Thread: Brakes Hot NO Pedal

Thats the only thing i haven't replaced, will order 2 new lines

Originally Posted by DEFENDERZOOK

what he said.....if the piston is stuck down....it will displace the fluid that it should be pushing.....
hence the higher level in the reservoir.......

masters can leak internally past the first seal and not leak out the back.....
doesnt happen very often......but its not unheard of......


as for the check valve.....my brain isnt switched on at the moment so i cant picture the circuit it will allow fluid to flow through......
may also be a possibilty........

either way...it all points to the master cylinder......and having recently changed the brake fluid
may have caused the problem as the piston and seal gets pushed beyond its normal working zone.......
and into any crud that may be building up....which could have damaged the seal....and it finally gave way when it was worked
hard coming down the steep hill.......

methinks.....

I have had this problem with a hilux.
No leakage past the rearward seal but the secondary piston valve seals allowed the fluid to circulate without doing anything.

cheers

Originally Posted by Vern

old thread i know, but Tank, what was the outcome?
I'm having the same trouble, except pedal not to the floor, just no brakes, this has happened 4 times in as many years on steep decents (all coming down from mt Hotham and Dargo. I.ve replaced, pads, rotors, fluid, 1 caliper, booster, over the last couple of years.
Brakes don't get smoking hot, only a slight hot brake smell
let it cool down and all is good again

(D1 auto)

Vern/Damien and others, how time flys this problem was solved and posted back then, I haven't gone back to find it though.
What happened was that there was water and other contaminents in the brake fluid, I drained and replaced the fluid twice and both times I was getting clean fluid through the bleed nipples. This did not work and it was very scary in an Auto down a slope you couldn't walk down or up because the Auto will not go back into first low if the revs are too high, which they tend to be when you have no brakes, thank christ for the Eco drains across the tracks.
Well as a last resort I decided to Read The ****ing Manual (RTFM), genuine Land Rover 93 Disco Workshop Manual and there it was. As you would know they have 4 piston Calipers and a Dual Brake system.
From under the Disco the 2 front calipers have 2 bleed nipples on the inside (engine side), but until I RTFM I didn't realise that there is another bleed nipple at the top of the caliper on the outside of the caliper, which you cannot see with the front wheels on. So I had been bleeding this system and NOT bleeding the top outside nipple, which held a whole heap of very very contaminated black crap that was supposed to be brake fluid, NOT dirty water, about 250ml of it.
So I pulled the calipers and cleaned thoroughly, replaced the seals, put it back together, drained all of the recent brake fluid and filled with nice new fluid and bled all "8" (6F 2R) bleed nipples and haven't had a problem since.
The 94 Disco I have now only has 2 bleed nipples on the front calipers on the inside, no nipple on the outside.
The crap that came out of the outside nipple on the top of the caliper was probably there forever, as no-one I asked knew there was a bleed nipple on the outside, BTW there were blue rubber caps over the outside nipples and they had melted and run down the caliper, so that was the problem solved.
if you are having a similar brake problem, drop your front wheel off and see if there is a bleed nipple hiding there, the W/Shop Manual describes the method of bleeding these type cylinders, if no manual let me know and I will post method, thanks to all who offered advice, much obliged, Regards Frank.

frank, mines (wifey's) a 96 so single circuit, going to order new lines tomorrow, will pump 2l of fluid through just to be sure. If that doesn't work, then sell it, wifey's lost faith

Not Landy but this happened to a mates SWB Patrol.

Brakes fine on road even with a braked caravan in tow.
How ever when on steep off road decents the brake pedal wouldn't hold.
Pedal sunk to the floor while the fluid level incresed.
Worn seals in the master cyl which got changed with pads and rotors.

Originally Posted by Vern

frank, mines (wifey's) a 96 so single circuit, going to order new lines tomorrow, will pump 2l of fluid through just to be sure. If that doesn't work, then sell it, wifey's lost faith

Damien, have you dropped a front wheel and checked, won't hurt.
If not take it to a brake specialist, not your local mechanic or tyre place, but to a specialist and have them bleed the brakes for you, won't cost much and at least you may find the problem, Regards Frank.