brunnhilde's fresh water filler cap

When I finished filling the potable water into Brunnhilde's water tank, I proceeded to replace the filler cap and lock it. To my surprise the lock cylinder popped out when I withdrew the key.

I could also hear a click of some spring-loaded bits inside the filler cap dislodged. I immediately it is not good, and the filler cap is likely broken and in need of a replacement. This will have to come from Europe. Still I took care to remove the cap hoping none of the small piece parts are lost.

Upon initial examination a repair does not look too promising. It appears that the bits cannot assembled back into the cavity of the cap without dissembling the cap. The body of the cap is made of 3 plastic parts and were design not for dissembling after they are snapped together during manufacturing.

the black plastic piece functions as the latch and the cast metal cylinder serves as an actuator cam that move the spring-loaded plastic latch; the plastic latch is a bit bend from the stress placed on by one rotating the filler cap - a rather weak design

With a bit of fussing with a sturdy tweezers I was able to insert the plastic latch and spring back into the bottom of the lock cylinder well. I was very surprised this is possible. Next is to drop in the cast metal cylindrical cam.

the cast metal cylindrical cam is rotated by the lock cylinder

As I examined what kept the lock cylinder in place, I discover it is just a small dab of what appears like epoxy. No doubt the thermal expansion and contraction the cap subjected to the elements have caused the glue bond to fail.

Instead of just gluing the cylinder back with epoxy I ground rough the top collar of the lock cylinder as well as rough up the surface of the plastic.

a bit of West System's epoxy and 24 hours later the cap is repaired