Not much chance of getting help unless you tell us exactly what you are trying to fix. OK, its a long case clock. Is it an antique mechanical one - weights that get wound up? Is it a modern mechanical one? Is it one of those God-awful electronic ones with a tiny movement up top, a loudspeaker for the chime and a big mostly empty case all for show?
Make? Model? Accurate and meaningful description?
acp, May 2017