[MaxwellD]

Originally Posted by Kyle and Lisa;1285644 that does [ATTACH

16256[/ATTACH]not fix your leak, you just can't see now, because it's on the inside.

You are correct Sir!. After a few days, same issue occurred. I pulled the black tank flush inlet and discovered there was no check valve in there at all - so as the tank filled partially to the level of the flush nozzle, fluid simply flowed towards the inlet and leaked out under the cover cap in the convenience center.
I have replaced it with one that has a functional check valve. So far, so good.