Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 65Get this manual
1998 OFI Troubleshooting Guide (continued) Symptom 6Engine runs rough above 3000 rpm Cause 6.1 Fouled spark plug See 3.2 Action
6.2 Speed Reduction 6.3 Low air pressure in rails 6.4 TPS malfunction 6.5 Crank Position Sensor mis-adjusted
See See 1.2 See 2.5 Gap between sensor and flywheel should be 0.015 in- 0.040 in(0.38mm1.01 mm) Check battery andor alternatorCheck electrical connectionsCheck water pump impellercooling systemCheck oilCheck electrical connectionCheck electrical connections
7Speed Reduction (RPM reduced or limited to 3,000)