hey everyone, just got my first rover a 1997 disco 1 with a 4.0 stroked to a 4.6. Anyway i am absolutely stumped on this current problem i seemed to have caused. i got home from work and after parking the rover went straight into replacing the brake master cylinder. ive replaced many before and it was a textbook job. although when i went to power bleed the brakes this little port right behind the reservoir was gushing fluid when i pressurized the system with my schwaben power bleeder. i still went through with the bleed knowing the new master must be a failed unit. i go to start it afterwards and it primed like normal, turn the key no crank just spastic light flashes and clicks and then full electronic power loss. i hooked a jump pack to the battery and same thing again except now the alarm is blaring. i removed the battery and called it a night but i gotta say what the **** did me replcing the brake master cylinder have to do with the alarm locking me out? i did try to start it with the hood open if maybe that means anything? also i noticed i got a non abs master when i originally had an abs unit? could that be the cause?. im at an absolute loss and will be going back out tomorrow morning to investigate further. attached are pictures showing where the brake fluid was gushing when the system was pressurized( circled in red) as well as my old unit for reference. could the fluid level sensor have caused the no start/ alarm lockout too? any help is greatly appreciated!

new master installed

leaking “port” after pressurizing the system to 15 psi from the cap with power bleeder

original master

a pic of the disco

 

Also want to add i successfully reset the alarm and got the truck to prime again like normal but then the exact same thing happened! my key fob also stopped working after this ordeal as well!

will most likely try to start it with the hood down after resetting the alarm again, then if no luck might try putting the old master cylinder back in or at least using the old brake fluid level sensor to rule that out. have the battery hooked up to a tender tonight as well as i know low voltage has caused some weird electrical things to happen on these vehicles

 

well i solved the alarm lockout by one of two things i did. i removed the battery and let it fully charge over night on a tender even though it was functioning fine the day of. shen i installed the battery today i closed the hood and all doors. used my fob to lock and unlock the truck 10 times, got inside and closed the door and then manually operated the locks another 10 times. finally with the doors unlocked and closed i gave her a crank and she started right up. now just to tackle the brand new euro spare master cylinder that was leaking fluid during the bleeding procedure. even after the bleed the brakes are soft but suprisingly operating the brake pedal doesnt cause it to leak fluid even with the truck running and the assist of the brake booster. strange might throw the wheels on and give it a short drive, if the brakes suck i guess ill order a different brake master cylinder and attempt to get my money back on this one

 

great work buddy keep it up

 

to finish this thread off i want to post my resolution to the brake master situation. i found the euro spare master cyl to be junk, reinstalled my factory one only after replacing the resovoir, cap, sensor, and most importantly resovoir seals from the euro spare master cyl onto my stocker. my original seals where destroyed and my cap seal was as well! after assembling everything i pressurize my brake system to 1.5 bar with my power bleeder and what do you know shes holding pressure no prob. finish the bleed and do a test drive, brakes still spongy. back to step one. i notice pumping the brakes barely has an effect on stopping power. so i check my vacuum lines to my booster and the vacuum line is almost completely slid to the end of the fitting. snug that up and give a quick test drive to find my braking performance is what i would call good nuff. miles better than before but still nothing like my performance cars lol. can just about lock up my 33” mud tires on pavement so id say not bad.

 

I have had problems with any Master cylinder except a factory Land Rover one.