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Hard Brake Pedal... cause and fix

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Old Jun 29, 2013 | 01:11 PM
  #1  
iambhooper's Avatar
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Mudding
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From: Greensboro, NC
Default Hard Brake Pedal... cause and fix

Ok, so a few of you may have noticed a few of my posts in other threads about bleeding the brakes, and pedal feel. I have some thing's going on that don't make sense, based on my general auto repair knowledge (i'm a decent race car mechanic)... so here's where we started, what we did, and where were at (and I say we cause I have some reliable, non-rover tech help):

'99 DII, 170,000 miles, I've had it for about 7000 and maintained well since then.

1st, the brake pedal initially required a double pump to build up pressure. My tech recommended rebuilding the master cylinder, and a kit was ordered from Land Rover. He rebuilt it and told me he bled the system like I asked.

While this was going on, I pulled the ABS module and affected repair B in an effort to fix the tres amigo's.

The result was a truck that was impossible to stop. Both feet were required to get the pedal to work.

It was then determined that the brake booster must be bad (how one just stops working I will never know, but WTH), so in a fix, I picked one up at a salvage yard

This didn't fix the problem, so I called Paul Grant and ordered another booster (thanks, BTW!) and have installed that today.

Result? Same hard pedal.

What am I missing? I pulled the master cylinder to look at it, but since I have nothing to compare it too, I don't know. There is some firmenss to the piston, but am not certain if thats too much or too little.

Needless to say, I'm pissed. I've been without my truck for a while now, and need it ASAP, so I can haul a few things.

Thanks!
hoop
 
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Old Jun 29, 2013 | 01:35 PM
  #2  
frankieoboy's Avatar
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From what i've read, your initial problem might have been swollen (swelled ?) flex tubes or air in the system.

I suppose you used compatible brake fluid and checked the vacuum line ?
 
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Old Jun 29, 2013 | 02:20 PM
  #3  
Disco Mike's Avatar
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You either did not rebuild the M/C correctly and or the rod from the booster needs to be readjusted.
 
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Old Jun 29, 2013 | 05:32 PM
  #4  
iambhooper's Avatar
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Mudding
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From: Greensboro, NC
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Originally Posted by Disco Mike
You either did not rebuild the M/C correctly and or the rod from the booster needs to be readjusted.
You know, I am starting to think that. I pulled the master cylinder back off and looked it over, however since I'm not the one that rebuilt it, I have nothing to compare it to. I bench bled it again and reinstalled it. Also, my partner had a surprise for me and had a new vacuum tube and fitting for the booster.

We bled the system some more, first bleeding the module, then manual bleeding each corner in sequence. The result was a better pedal, but still not one I'm comfortable with letting my wife drive.

Mike, learn me a bit about adjusting the rod... . Icouldnt find anything about that and nine of my techs are knowledgeable about rovers.

Thamks!


Oh, and I am missing mytruck!
 
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Old Jun 30, 2013 | 01:59 PM
  #5  
SuperSport's Avatar
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Isn't there also some type of separate method of bleeding the ABS system after pulling it? I think I've read that somewhere...
 
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Old Jun 30, 2013 | 03:30 PM
  #6  
bballjames's Avatar
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From: Las Vegas
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Originally Posted by SuperSport
Isn't there also some type of separate method of bleeding the ABS system after pulling it? I think I've read that somewhere...
I know my Hawkeye will bleed the ABS module. I'm not sure if it can be done without some type of scanner/computer.
 
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Old Jun 30, 2013 | 03:34 PM
  #7  
iambhooper's Avatar
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Mudding
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I must have left that out, I have bled the ABS with Maxidas. I'm still confused about what Mike said when it comes to readjusting the booster rod.
 
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Old Jun 30, 2013 | 03:53 PM
  #8  
ralphobell's Avatar
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From: Austin, TX
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I have removed my ABS unit twice and have followed the RAVE each time and had no issues.
 
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Old Jul 3, 2013 | 03:00 PM
  #9  
iambhooper's Avatar
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Mudding
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From: Greensboro, NC
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Ok, here's the update...

first, I would like to thank Paul Grant for sending me a brake booster to try wit the "rebuilt" master cylinder.

second, I would like to thank Paul Grant for sending me a master cylinder to use with the brake booster he sent earlier!

Today, I installed the master cylinder, vacuum bled the system, bled the module, vacuum bled, force bled the system twice and now have the best brake's that I have had in the rover!

Thanks again for all the help!
 

Last edited by iambhooper; Jul 3, 2013 at 03:04 PM.
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Old Sep 1, 2019 | 08:48 AM
  #10  
SanduPanus's Avatar
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I am starting to have a noise when I press the brake pedal hard. then, for 1-2 seconds I have no vacuum...

if I press the brake pedal gently, everything is fine and the brakes are working normal.

I expect one part is starting to break. what should I suppose? Brake Booster? Or Master Cylinder?
D2, Auto, Td5.
 
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