natas

natas

Well-Known Member
This has been going on for a couple months and now I am totally lost.

Some time back I put power steering fluid in the brake master cylinder by mistake.
So I decided to change the entire system.
4 new calipers, new lines, new master cylinder and new valve thingy.
Everything installed and bled the brake at least a dozen times.
Some times I get a hard pedal, sometimes a soft.
then I ordered 2 different brake bleeding kits to reverse bleed.
did that about 10 times, same thing.
Changed the mastercylinder for the third time and now 9 times out of 10 the pedal is really hard and I almost have to stand on it to get her to stop, then other times (1out of 10) it goes almost to the floor with hardly any brakes.
One mechanic telling me its a servo vacuum problem, so I ordered both. They should be here at the end of the week.
Another mechanic says no it has to be a hydraulic issue.
I have already got over $3500.00 in new brakes and STILL no brakes.
What have I done wrong?

HELP!

Thanks.
 
Im no expert at all. But i had a right game with brakes some time ago.

Have you fitted the new servo and vacuum pump yet?

And do you think any remaining power steering in the pipes could have contaminated the new calipers causing air in, but no fluid out?
 
The vacuum pump and servo is on the way.

After I stripped everything I gravity bled the system quite a bit to get it clean, then did the install.
So there should be no contamination.
 
I was told to do a test.

Engine off, pump the brake pedal till hard then start the engine whilst keeping pressure on the pedal and it should slowly sink.
My pedal did not sink, it remained really hard.
 
natas said:
I was told to do a test.



Engine off, pump the brake pedal till hard then start the engine whilst keeping pressure on the pedal and it should slowly sink.

My pedal did not sink, it remained really hard.
Click to expand...


Sounds like you may have the answer then. Stick the new parts on and then try it!
 
Yup... sounds like a servo issue.

Just out of curiosity is PAS fluid that bad for a braking system? I mean obviously it shouldn't be used as a substitute for brake fluid, but if it's added accidentally surely it can't do that much harm? or can it? Power steering racks and pumps are made up of similar components and materials to brakes.
 
natas said:
This has been going on for a couple months and now I am totally lost.

Some time back I put power steering fluid in the brake master cylinder by mistake.
So I decided to change the entire system.
4 new calipers, new lines, new master cylinder and new valve thingy.
Everything installed and bled the brake at least a dozen times.
Some times I get a hard pedal, sometimes a soft.
then I ordered 2 different brake bleeding kits to reverse bleed.
did that about 10 times, same thing.
Changed the mastercylinder for the third time and now 9 times out of 10 the pedal is really hard and I almost have to stand on it to get her to stop, then other times (1out of 10) it goes almost to the floor with hardly any brakes.
One mechanic telling me its a servo vacuum problem, so I ordered both. They should be here at the end of the week.
Another mechanic says no it has to be a hydraulic issue.
I have already got over $3500.00 in new brakes and STILL no brakes.
What have I done wrong?

HELP!

Thanks.
Click to expand...

the hard pedal sounds like no vac assist from servo pressing pedal then switching on engine and pedal not sinking a little proves that, soft pedal is air or too much travel of pistons
 
Disc front and rear.

I have a friend on the island that is a certified diesel mechanic from GB, he used to do inspections for the MOT.
He came be last evening and we went under the Defender with a flashlight.
Sure enough we found brake fluid weeping/seeping/leaking out of the valve that controls the front and rear pressure. Very little moisture but its enough.
He also tested the servo, and it is not functioning.
So I will change the servo and order a new valve thingy.
He has assured me that I can still drive her , its just that the brakes are really heavy.

Thanks so much for all the advice and I will let you know how it turns out.
 
So servo and vacuum pump arrived.
We change the pump first and the old servo is now working fine.

However, I still have air in the line!!!
We have bled it more than a dozen times with no luck.
You would think that it is leaking but I cant find any on the floor where she is parked and have searched for moist areas.

any thoughts?

Thanks.
 
I dont trust any bleeding system mate, nothing wrong with the 2 person setup, pump lots through no letting the bottle empty in the front and surely it should work now, other than that id bite the bullet and change the lines and new connectors, a ball ache but surely there should be nothing stopping it working now.
 
IamRobbie said:
I dont trust any bleeding system mate, nothing wrong with the 2 person setup, pump lots through no letting the bottle empty in the front and surely it should work now, other than that id bite the bullet and change the lines and new connectors, a ball ache but surely there should be nothing stopping it working now.
Click to expand...


When you say "all the lines", do you mean all the metal lines?
All of the flexible lines that run directly to the calipers are new.
And, what connectors?

Thanks.
 
bloody hell, can't help think that the 'mechanics' seem a bit crap over there.

go clamp the flexies and see if the brake pedal improves. unclamp em one at a time to narrow the location down
 
trax said:
bloody hell, can't help think that the 'mechanics' seem a bit crap over there.

go clamp the flexies and see if the brake pedal improves. unclamp em one at a time to narrow the location down
Click to expand...


LOL, cant clamp as they are steel braided covered :eek:
 
natas said:
LOL, cant clamp as they are steel braided covered :eek:
Click to expand...

ack.. hmm even the one that goes to the rear brakes?.. goes from the chassis to the rear axle.

right pita, but you could get a spare brake union and pipe and fold the pipe over so it seals it off tight, then stick that on joints to cut off sections.

you'll introduce air, but least you can narrow down the area if it's a faulty part.
 
I might be stating the obvious here, but are all the callipers fitted with there bleed screws at the top?
 
When your foot is on the brake before starting it should be hard turn the engine on and it should soften and your foot should sink

If it doesn't theres a servo problem
 
200tdi ayre said:
When your foot is on the brake before starting it should be hard turn the engine on and it should soften and your foot should sink

If it doesn't theres a servo problem
Click to expand...


Servo was not working until I changes the brake vacuum pump, now it works fine.
But the servo would not cause the pedal to be sometimes high and sometimes low.

Everytime I bleed the brake there is always some air. I bleed until all air is gone. take her around the block, pedal goes to the floor (sometimes not).
Come right back and bleed again and there is STILL air in the line!!!!!
I parked her in the same spot for over a week to see if any fluid was leaking,,,,,Nothing????
 
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