J-Man

Hello, newbie here... recently picked up a used Hammond SK1-73, it's seen better days, but still lovely. got a major issue, that I'm hoping someone can help me with. AS I run through the presets, the only ones working are organ presets. No strings, no Horns, no piano, just reeds.. I'm wondering if this con be corrected internally or whether this requires extensive repairs. Any assistance is welcome. thanks J-Man