high pressure between pump and divider would be bad divider in my opinion. but IF its only hi on one side of divider-- that would suggest problem on down the line causing a backup.
sounds like a long way around the block just to get across the street!
as a test, I would unhook the line thats hi and hook it directly back to tank and check pressure. If o.k. divider is ok. next go to the next thing in the line and check it the same way, run hose from backside to tank and check pressure ---lotta work but about the only way to track down the problem child.
In todays world, most companys have "no returns " policies and people they hire dont have a clue whats going on! -----As for surplus center--- I only ordered a couple things from them and that was 40 years ago-----great company back then, and I have no idea about how they are now!
