Needed to top up the fuel tank on the buggy I drive (Painshill Park) so fetched the jerry can but could not open the latch. Gave it all my huff 'n puff with no movement. Asked two colleagues and both equally stumped.
The manager appeared and watched for a while before saying "If you remove the locking pin, it will be easier"
DOH !!!!
Because of the cap design it looked like the pin was part of the hinge. [/size]