Kennymac

Active Member
Evenin folks,

Having replaced the whole brake system (all pipes, master cyl, all flexis, all calipers, inc T-piece) I still can't get a pedal. All joints have been checked for air/fluid leaks) all bleed nipples have been checked, flexi's have been locked off and others bled, no air is coming out in fluid. Fluid level in master cylinder doesn't change.

System has been drained and re-filled (by gravity) and bled again. I even had a mate bleed it who knows a bit about landies, and no one can figure why the pedal won't come up (it'll form a pedal after 3/4 pumps, but it falls back down after that).

Anyone come across anything like this before? Or am I going to have to take it (carefully) to the garage?
 
if the pedal moves after being pumped up it sounds like the master cylinder seals are leaking and requires either a strip down and new seals or a new cylinder, as a further check if the seals have gone the brake fluid usually turns a dark / and or black colour, which is evidence of the seals breaking up
 
Hi Si,

the master cylinder is brand new, just out the box - the fluid comes out clean, no particles or crap in it. However, I guess I can't ignore the possibility that the new one I bought was buggered...

The freaky thing is. If I lock any 2 of the 3 flexis off - I get a rock solid pedal.
I'm at my wits end!!

cheers
K
 
Don't know about cars too much (never done a full rebuild on the brakes) but after fitting new brake lines to a bike they are always a complete biatch to bleed up, I usually find it easier to use a syringe to push fluid back uphill to the res.

In some cases there is an extra bleed point just below the master cylinder, and you have to bleed this first.

Just fitted braided lines to my mates SP2 last week and spent 3.5 out of the 4 hours bleeding them, the technique that eventually seemed to work best was:

Manual method - forget about eezi bleeders...
Nipple closed, pump away at brake 10-15 times then hold
Nipple open then closed, repeat...

Sounds like there is definitely still air in there somewhere!
 
Hi

From what you say, I would say either - the master cylinder you have fitted is defective or there is air in the system somewhere.

The absolute best way of bleeding brakes on your own is with a vaccum pump.

they do cheap ones and they do good ones - simple to use - fill your res to the top, fit the vac pump on the nearest nipple, open it and pull through until its pure fluid - keep an eye on the res and keep toppin it up, then go to the next furthest away and so on.

It will work, and works (from many years of experience) better than a liquid lever (posh name for an easybleed).

HTH
Westy
 
Westy - right, I'm up for that - where do I get a vacume pump or brakes from?
Do they have a trade name (like eezeebleed etc?)

Thanks in advance!
K
 
Well, I got mine from my Snap On dealer about 13 years ago, but a quick search on Google found this amongts others ..........

Amazon.co.uk: FRANKLIN Vacuum Brake Bleeder (AF404): DIY & Tools

But I cannot comment on the quality of this particular item. Franklin are OKish DIY gear so should be OK.

Just thought on - you will need an air compressor to use this sort of pump. There are small hand vaccum pumps which will configure to do the same thing, but they dont work as well - the vaccum they produce is not as constant, but a quick google search for ' hand held vaccum pump ' , with the uk search option selected, will find you some.

HTH
Westy
 
Does it do this while stationarty, or while moving? Cos if while moving, one of your, (new) discs could be warped.
 
Westy - Thanks for that, I'll give it a shot. I've got a compressor, so that should do the job nicely.

Boydy - No, haven't had it moving, this feker hasn't left the garden in months!

Thanks!
K
 
No worries Kenny

It will also come in handy for bleeding the clutch system, and also does a good job of draining fuel systems, coolant systems - just about anything.

Cheers
Westy
 
Evenin folks,

Having replaced the whole brake system (all pipes, master cyl, all flexis, all calipers, inc T-piece) I still can't get a pedal. All joints have been checked for air/fluid leaks) all bleed nipples have been checked, flexi's have been locked off and others bled, no air is coming out in fluid. Fluid level in master cylinder doesn't change.

System has been drained and re-filled (by gravity) and bled again. I even had a mate bleed it who knows a bit about landies, and no one can figure why the pedal won't come up (it'll form a pedal after 3/4 pumps, but it falls back down after that).

Anyone come across anything like this before? Or am I going to have to take it (carefully) to the garage?

If the brake goes solid when you clamp the pipes then it aint the master.

If you clamp the front two that illiminates the calipers, and if you clamp the rear flexi's same again that rules out the brakes, shoes or calipers whatever is on it.

When you pump the pedal up and it goes solid, if you maintain that pressure does the pedal remain solid until you release and press again, or does it fade away.

I will see if my cd has a diagram
 
Evenin folks,

Having replaced the whole brake system (all pipes, master cyl, all flexis, all calipers, inc T-piece) I still can't get a pedal. All joints have been checked for air/fluid leaks) all bleed nipples have been checked, flexi's have been locked off and others bled, no air is coming out in fluid. Fluid level in master cylinder doesn't change.

System has been drained and re-filled (by gravity) and bled again. I even had a mate bleed it who knows a bit about landies, and no one can figure why the pedal won't come up (it'll form a pedal after 3/4 pumps, but it falls back down after that).

Anyone come across anything like this before? Or am I going to have to take it (carefully) to the garage?

Had to look to see what kind of motor it was, drums on the back?

If you have made a coont of the rear brakes, adjustment, wrong shoes or cyliners, built up wrong, that would cause this fault, but clamping the rear flexes will illiminate it.
 
Just a quick update, managed to borrow a fluid sooker from the local garage, and it worked a treat. Full pedal now, brakes working better than they ever did before! Thanks for the help!!
K
 

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