Psubs people like Hugh Fulton, Cliff Redus,  Brian Hughes & myself did a lot of experimentation in using venting pressure regulators. Cliff found the venting hole too small & it caused a pressure build up in his system. <div>I found it difficult to find a replacement non corrosive spring for the relieving system.</div><div>It had to be mounted upside down to help prevent water ingress & the 316 regulators were relatively inexpensive.</div><div>As the 1st stage regulator can feed in to a manifold a beer brewing over pressure regulator can screw in to the manifold & solve the problem.</div><div>Alan<br><br><div id="ymail_android_signature"><a id="ymail_android_signature_link" href="https://mail.onelink.me/107872968?pid=nativeplacement&c=US_Acquisition_YMktg_315_SearchOrgConquer_EmailSignature&af_sub1=Acquisition&af_sub2=US_YMktg&af_sub3=&af_sub4=100002039&af_sub5=C01_Email_Static_&af_ios_store_cpp=0c38e4b0-a27e-40f9-a211-f4e2de32ab91&af_android_url=https://play.google.com/store/apps/details?id=com.yahoo.mobile.client.android.mail&listing=search_organize_conquer">Yahoo Mail: Search, organise, conquer</a></div> <br> <blockquote style="margin: 0 0 20px 0;"> <div style="font-family:Roboto, sans-serif; color:#6D00F6;"> <div>On Sat, 24 Jan 2026 at 9:03 am, Sean T. Stevenson via Personal_Submersibles</div><div><personal_submersibles@psubs.org> wrote:</div> </div> <div style="padding: 10px 0 0 20px; margin: 10px 0 0 0; border-left: 1px solid #6D00F6;"> Any industrial pressure reducing regulator with pressure tracking bias and  "self-relieving" or "self-venting" functionality should serve this purpose. Look at the Tescom 44-4000 series as an example.<br clear="none"><br clear="none">Sean<br clear="none"><br clear="none"><br clear="none">-------- Original Message --------<br clear="none">On Friday, 01/23/26 at 11:49 Jon Wallace via Personal_Submersibles <<a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none">Hi Rick, the second stage setup I understand.  My question was directed to Hank regarding his system of using sequential 1st stages since there's no escape for the pressurized air in the motor the same way there is when using a second stage.  I've seen Stanley describe just letting that air blow out through the thruster o-rings but seems like that would come with some risk with the Minn-Kota motors.<br clear="none"><br clear="none">Jon<br clear="none"><br clear="none"><br clear="none"><br clear="none"><br clear="none">On Friday, January 23, 2026 at 02:05:39 PM EST, Rick Patton via Personal_Submersibles <<a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><br clear="none">The air as it expands comes out the two stage regulator that is mounted low.<br clear="none"><br clear="none">On Fri, Jan 23, 2026 at 7:08 AM Jon Wallace via Personal_Submersibles <<a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none">> How do you release pressure from the motors when surfacing?<br clear="none">><br clear="none">><br clear="none">> On Friday, January 23, 2026 at 08:25:20 AM EST, hank pronk via Personal_Submersibles <<a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none">><br clear="none">> Hi Rick, I use a first stage regulator with the spring removed to act as the pressure compensator.  I use a first stage to bring down the pressure from the tank as normal, then send that air to the second first stage regulatow with spring removed, then to the motors.  The output pressure to the motor is a constant 2 psi or so.  I tie all the motors and arm to the one regulator.  I have had no luck with the scuba second stage regulator set up.  Tested to 400 feet, no issues.<br clear="none">> Hank<br clear="none">><br clear="none">><br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><div class="yqt4386197229" id="yqtfd30364"><br clear="none"><br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" hre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