What color is your Part C dev before mixing? If it is dark in color / purplish or even black, then it has gone bad and should probably be replaced.

I learned this the hard way a few weeks ago with the Rollei kit (which is supposedly assembled using Fuji-Hunt chemistry). I will say that I got decent enough results from the 5L Fuji-Hunt kit even after the Part C had turned dark, but will not attempt that again after I ruined some rolls a few weeks back with a bad Part C from the Rollei kit.