Just started getting problems with this. I disassembled the clutch looking for some wearable material that was obviously worn down. It appears that it's all metal to metal materials. Looking at parts drawing there is a "Driven Disk" part 75151-VE0-000. Should this disk have some wearable material on it? Would replacing this disk fix the problem or do all these parts need replacing? Mower is getting old but still runs great. Debating whether to repair or just buy a new mower.