It is recommended to check the fluid level in the expansion tank every 4 weeks.
Top up with SAE J 1703, DOT 3, or DOT 4 brake fluid when the fluid level drops.
The fluid level in the expansion tank must be between the MIN and MAX marks. If the level has fallen below the MIN·mark, the hydraulic clutch should be checked for leaks. If necessary, replace the relevant parts. If the system is tight, then there is wear on the clutch disc.