday mate)
Will let you know what happens
Alan

[surfenstein]

dont forget to tie the load sensing valve up either,remove the curved rod from the bracket on the panhard rod and tie it up as high as it will go.

[tintin]

I've done the stick, but it's too late and too dark to be getting under her now Mark!
If theres no change when i get home from work ( about 6.30 ) tomorow, i'll try that as well tomorow night!
Thanks mate.
( and thanks Bowella too )

Alan

[Diezel Weazel]

Bear with me... But in my early mechanical engineering days (late 60's-early 70's)
If we were fitting a Master Cylinder - Brake or Clutch ya had to bleed the master cylinder first before fitting it (fill M/cylinder with fluid n manually hand pump (don’t let fluid to run out of reservoir) until pressure is felt n fluid emits from pipe fitting connection.(with fluid in M/cylinder & top on) Fit to Vehicle.
Re- Connect all pipes to master cylinder.
(Without engine Running) Start at the furthest bleed nipple open slightly so ya can just see weeping fluid (keep an eye on Fluid reservoir n top up as is necessary, DO NOT LET FLUID RUN OUT)
Locking each nipple up after fluid runs free, do this to all nipples finishing at the nearest to the M/Cylinder.
After this procedure Gently check foot pedal, NO ENGINE RUNNING…

Step 2
As in the old days I prefer to finger bleeding Technique. (Gentle pressure with tip of finger over nipple)
WITH ENGINE RUNNING! Get someone gently presses the brake pedal the pressure will force ya finger of the nipple allowing the fluid to escape. Get the brake person to Shout DOWN n then lock the nipple each pump (finger still in place over the nipple) Keep checking reservoir Fluid level.
Do this in the sequence described earlier, furthest away first …finishing up at the nearest, last.
CHECK N TOP UP RESERVOIR FLUID before Testing the Brake pedal.
Job should be a good en!
Good Luck Alan

There's always a Payback .... Just don't expect any warning !!!!

[darkdezigns]

Since i spoke to Andy, i put the wheels back on, took it for a spin round the farm, brakes felt really sharp at first, but have softened slightly since.
Drove home ( about 3 miles) still have the original problem!
No signs of any fluid loss at any point.
Last week, clamped off all 3 rubber hoses to eliminate all wheels.
Changed all the hoses today to braided (while i had the system drained)
I have bled the system 5 times today , and there are no air bubbles at any of the 5 bleed points.
So I will try the 'stick to hold the pedal down' trick tonight.
If that doesn't work i will phone round to find somewhere to pressure bleed!
Thanks for all the advice guys (especially Andy, sorry to bother you on a sunday mate)
Will let you know what happens
Alan

no worries matey,anytime

[tintin]

Bear with me... But in my early mechanical engineering days (late 60's-early 70's)
If we were fitting a Master Cylinder - Brake or Clutch ya had to bleed the master cylinder first before fitting it (fill M/cylinder with fluid n manually hand pump (don’t let fluid to run out of reservoir) until pressure is felt n fluid emits from pipe fitting connection.(with fluid in M/cylinder & top on) Fit to Vehicle.
Re- Connect all pipes to master cylinder.
(Without engine Running) Start at the furthest bleed nipple open slightly so ya can just see weeping fluid (keep an eye on Fluid reservoir n top up as is necessary, DO NOT LET FLUID RUN OUT)
Locking each nipple up after fluid runs free, do this to all nipples finishing at the nearest to the M/Cylinder.
After this procedure Gently check foot pedal, NO ENGINE RUNNING…

Step 2
As in the old days I prefer to finger bleeding Technique. (Gentle pressure with tip of finger over nipple)
WITH ENGINE RUNNING! Get someone gently presses the brake pedal the pressure will force ya finger of the nipple allowing the fluid to escape. Get the brake person to Shout DOWN n then lock the nipple each pump (finger still in place over the nipple) Keep checking reservoir Fluid level.
Do this in the sequence described earlier, furthest away first …finishing up at the nearest, last.
CHECK N TOP UP RESERVOIR FLUID before Testing the Brake pedal.
Job should be a good en!
Good Luck Alan

There's always a Payback .... Just don't expect any warning !!!!

Basically i've done all this (albeit with an 'EASIBLEED' and an assistant) except bleeding with the engine running!!!!!!
Will this make any difference, as no-one seemed to think it necessary last week!!!
Thanks
Alan

[surfenstein]

if you have the engine running it will use the servo to assist in pumping the fluid through your brake system,but just be gentle on the pedal when bleeding,its not a neccessity,but it might help.

[tintin]

Will give it a bash 2moro night!
(yippeee, brake bleeding by torchlight at the roadside)
Thanks all
Alan

[darkdezigns]

cant say i have ever tried with engine running,but running out of ideas gotta be worth a go,but as surfnsnatchy said go easy on the pedal,i now have a mental pic of alan watch his brakefluid spray across the road