Had a rather sudden and 'different' failure of slave cylinder on '84 Mazda. It suddenly went out w/ no particular warning but what is strange is how 'gray' the fluid had suddenly turned. I probably glance at it once a month and it had been it's usual honey color so this was relatively sudden.
I pulled the slave and it appears the cylinder had somehow started to slide at an angle against the actuator pin - this caused the (alum) cylinder in teh bore to rub against the cast iron walls of the cylinder itself. I presume the alum filings turned the entire hydraulic fluid gray - my guess anyway.
I'll put a new cylinder in and flush out the system but am wondering about the M/C. Remember that gray stuff got throughout the the hydraulics. And looking on the back side of the clutch pedal at the M/C it looks like a small dab of gray slime is there too. I'm wondering if the presence of the alum filings has caused the M/C to start leaking a little but a simple cleaning and flushing would restore it...?
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Also how realistic is it to 'rebuild' these w/ kits vs buying new (expensive) or rebuilt slave or master cylinders. I get the feeling nowadays that most times folks just replace w/ new or rebuilt rather than mess w/ rebuilding...?