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Concentric Slave Cylinder Contamination Issue Solution

The Nissan designed Concentric Slave Cylinder for 370Z's has proven problematic, with clutch dust contamination and resulting seal issues. The factory Concentric Slave Cylinders (CSCs) are known to fail prematurely on late model Z-Cars with HR motors. While Nissan has modified the original design several times, they were never quite able to solve the issue. Over the years, some have simply removed the entire concentric system and replaced it with a traditional style, externally mounted slave cylinder. Custom designed kits such as these are effective; however, they require specialized components that may not be easy to source in the event of issues down the road. A small number of manufacturers worked to create suitable replacements for the original that solve the design flaws, such as Jim Wolf Technologies. The symptom of a bad CSC is a pedal that can be pressed to the floor and doesn't return, which is a sign that dust from regular clutch wear has made it all the way past the hydraulic seal of the CSC, causing the seal itself to lift. This allows fluid to spill out into the bell housing (and onto the clutch) and clutch dust to make its way further through the clutch hydraulic system (there have been cases where dust made it all the way into the reservoir!). Once the dust reaches this point, the entire hydraulic system needs to be fully flushed, any rubber components should be replaced, and all metal tubes should be fully blown out, prior to the installation of any replacement.