1986+ Mercury 6/8/9.9/10/15HP 2-stroke Factory Service Manual, Page 207Get this manual
POWER TRIM
Troubleshooting
IMPORTANT: Determine if Electrical or Hydraulic problem exist
Hydraulic Troubleshooting
CONDITION OF TRIM SYSTEM ABCDEFGHIJKLTrim motor runs; trim system does not move up or downDoes not trim downDoes not trim upPartial or Jerky downupThump noise when shiftingDoes not trim under loadDoes not hold trim position under loadTrail out when backing off from high speedLeaks down and does not hold trimTrim motor working hard and trims slow up and downStarts to trim up from full down position when IN trim button is depressedTrim position will not hold in reverse1Low oil level2Pump assembly faulty3Tilt ram piston O-ring leaking or cut4Check condition of battery5Broken motorpump drive shaftPROBLEM 1, 2, 1, 2, 1, 1, 2, 1, 2, 2, 2, 1, 2, 2, 3