I'm just finishing a total restore of my ES. Prior to the restore all flippers were working properly. I have everything put back together with the playfield on a rotisserie. During my testing I noticed that the upper left flipper has the expected strength; however, the lower left flipper is weak. The strength of the right flipper is fine. The lower left flipper is strong enough to just barely make the center ramp shot. Any suggestions to resolve my weak flipper problem would be greatly appreciated.