ZF Services UK recommends two vital checks when replacing a concentric slave cylinder on the Renault Clio.
First, carefully compare the diameter of the hydraulic connection on the new CSC with that on the removed component. Renault uses more than one connector size (e.g. 11.7mm or 13.3mm) on CSCs with otherwise identical dimensions, and sourcing the correct part using the VIN alone is not always reliable. Fitting the wrong part can lead to fluid leakage and clutch operating problems.
Also check that the system is replenished with the correct fluid after fitting – Renault uses brake fluid for some applications and mineral oil for others. If mineral oil is mistakenly used on a brake fluid application, the CSC’s inner seals will swell, allowing fluid bypass and causing leakage. Mineral oil applications generally use a CSC that is green in colour or includes a green plastic section.