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<div>Brian,</div><div>If your tank is full of water and you pump it dry, you will have negative pressure in the sub, but not much. It should or might seal the hatch. </div><div>Hank</div><div><br></div>
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On Wednesday, April 17, 2019, 7:12:43 PM MDT, Brian Cox via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="yiv0662027082"><div style="font-family:Arial, sans-serif;font-size:10pt;"><font size="2" style="font-family:Arial, sans-serif;">Hi All, </font><div style=""><font size="2" style=""><font face="Arial, sans-serif"> I have this little pressure pump for my internal ballast and I'm wondering if I could use it to pull a vacuum on my sub. I was thinking it would be nice to do before I submerge, to seal the hatch. The pump I have is a 100W 12volt pump that puts out 150psi and a flow of 8L / min. Would I need to expel water to pull the vacuum? My internal ballast is about 5 1/2 gallons . Not sure if the pump would pump air efficiently.</font></font></div><div style=""><font size="2" style=""><font face="Arial, sans-serif"><br></font></font></div><div style=""><font size="2" style=""><font face="Arial, sans-serif">Brian</font></font></div><div style=""><font size="2" style=""><font face="Arial, sans-serif"><br></font></font></div><div style=""><font size="2" style=""><font face="Arial, sans-serif"> </font></font></div></div></div>_______________________________________________<br>Personal_Submersibles mailing list<br><a ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br></div>
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