I have two heads on my boat that both have the Sealand (now Dometic) Vacuflush system. The port side serving master stateroom has been totally trouble free for the 8 years I've had the boat. The stbd side is a whole different world. We continually have problems with it. The vacuum pump runs excessively, sometimes even when nobody has flushed. We keep looking for a vacuum leak and replacing hoses but to no avail. We have heated up hose ends to ensure good fit and double clamped. Still has issues. Worse yet, we have had three pumps fail over past few years whereby the bellows completely blow out and dump doo doo all over the centerline bilge space where the pumps and equipt are located. Makes quite the mess. We have installed complete new pump assemblies each time and checked for blockages and yet just had same happen again. We are at our whits end. What would cause the pump to blow out like that? Does it have to be a blockage somewhere? We are are about to once again remove all hoses and look for blockage and install a new pump. Both heads have the siphon break loops under the master stateroom bed. The check valves were removed and capped long ago before I got the boat. Do I need to leave these siphon break loops even though the check valve ports are capped? It seems like they are adding like 20' of unnecessary hose. Can I remove those to shorten the run or do they still do something even though the check valves are capped?