Originally Posted by martin300662
Originally it would have dropped forward (hinge at the bottom) and the flap acts as a funnel, to collect water into the hose attached to the fixed section.
It isn't uncommon for the rigid plastic fixed section to be cracked where the lock engages.
Of course it doesn't normally have the bolt latch, but I assume that is just to keep the flap closed.
Thank you for the reply. I assume that the lock is the tapered cylindrical hole above the flap? Do you have a picture of the key that you could post at your convenience? or is it just a regular key and I'm missing the cylinder? I've ordered the owners manual, that should shed some light on my troubles.
No hurry, the water system needs a complete overhaul so the filler door is just one more part in the project.