Hello Marshal, some additional information to help us help you:
Is the noise only noticable when you are loading coal, when the cover is off the coal hopper???
Did you try emptying the hopper completely, and look at the feeder to see if there is a large piece of coal or piece of rock causing the noise..
How frequent is the 'ticking' once every second, more frequent like from a motor? or less frequent??
Can you 'touch' the hopper, or the feed mechanism and 'feel' the noise??
I'd bet on a piece of rock or large coal being hit by the feeder bar. But I'm really just guessing..