Crate gx130c chorus

[hene07]

Anyone know how to fix a crate gx130cs chorus? I've reclamped the power terminals and changed the mn3007 and 3101 yet when I turn on the chorus nothing happens except my right speaker doesn't work. If the chorus is on there is no chorus effect it just turns my 4x12 into a 2x12. Any help?

 

[Jon Snell]

I would put the original chips back as any replacements are usually fakes, especially if from fleabay or other iffy sites. They have not been manufactured for many years.
With your service manual, follow the schematic.
Check the oscillator is running before anything else; TP13


Edit; more info added.