Ego 06 leaking and dropping balls

[odons]

Hey, i just bought a used ego 06 and as soon as i put the tank in and power it up the bolt is loose and air is leaking from that area. once i shoot dry once the bolt locks in and leaking stops, then when i start shooting i get about ten shots straight then another 5 completely drop to the ground, one works and five fall and this keeps happening, and suggestions?? I heard the solenoid is bust but i really hope that isn't the problem.