Souster

Hi All Hope you all had a good Christmas! Today, I decided to remove the drivers side front caliper, while still connected. Put two old pads between existing pads (to act as a disc) tie the caliper out the way. And take it for a small drive on private land. I planned to do this both sides, and whichever caliper removed didn't show the pedal sinking on cornering was the problematic corner. Anyway, it didn't seem like a very good test. As I was too wary of the security of the caliper. However, the pedal did seemed to me more spongy. I'm wondering of that was due to the bends in the flexi pipe being more severe. Anyway, while the wheels we're off. I thought sod it, I might as well tighten the bearings as tight as possible before they bind too much. And see if the same happens... and it did! So it's 100% not a hub bearing issue now. There was no play before I adjusted them, but I thought I'd give it ago incase. Is the only thing it can be now is the brake flexis? I'm very very reluctant to replace more parts and have to bleed brakes again with what I've already done. If it is the flexis, does anyone know who custom makes them in the rubber variety instead of stainless? Thank you

Thanks Ralph. Is there anyway I could pin point it do you think? I mean I've tried turning on the spot and making the issue happen, and I couldn't see any issues underneath on lock to lock. But I'm keen to isolate it if I can. Braided hoses are a pain as they can't be clamped.

***UPDATE*** Hi all. New servo fitted this evening. And WOW! The brakes are incredible!! in fact that good I was a little dangerous for the first few miles on the test drive, as I was so used to pressing hard and now so little effort is needed it was locking up every time even on dry roads. The pedal also sinks on start up every time. And the brake pedal seems to feel great so far. It's a bit inconsistent at times, mainly due to the increased travel when cornering I believe. But overall a fantastic result so thanks to you all

Tried removing the reservoir cap, and took it for a drive. No difference unfortunately. New servo arriving today, should be able to fit tomorrow. I'll update with my findings and hopefully improvements in that department. Thanks everyone

Thanks Pawl12 and western. I had a rear hose from Dave at llama Ralph, great service from him. He's local to me. Pawl, the brake pads are barely worn really. Although I'm still going to try what you suggested. Somehow I'm really banking on the servo causing the pedals increased travel as I have read some very weird faults from inferior servos. It's doubtful though.

Now that's very interesting. I will try that tomorrow evening as it sounds quite promising. Do you recommend removing the reservoir cap fully? Or slacken it and leave it on a couple of threads? It did always make me wonder if it would have happened with old calipers and rusty pistons, so your logic sounds promising. Thanks a lot

They were terrafirma Ralph. I regret changing to braided flexis really, as with the rubber ones it'd easier to diagnose problems.

I'm processing a warranty claim on the servo, I've just had to buy a new one to be refunded the faulty one. And thanks Pawl12. I'll certainly give it ago removing the reservoir cap,I have nothing to lose. Although I still can't get my head round why that would only work when the steering is turned?

Thank you both. Managed to test my dad's vacuum pump this evening, his also drops the vacuum when turned off, so it seems exactly what you said pat_pending. I've finally proved the servo is faulty, again my apologies for it being a long winded one. It just not expected with new parts from good manufacturers, but maybe that's the world we live in now. As for the brake pedal travel increasing when turning, I'm fantasising the new servo may also cure that. But I highly doubt it, every suggestion has now been tried. Thank you all who posted

Have you tried a good quality air or cordless impact gun?

Cheers for that Ralph. Should the vacuum pump hold vacuum though? Like my mates td5 and 200tdi does. My vacuum pump just drops off when the vehicle is turned off, the other engines don't.

Hi All. Sorry to bring this one back up, but ive been doing some testing, and getting closer to the one problem, or maybe both. Firstly, i purchased a vacuum gauge and tested the vacuum the pump produced at tickover (apologies if this isnt the correct teminology to follow): -my 300tdi: 24 inches mercury with a warm engine, 23 with a cold engine (seems odd that this differs between days? Beleive it could be temperature though?) -A friends 200tdi: 24 inches mercury with a cold engine -A 2002 td5 defender: 25 inches mercury cold engine -My dads 300tdi: Very low reading of about 18 inches mercury One thing i did notice, was the 200tdi and td5 engine held the vacuum on the gauge as soon as the engine was switched off and remained at that pressure for a while, where as my 300tdi loses the vacuum. Im yet to try my dads as i forgot, but his pump is seeming worn compared to my new one. Next test i did was on my servo with a mityvac which produces a vacuum, using the connection into the servo acting like a vacuum pump. I tried producing a vacuum on my servo, and had absolutly no luck at all, couldnt get the mityvac to budge off zero. I then tried my friends 200tdi and td5 defender, and managed to get almost maximum vacuum reading on the gauge despite it being hard. I removed my vacuum pipe from pump to servo and pressure tested it, no leaks or issues at all. So its clear i have a servo leak so that will be replaced (hopefully under warranty). My question i have is, should my vacuum pump hold pressure as soon as the engine is switched off? like the 200tdi and td5... or doesnt it matter when the one way valve is working correctly in the servo? Thankyou all and sorry its been long winded.

