Lay the door flat on a soft object (i.e. towel) use a screwdriver as a lever. With both hands pushing on the lever, force the hinge back out until you can flick the retaining clip back in to place. The hinge is strong but can easily be pulled back out.
Lincoln Appliance NZ
July 2017
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Removed oven door from Bosch Oven FD 9604 and hinge has shut?