Gato_Solo
Out-freaking-standing OTC member
It stops itself automatically. I can't adjust the time it spends sucking... it's supposed to do that automatically. It makes a noise while it's sucking, then the noise gets audibly higher-pitched, sort of like how fan blades spin a lot faster if you cut off the air source, and after a second or so of that it seals it off.
Sounds like its not sealing properly, then. First, check the heating element for the sealer. If there's any plastic stuck to it...and I mean any, that would keep it from sealing well. If that's not the problem, then you have only one more option. Double seal, and see if that works...