Leaking Master??

[Not Happy Jan]

Good Morning. Happy Australia Day.
My reservoir on the clutch keeps going done. I cant find any leak anywhere. Nothing on the firewall. Nothing on the fittings either on the master or the slave cylinder. and slave cylinder is dry??  I didn't know brake fluid could evaporate.

[ardiesse]

Brake fluid does evaporate, but very slowly at room temperature.  Instead -

Unbolt the mater cylinder from the firewall and move it forward just enough so you can get your finger in behind and wipe the rear of the master cylinder.  Are there any traces of brake fluid on your finger?

Get under the car, unhook the rubber boot from the slave cylinder body, and look inside the boot.  Is it wet?

"Yes" to either means the cylinder in question is leaking.

Rob

[Harv]

Grace's ute had a similar problem. It used to leak inside the car (along the pushrod) and dribble onto the floormat. A stainless liner in the cylinder fixed it.

Cheers,
Harv

[Not Happy Jan]

Nothing anywhere???
WTF

[Harv]

Does it drop any fluid if parked for a week or so on clean concrete (or concrete with newspaper taped down to make a clean surface)?

Have you accidently mistraced the lines, and it's really the brake master cylinder which is losing level (I've done that before  ).

Cheers,
Harv

[Not Happy Jan]

  No Harv... but i wouldn't put it past me.
It has an oil leak but no other ones

[DougT]

Have you checked to make sure the slave cylinder push rod adjusting nut lock nut is tight and not allowing the adjusting nut to unscrew thereby lengthening the slave cylinder piston travel which would reduce the fluid level in the reservoir? Just a thought. Doug