[tsubaki]

The picture shows a cover plate below the controls and hoses duct and above the bracket. Remove the cover plate and see if you can access any wood material from there.
Other places to try are the silicone plug for the transducer wire thru hole and the lifting rings.
Can't imagine the motor falling off unless your not attentive to possible problems. Case and point "I don't know how I ran out of gas". The bells, blinking lights and fuel gauge should have been a clue.