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| Johan_B Member Since: 20 Sep 2024 Location: Gothenburg Posts: 165   
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If the piston seals are old and worn I guess it is possible that your emergency brake caused them to give up. I had it happen on one caliper this winter, also in an emergency brake.
Either new calipers or rebuild the ones you have. I got new calipers since I didn't have the skills/tools/time to rebuild them. If your pedal is soft and you don't have stopping power you should not drive it until sorted. |
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21st Oct 2025 12:13pm |
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| TexasRover Member Since: 24 Nov 2022 Location: Paris Posts: 1366  
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As one gets older and have been exposed to more and more older vehicles, some in longish ownership, you realise that some things keep popping up as needing replacement over time. Typically and convently these are the things that stay longest available for older cars. Brake calipers are right up there.
Rebuilding very doable and fun, but straight out replacements are cheap, readily available and more convenient if you are short of dry workspace and time. For all four a rebuild might justify the effort as there will be saving to be had. |
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21st Oct 2025 1:34pm |
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| I Like Old Skool Member Since: 23 Feb 2015 Location: Manchester Posts: 886  
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Highly unlikely to have popped all 4 calipers at once, better chance of winning the lottery. I suspect any dampness you are seeing at the wheels is probably existing axle oil leaks from failing hub seals, especially as you say the brake fluid reservoir is still at level.
Might be a Flexi hose that is ballooning, need a second person to press the pedal while you inspect for this. Also, does the pedal sink if you keep your foot on it (hence, a leak or passing seal in master cylinder). Could also be the brake servo has cracked so you are not getting the vacuum assistance you are used to. If you are unsure what you are doing/looking for then brake repairs are one thing I always suggest are left to an expert. No room for error or learning on brake repairs and the consequences of getting it wrong can be much, much worse than leaving you stranded at the road side. |
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21st Oct 2025 5:21pm |
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| anotherrick Member Since: 02 Feb 2024 Location: Lancashire Posts: 40  
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Thanks for the above replies guys. Left the defender at work last night and used work car to get home n back in this morning.
Had a look underneath earlier and can't see anything obvious. The brake pedal has full travel with no resistance with or without the engine running. Cant "pump it up" Fluid level remains the same. If I drive forwards/backwards around 5mph the brakes work (vaguely) but the pedal is fully depressed. Obviously haven't driven any faster than that. So that's where im at. |
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22nd Oct 2025 3:40pm |
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| Mdm Member Since: 11 Sep 2013 Location: Sunny Lancashire Posts: 1696
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recovery time to a workshop for some tlc now
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22nd Oct 2025 3:51pm |
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| anotherrick Member Since: 02 Feb 2024 Location: Lancashire Posts: 40
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Yeh, can't move it till the weekend. Will need to check with my breakdown cover if they'll take it to a garage of my choice rather than their preferred or nearest.
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22nd Oct 2025 4:28pm |
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| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 18038 
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I suspect a master cylinder fault from what you've described. No pedal pressure with no loss of fluid suggest MC seals have failed. Hopefully not an expensive repair.
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22nd Oct 2025 5:06pm |
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| Dinnu Member Since: 24 Dec 2019 Location: Lija Posts: 3649  
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As Blackwolf mentioned, the master cylinder non return valve seal has possibly failed, letting the fluid back into the reservoir. I had similar, if coming to a slow stop, the pedal would start creeping down. Was not a problem in a hard stop. 1988 90 Hard Top, 19J Diesel Turbo, Shire Blue - Restoration ongoing
2012 90 CSW, 2.2TDCI, Santorini Black |
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22nd Oct 2025 8:46pm |
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| anotherrick Member Since: 02 Feb 2024 Location: Lancashire Posts: 40
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Had a final look today with the help of a colleague pressing the brake pedal. This time the leak was very apparent. The brake line that runs down the inside of the chassis had corroded towards the back end where one of the fasteners is.
Priced up the genuine part and it's expensive for what it is so probably going to make my own. Anyway thanks again for the replies. Hopefully they'll be helpful for other people with similar issues. |
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24th Oct 2025 1:16am |
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| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 18038
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Aha, so the fluid level was going down, contrary to earlier reports!
That makes more sense, the most likely failure under heavy braking is a corroded hard line, closely followed by a deteriorated hose. That corroded hard line should have been picked up on an MoT, it won't have corroded enough to burst that quickly. |
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24th Oct 2025 10:06am |
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| anotherrick Member Since: 02 Feb 2024 Location: Lancashire Posts: 40
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Yeh my colleague was pumping the pedal like they were trying to stamp out a fire haha hence the more noticeable fluid loss.
I did have an advisory on the last mot saying brake lines covered in grease/other material. |
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24th Oct 2025 11:13am |
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| custom90 Member Since: 21 Jan 2010 Location: South West, England. Posts: 21029
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I keep the brake lines on mine coated in a light spray of Dinitrol. (Not on flexi).
That just leaves a layer of extra protection. Or you can just use a light paint of Matt or gloss black, but the above is better for corrosion resistance and longevity, obviously only a light coat, not thick. Just one leak will do it, but some vehicles have a brake bias valve so that there is always front or rear brakes always retained in case of a failure. Does your year have one? TDi’s possibly didn’t have those? ____\We|Will|Win/___ ____/🇬🇧🇺🇸\____ _//*⛽️🛢️⚙️🧰*\\_ |
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24th Oct 2025 6:59pm |
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| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 18038
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That's not what the bias or proportioning valve does, it merely adjusts the rear brake line pressure according to load conditions. The protection from a burst pipe causing total loss of brakes is provided by the dual circuit master cylinder and separate brake circuits for the front and rear brakes. On an ABS vehicle.there are four circuits from the ABS modulator to the wheels, one for each, and dual circuits from the master cylinder to the modulator. I am not sure whether the modulator can protect against single line failure though, so it may be that functionally even an ABS vehicle is just dual circuit (certainly the Disco2 is functionally dual).
If you do lose one circuit on a dual circuit vehicle brake pedal travel will increase dramatically and disturbingly since the travel lost in the leaking chamber in the master cylinder has to be taken up. It is quite exciting when it happens! |
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24th Oct 2025 9:15pm |
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| custom90 Member Since: 21 Jan 2010 Location: South West, England. Posts: 21029
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Very articulately explained BW, these things are always good to learn.
I think you may get away with coming to a halt, but I think you’d soon know, as you say the extra pedal travel would be a very significant sign. And quite alarming too! Beyond that it’d need immediate attention, fluid loss alone is one factor that would happen at a fairly rapid rate even with a single line leak. Mines non ABS, non TC as well, to be honest I’m glad as those things can cause more trouble than they are worth imo so there is less to go wrong. Great when working but, extra problematic when not. I know that with ABS systems you can use a slightly higher pressure bleed process up to a certain amount a little more than say 8 - 10psi approx for pressure bleed for non ABS. ____\We|Will|Win/___ ____/🇬🇧🇺🇸\____ _//*⛽️🛢️⚙️🧰*\\_ |
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24th Oct 2025 10:10pm |
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