I'm trying to figure out why the shower sump on my 2006 First 36.7 isn't pumping out. The drain is clear. The pump located behind the port upper settee cushion runs when the switch in the head is closed. All the strainers are clear. There appears to be a second pump under the galley sink just upstream from the through-hull that I assume is where the sump ultimately drains. This pump doesn't run when the switch in the head is closed. The through-hull is open and I'd think that even if the second pump was in the flow that water from the sump could still pass it when the upstream pump was running. What am I missing?