If you bleed the system, and it works fine. Then it gets soft and spongy, so you
bleed it again, and you get air out, it means that air is leaking INTO the system.
There is no sign of fluid leakage/loss of fluid (did you check for any fluid on the
carpet under the clutch pedal ?). So where does air get in that fluid can't get out ??
About the only place I can think of would be thru the slave cylinder piston seals.
There are (should be) two seals on the piston. One designed to keep the fluid in,
and one designed to keep air/water/crud out. If the seal nearest the outside air
was accidentally installed the wrong way round, there is a chance that air could
get drawn in if the fluid pressure went negative.
I don't actually know if it goes negative (below atmospheric), but I guess it could
happen when you release the clutch. Other than that, I'm out of ideas So if
nothing else helps, it might be worth taking the slave apart and checking the seals.
jondee86 has been a member for 735,126 days.
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