the pedal free travel is adjusted from within the master cylinder pedal box , but i guess you know this .
check that the nuts havent come loose , i know they are a swine to get at unless you have slim cranked spanners.
it may well be youre slave cylinder at fault , i know my LR90 has done similar things to yours before the cylinder has gone , but normally this goes hand in hand with some fluid loss ..
check if you pump the clutch pedal that the slack reduces back to normal .
the fluid level may not drop by much at all but one of the piston rubbers may be perished .
failing that its something to do with the clutch release bearing or the clutch cover , but unless you lose it all totally i wouldnt worry too much about slight changes in pedal slackness .
check the flexible hose also .
it is probably best to change the slave cylinder first and then the master .
if you have the LT77 gearbox and exhaust pipe going near the slave cylinder then this is sure sign for slave cyl problems , they suffer premature, or low service life because of the heat generated in this area . normally with slave cylinder problems you do "lose" the clutch pedal operation totally once or twice before the cylinder eventually goes , you can recover it possibly by pumping clutch pedal but it will fail completely at some stage . mind you fluid loss will also occur at this stage but you wont see fluid leaking because it has a tendency to go into the bellhousing .
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