Bit of a puzzler , ,had a morning buzzing round Sheffield last week after numerous calls ,stops, gear selection became awkward I noticed that the clutch pedal felt strangly floppy pumped it a couple of times every thing back to normal went home went out yesterday 30 miles or so started again stopped checked fluid ,level ok pumped pedal back to normal , along time ago had some thing similar with a 2 litre Marcos traced it to clutch pipe to slave from master too close to exhaust manifold warming fluid up making bubbles bleed out back to normal , rerouted pipe and heat shielded it no more probs . theclutch pipe on the mx 5 goes nowhere near the exhaust so sort of rules that out any one got any ideas please car is 1992 import with 250 ,000+k on it replace master ,replace both master and slave ? other than this drives perfectly Clues eagerly awaited thanks mick
The clutch slave cylinder seems to be a common failure point after a few years.
You can check by pulling the rubber gaiter back on the slave cylinder to see if it’s leaking, if fluid is found there’s your problem.
I had a very similar problem with my Mk2.5 at 87000 miles. No fluid loss, but no clutch pressure. Turned out to be the seal in the master cylinder. Rather than faff about, changed the master cylinder and the problem was solved.
Would go with slave cylinder replacement, not much dosh compared to the master cylinder.
If however your clutch is on its last legs the pump up on the pedal would give the same result if its not already slipping. That will happen shortly if the slave cylinder piston is having to move beyond its normal travel due to friction disk wear. A bit like brake disks and pads, It all works but feels spongy cos its on the limit.
You`v probably had your monies worth out of the clutch.
Good luck with it.