Cheers Bowie. My dad has virtually the same vehicle as me,so I was thinking of getting a vacuum gauge and comparing the readings to mine. A friend has a 200tdi and td5 defender too,so I can get some figures of what it should be. I know for certain that the one I removed wasn't providing as much vacuum as this one. But that pump I removed was also inconsistent, sometimes brakes very just about ok, sometimes it felt like new servo assistance at all. Henc e me replacing it

I changed it about 3/4 months for a bearmach part, it did have a sticker on it called briturk though. Which didn't give me much confidence. Cheers Pete

Cheers Ralph. I'll look into that. If the good brakes aren't sustained. I will invest in one of those and find out if the vacuum pump in intermittent. Despite being new! It was only a "briturk" branded bearmach pump

All i did was pull the vacuum pipe off the servo, nothing more. All i can think of is possibly caused seals or pistons ( I have no idea) to seal better in the vacuum pump, and its providing more vacuum/suction. I couldnt have disturbed anything else. Is there a gauge of some sort i can test the vacuum pressure?

Deep i really appreciate that in depth reply, thankyou very much. The weekend im going to work my way through all those checks youve suggested one by one. Thankyou to you all for your in puts and advice, eightpot ive replaced the rear flexi twice with no luck unfortunatley, i had similar thinking to you. This week as you all know ive been inspecting the land rover, doing tests here and there to try and get to the bottom of the two problems. Well after a few of you told me to double check the servo and vacuum pump (inc pipe) i did just that on Tuesday evening. I started the land rover, and listened for any leaks around the servo and as i thought, absolutley nothing. So then i removed the pipe and valve from the servo and put my finger over the end of the sucking vacuum pump and held it there. My thoughts behind this were, if i blocked the one end and the pipe was leaking, i would feel the pump sucking further down the pipe (at a join, crack etc).... As i suspected the pipe was fine, and so was the one way valve. Refitted the pipe to the servo, checked for leaks and left it at that. *** Something odd happened today***.... Came to use the land rover this morning... WOW the brakes were fantastic!!! Better than theyve ever been, and i couldnt fault them. I thought thats strange, they are sometimes inconsistent but not to an extent like this improvement. Drove it again this afternoon, and exactly the same, the brakes were amazing. Even the pedal sinks on start up (for the few times ive tested it) and when the engine is off, it takes 4 to 5 pedal presses to exhaust the vacuum. Locking up the wheels is so much easier, and the pedal feels more 'car like'. Braking efficiency has double by how it feels. When i got back, i thought id check the rear brakes too, and you wouldnt beleive it, perfectly polished like a good braking system should look. It almost looks like ive fitted new discs. So why??!! Has putting my thumb over the pump for too long done me a favour? Because i certainly havent done anything else to it. And the one way valve was sealed perfectly before and after i messed. The pedal travel still increases on cornering, but when the brakes are this good, it doesnt seem to matter as much!

Cheers Bowie. I've been clutching at straws for some time, any suggestion I very appreciated. Where should I look exactly? Just around the pedal box mounting holes to the bulkhead? And inspect the pedal box itself?

I has similar Scott on nsf bearing. Was convinced it was the problem but nope. Thanks for clearing that up though, I won't bother with the td5 approach

Thanks bowie. Unfortunately I've checked and changed all four hub bearings. I've thrown so much money at the brakes and axles each time left with dissapointment. Thanks to everyone for your input, one day I will find the reasons why I have very strange faults. It's probably the reason why I have several invoices for the vehicle stating "fix poor brake efficiency" over the years

Thanks Ralph. I'll try and give that a go tomorrow then and dig the old servo out. I could even pull the pipe of dad's 300tdi and see how it works on his too. Just a thought to rule out wheel bearing adjustment, after browsing the land rover pages tonight. Would it be worth fitting the td5 spacer between the wheel bearings and really torquing them up tight. Just to really rule out the bearings? Or would that be a waste of time? I'm convinced it's not them though, how many times I've checked them now I've lost count. But you I spose you never know with these land rovers.

Thanks for the reply. That's exactly what I thought. That's why I replaced 3 stub axles, front two have been replaced. Very much doubt it's the rear drivers side that is remaining. It would occur while driving straight if it wasn't wouldn't it?

Sorry for a stupid question Ralph. But could the one I took off be tested with just connecting the vacuum pipe with the engine running. To see how long it holds the vacuum? Or has it got to be fitted to he pedal box.

Thanks Ralph. So the only area it can leak it's around the joint? According Google and YouTube they do duck in air on the pedal box side when the brake pedal us pressed. Would you all agree it sounds like a faulty servo for one? And another issue with the pedal travel increasing when turning then?

So providing the vacuum pump is working correctly, the pipe and the one way valve isn't leaking... The only thing that can leak is the servo itself? The joint at rear of the servo (pedal box side) can't leak, and neither should the joint the front side (master cylinder side). If that's the case, it sounds like I have a faulty servo, and another issue.