natas Posted September 8, 2014 Share Posted September 8, 2014 A couple months back I put power steering fluid in my brake master cylinder by mistake. So I decided to change the whole system. 4 new calipers, new lines, new master cylinder and new valve thingy.\ Bled the brakes at least a dozen times and could not seem to get all the air out. Ordered 2 different brake bleeding kits, eezi bleed and some other reverse bleeder. Did that about 10 time, still a soggy pedal that sometimes got hard. Then I changed the brake master cylinder for the third time thinking that perhaps the master cylinder was at fault. Now, 9 times out of 10, the brake pedal is really hard and I have to push really hard to get her to stop. But then, every now and then (1 out of 10) the pedal will go to the floor with almost no brakes at all. So now the mechanic says that it has to be a vacuum pump or a servo problem. I ordered them and they should be here by the end of the week, Keep in mind that I am in the Bahamas and have to import all parts from the UK. Costly and it takes time. And another mechanic says that it has to be a hydraulic fault. I am at a complete lost. Help! Thanks. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted September 8, 2014 Share Posted September 8, 2014 Drums on the back? I can;t see it being a servo or vacuum pump, neither can have the direct effect of making the fluid disappear as you describe. My money would be on brake shoe adjusters doing something funky. Quote Link to comment Share on other sites More sharing options...
natas Posted September 8, 2014 Author Share Posted September 8, 2014 Disc front and rear. I am not loosing any fluid at all. she was parked for a week and I looked on the floor and there was nothing. I have brakes, kind of, but the pedal is very high and it is extremely hard to push, most of the time. Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted September 8, 2014 Share Posted September 8, 2014 Sounds like a malfunctioning servo to me. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted September 8, 2014 Share Posted September 8, 2014 Ah I am with you, mis-read something above, thought you were able to stop OK, but it failed and pedal went to the floor 1 time in 10... My reason for saying it is likely a hydraulic fault is because there's no way a failed servo would suddenly allow the pedal right to the floor, this must be hydraulic. Quote Link to comment Share on other sites More sharing options...
natas Posted September 8, 2014 Author Share Posted September 8, 2014 Sounds like a malfunctioning servo to me. This is what I am hoping for. Quote Link to comment Share on other sites More sharing options...
natas Posted September 8, 2014 Author Share Posted September 8, 2014 Ah I am with you, mis-read something above, thought you were able to stop OK, but it failed and pedal went to the floor 1 time in 10... My reason for saying it is likely a hydraulic fault is because there's no way a failed servo would suddenly allow the pedal right to the floor, this must be hydraulic. About 1 out of 10 times, the pedal will get soft and go almost to the floor with hardly any brakes at all. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted September 8, 2014 Share Posted September 8, 2014 Sounds like you may have two faults then, servo/pump and hydraulic. Quote Link to comment Share on other sites More sharing options...
natas Posted September 8, 2014 Author Share Posted September 8, 2014 One other test I was told to do. With the engine not running, pump the pedal till its hard then start the engine whilst you have pressure on the pedal. If the servo is working your foot should slowly sink. I tried this and my foot did not sink. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted September 8, 2014 Share Posted September 8, 2014 I have read that you can often finish off servos and/or master cylinders when bleeding as the pumping action employed can be too much for tired components. Bit of a pain! Not happened to me so far though... Yet! Quote Link to comment Share on other sites More sharing options...
ejparrott Posted September 8, 2014 Share Posted September 8, 2014 If the pedal didn't go down when you started the engine then there's a high probability the servo is shot. As said before though, you appear to have a hydraulic problem as well as a servo fault won't let the pedal go to the floor. If you've discs front and rear then we can rule out bad adjusters, as you've replace all callipers by the looks of it we should be able to rule out sticky pistons. Sounds as though the master cylinder seals might be letting by on occasion, but if you're on your third, that's pretty bad luck! Quote Link to comment Share on other sites More sharing options...
dailysleaze Posted September 8, 2014 Share Posted September 8, 2014 Check the wheel bearings for play. A slight wobble can push the pads back in Quote Link to comment Share on other sites More sharing options...
Boydie Posted September 9, 2014 Share Posted September 9, 2014 A tip for bleeding brakes, I just purchased a vacuum brake bleeding bottle, a hand pump evacuates the bottle, and when the hose is connected to any brake nipple the vacuum then sucks the fluid - and any air out of the line, if you can get your hands on one (beg, borrow or resort ot crime) they are the ants pants, the bottle will almost drain the master cylinder reservoir - so be carefull to keep it topped up to the lip. do this to the furthest brake from your master cylinder working your way to the closest. You can be assured that you will have clean fiuid and no air in the lines. Quote Link to comment Share on other sites More sharing options...
SvBeek Posted September 9, 2014 Share Posted September 9, 2014 Have had similar problems. A few tips: - if you have rubber brake hoses (not the ones with a metal mantle) clamp them one by one and see if the pedal is hard. When it does, you know which caliper(s) cause the problem. - press the pedal down and put a stick between it and the roof, to keep it clamped down. leave it overnight so all air bubbles have the time to find their way out - my 110 has drum brakes on the back, and if the shoes are not adjusted really close to the drums, the pedal doesnt always feel hard and its raises the suggestion that there is still air in the system while there is not. So i would check all your calipers again to see if there is nothing wrong with them. Are the pads close to the discs and not retracting too far? Are the correct pads fitted? Quote Link to comment Share on other sites More sharing options...
natas Posted September 9, 2014 Author Share Posted September 9, 2014 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. Quote Link to comment Share on other sites More sharing options...
ejparrott Posted September 9, 2014 Share Posted September 9, 2014 Question. Do you need the valve thingy? Is this the one that activates the brake switch or is it the mega expensive proportioning valve? Reason I ask, I and many others have ditched the one that operates the brake fail switch. Additionally, whilest sourcing parts for a possible 109 conversion, I found a set up that does not include the mega expensive valve thingy. Which is it, and could a grown up confirm if you actually need it! Quote Link to comment Share on other sites More sharing options...
natas Posted September 9, 2014 Author Share Posted September 9, 2014 Question. Do you need the valve thingy? Is this the one that activates the brake switch or is it the mega expensive proportioning valve? Reason I ask, I and many others have ditched the one that operates the brake fail switch. Additionally, whilest sourcing parts for a possible 109 conversion, I found a set up that does not include the mega expensive valve thingy. Which is it, and could a grown up confirm if you actually need it! Unfortunately it is the proportioning valve. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.