Breaking Woes


Not sure what is wrong with my Landy. I leave in 48 hours for a 1700 mile move. I have seen others with similar issues, but no real resolution. Here's the series of events as they happened:


December 2012: Was driving my Landy and no break pedal pressure (pedal goes to the floor), and VERY limited stopping power. It was “two pumps and a prayer”. Was told this could be a possible Master cylinder issue. Notice break lines have leaked fluid everywhere. Put more fluid into the MC and limp it home.


January 2013: Partner is in town and replaces the master cylinder and both front break lines. He bleeds the front breaks. In hindsight he needed to bleed all 4. The next day we drive it around and notice the breaks feel “spongy”. Like you're pulling a loaded trailer. We drive it to a conference 70 miles away. On the way to the airport (this was another 70 mile trip), breaks are either spongy or the pedal is very hard (like you put the car in park, and pump the breaks until they are hard).


Partner goes to the airport and says, “don't use the breaks, you'll be able to drive it home”. Ok, I didn't use the breaks (it was 4 am, no one was out of the freeway). I'm going up a pass incline and notice my truck is very slow to accelerate window is up, so I don't smell the breaks either. I pull over and see they are on fire. Calmly extinguish the fire. I carry an extinguisher in my truck. Tow the truck home.


May 2013: Note: truck was not driven for a period of 4 months. Waiting until I collected parts to change out. Get a mechanically enabled friend to come work on my Landy. We replace the rotors, break calipers, pads, break lines (again), new ABS manifold. Bleed all 4 breaks very well. Go through lots of DOT 4 fluid. The old, damaged front passenger pads were completely gone and the rotor was shaved down about half it's original width. Drive Landy around for a few minutes all seems well. The next day I drove it, needed a new battery, but an auto store was not far away. Drove a total of 10 miles that day.



Yesterday: (The following day), was driving over another hill incline and the breaks seized again. The truck was not accelerating up the hill like it should have, and the break pedal was very stiff. I had the window open, there was that smell of the pads.


I pull over, turn the engine off, and remove the 30 amp ABS fuse. I didn't have a screwdriver for the 40 amp. Start the vehicle back up and the break goes back to normal. Ok, so I drive it home and think about it. Removed the 40 amp ABS pump fuse.



Today: My other friend is over to help me move, and we drive to the to get the moving truck, 9 miles away. 5 miles into the trip, the breaks seize up once again. I pull over and turn the car off. Wait 5 minutes. Turn the car back on and the break pedal returns to normal pressure and I drive the vehicle into the nearest parking lot (which was the Hardware store). No break fluid leaks anywhere.


I unplugged the ABS manifold and drove it 4 more miles to the moving truck depot, then 9 miles back home. No problems then. My mechanically able friend comes over later that day, and removes the third ABS fuse (which I didn't know about, the one under the dash). We drive 30 minutes, in various conditions, 15 miles total (longest distance so far and time too). No problems.


Was this an ABS issue or is it something else? I'm VERY nervous driving this vehicle cross-country, and am scared of an issue happening in the desert. I'm fine with driving without ABS.


Futher Background info: The abs sensor in the wheels were bad when I bought the truck (used of course) in February 2011. I have learned this is common in Disco 1's.



No caliper pulling. When I let go of the steering wheel and break, the truck continues in a straight line. Tried this at various speeds ranging from 20-65 mph.



Not sure if ABS, power break booster or something else entirely that I'm missing? Bleeding breaks once again tomorrow to be sure/safe. Worried about the trip.

 

1. You waited too long to address this problem.

2. It's "BRAKES" and not "BREAKS".

3. Replace the Master Cylinder with a Genuine Land Rover part. You have a non-genuine part and this is exactly what they do, lock up the brakes.

4. ABS will cause the accumulator to over-modulate and you'll have a rock hard brake pedal that you have to use all your weight with to stop the truck. It does not lock up pads to the rotors nor grind either to nothing in a short time span.

5. You'll survive the trip but it will be allot less fun wondering when the brakes are going to lock. Doing 75 - 80 will wear them down really fast......carry a fire extinguisher.

 

Thank you for the advice! Any particular reason why non genuine MC lock the breaks?

 

No, but they do.
Do you still have the original Master Cylinder? I'd say put that back in unless you know 100% it was bad. But to me it sounded like you just blew a brake line back in Dec '12.

 

I'll have to see if the original was kept and if so, I will take it with me then. Wondering if the master cylinder release the brakes if I turned off the car and restarted it (releasing the breaks on restart)? To me that seems like an electrical issue (which may be the MC).

 

MC electrical is just the fluid level switch. No "reset on power up".

 

No engine vacuum to the brake booster...... If you want to split hairs it's electrical, you switched off the ignition to cut the engine.

I'd replace the MC BEFORE you left.... seems allot smarter to me but WTF do I know......maybe you like worrying your **** off for 1700 miles. Some folks get off on S&M. My GF really gets off when my hands are around her neck so by all means have at it. I choose DOMINATE!!!

Hehehe......just noticed this was my "666"th post, gotta be a sign.

 

I'll see tomorrow if the original master cylinder is still around and if it is, put it back on Landy. As far as S&M goes, different strokes, different folks, who am I to judge?

 

My friend , it sounds like your ABS modulator is toast ,take it out since you are ok to drive without abs brakes , this is D1 there is no traction control on it ,you will just gain good brakes .

 

I've seen this issue numerous times on different vehicles. You may be okay with the current master cylinder, but you need to check it's dimensions. This issue is most commonly caused by too little freeplay between the booster pushrod and the master cylinder. If there is any pressure put on the master cylinder piston when it is bolted to the booster it blocks the compensating port in the master. When this happens the fluid is not allowed to bleed back to the reservoir. Driving with it like this causes the fluid in the calipers to heat up. When the fluid heats up it expands, but with the compensation port blocked it has nowhere to go so it applies the caliper piston thus causing more heat and expansion until the brakes lock. Once it cools off the cycle starts again. If the master is rebuilt correctly you may be able to use it.


Remove the master cylinder and measure from the mating flange to where the booster pushrod mates to the MC piston. Then measure the mating surface of the booster to the face of the booster pushrod. You should have clearance to ensure the master can return all the way. I'm not sure exactly how much clearance you should have, I would guess .010-.012 would be sufficient.