Noisy Gear Engagement, Vehicle Stationary

NOISE FROM CLUTCH OR GEARBOX IN NEUTRAL, WHICH DISAPPEARS WHEN CLUTCH IS DEPRESSED
Suspect gearbox input/primary shaft bearings, refer to the "Clutch Noise, Mechanical Faults". Testing and Inspection

NOISE FROM CLUTCH OR GEARBOX IN NEUTRAL, WHICH CHANGES TONE OR BECOMES WORSE WHEN THE CLUTCH IS DEPRESSED
Suspect worn release bearing.

KNOCKING/RATTLING FROM CLUTCH OR GEARBOX IN NEUTRAL, WHICH IS REDUCED OR DISAPPEARS WHEN THE CLUTCH IS DEPRESSED
Suspect worn/weak release lever retainer or clutch unit.