I have the same problem...leaks when I refill, and then again when the fluid level gets to about the wick windows. I've had my BB over 2 months, and no probs with cartos other than a little condensation.
Also, it seems to be running quite hot for the 2.2ohm/4.0V I'm running. Juice get dark quite fast, and the BB is quite warm on the backside behind the tank...I have a second Diver in a Scuba Tank that is also running hot...
Any suggestions are welcomed...
Sent from my iPad
Mine works fine when I refill, but it does the same thing when the juice gets to about wick level - a little juice escapes. I open up, clean up the juice, close up, and then it works fine until empty. I suspect there is a certain point when the pressure in the tank is just so, that a little juice comes flooding out. I've been too busy to try to figure it out, hopefully I'll have some time next week.
Interestingly, there isn't just juice around the tank, juice also comes up into the well of the brass nut. So somehow, for a brief point, something happens to produce a lot of pressure down on the juice, pushing a bunch into the Diver, which then comes out of the Diver any way it can. It's as if a vacuum is forming above the juice in the tank, and at some point that vacuum exceeds a certain force and escapes out the tank, with the inrushing air creating a sudden massive pressure. Once that stabilizes, it works fine again.
This does not happen to my Diver v2 in the Scuba, only in the BB.
And I do not have the heat issues you are experiencing in either one. I'm running a 2.7 ohm coil at max voltage, 5.5v.