Mercury Mariner 8/9.9HP 4-Stroke Factory Service Manual, Page 245Get this manual
Drum Removal IMPORTANT: The spring tension on the drum must be relieved before removal of the drum1Relieve the spring tension on the drum by untieing the knot in the starter rope and slowly releasing the starter rope, allowing the starter rope to wind fully onto the drum
3Turn the drum counterclockwise few turnsThis will help disengage the spiral spring from the drum
aTurn Drum Counterclockwise few Turns