I hope someone can help me on this, When flushing the black water tank water runs down the sides of the wheel wells. The area where the flush enters the black water tank is all sealed, is there any way to get a look at that connection?
I also have a 2003 Safari 25 with the black water flush - no prolems yet. The tanks are enclosed in insulated covers, so I would think you must remove those to see the entry point. Is your trailer still under warranty? If so, I would leave it to the dealer.
Go inside the trailer and look behind the cabinets that are one the same wall as the outside flush connection. You will find a check valve and an antisiphon device mounted on the walll with connections. If any of this leaks water will find its way out near the wheel wells. At least this is the way my 93 is built. I removed the pantry and two of the drawers and had easy access to this plumbing. Hope this helps.
29 ft Excello 1000
97 Expedition/Hensley Hitch/