Saturn reading disc problem help please

Hello everybody, i am a guy from Bulgaria and recently have bought a model 2 Saturn from ebay. But there is a little (or not so) problem- the disc reads normally only at the beginning, when i try to skip to 5th-6th or next tracks (audio cd) there is strange noise from the console and eventually the disc stop spinning. I've opened the console and after some "researching" i found that the laser assembly is a little bit far from the gear that moves it forwards and backwards, i don't know if there should be something that keeps them close but obviously at the moment the gear can't move the laser... I tried playing the disc with the Saturn laid down on its right side and everything works normally. So please somebody help me, any suggestions are welcome. I've made a picture in paint just to show what i am talking about (don't laugh much :D ).