Did you bleed the clutch after installing the slave????

Just putting fluid in the slave and installing will not bleed the system.

99 to 1 there is an air pocket in the system. You will need to reverse bleed the clutch by connecting the clutch bleed screw to the brake caliper bleed screw then pump the brake peddle...and wait for the air bubbles to stop.

There is also a possibility the hose going from the reservoir to the master clutch cylinder is bad.

Pictorial here

Got a 1980 240D today.....

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