Yep it's normal I would say. Don't really know what you could do to stop it, but I think it the motor were ran up to 190* or so before shutting off to store it would boil away any condensed water that was in there. Warm garages and high humidity create this sort of thing. Don't think the dessicant bags are going to help, that water isn't just on the valvetrain it's pretty much all through the motor. Very dry here in the desert, maybe other guys on here can offer better advice. :? 8) JB