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went to do some bits on my 323 today and my brake fluid is down to the bottom of the
resevoir.ive checked all the pipes and every caliper and got someone to pump the pedal but i cannot find
a leak anywhere? anyone got any ideas

Tank leaking due to a bad connection to the brake master? Otherwise, and this is most likely, the master is leaking into the brake booster showing no leaks anywhere... new master or overhaul required.

thanks jeroen ill get it looked at the tank is fine and the connections are good so this must be it

Check that the slave cylinder is not leaking, it usually drips down from the gear box bell housing if thats shot.
Also check under the front carpets. My master cylinder was leaking down into the drivers footwell and i knew nothing about it as it went underneath the soundproofing and carpet.

the pick up for the clutch is abt halfway the tank to prevent you from running out of brakes because of a leaking clutch system. So if the tank is really empty it can't be (just) the clutch.

mines an auto too so i think the master leaking into the booster sounds most likely

im going to take the master off in a couple of days and see whats wrong.
what do i do about the fluid thats leaked into the booster?
can i just empty it out if so is it just a case of taking it off the car and tipping it out?
will the booster be ok or will it be damaged?

check brake pressure regulator, in my case i have leaking there.

I had the same problem and indeed it leaked into the booster. I emptied it en cleaned the inside with washing petrol to make sure it would not get rusted.

mine was a leaking master cylinder.got a service kit from big red for £19 now all is good