If the baskets are loose, then they aren't quite seated properly, and you can't clamp down the top unless the baskets are firmly seated. If the top is loose at all, air will get into the system and it will go dry.
If there's any water in the canister when you try to restart, the primer won't prime properly. Make sure to empty the canister before you try to restart.
I've had two occasions where I needed to restart. In both cases I restarted the primer by putting water in the intake tube through the little funnel. After you've filled the intake tube with water - don't forget to remove the funnel and screw the top back onto the tube!


