5-3
GB
E. Engine power loss.
1. Propeller damaged.
1. Have propeller repaired or replaced.
2. Propeller pitch or diameter incorrect.
2. Install correct propeller to operate out-
board at its recommended speed
(r/min) range.
3. Trim angle incorrect.
3. Adjust trim angle to achieve most effi-
cient operation.
4. Motor mounted at incorrect height on
transom.
4. Have motor adjusted to proper transom
height.
5. Warning system activated.
5. Find and correct cause of warning.
6. Boat bottom fouled with marine growth.
6. Clean boat bottom.
7. Spark plug(s) fouled or incorrect type.
7. Inspect spark plug(s). Clean or replace
with recommended type.
8. Weeds or other foreign matter tangled
on gear housing.
8. Remove foreign matter and clean lower
unit.
9. Fuel system obstructed.
9. Check for pinched or kinked fuel line or
other obstructions in fuel system.
10. Fuel filter clogged.
10. Clean or replace filter.
11. Fuel contaminated or stale.
11. Fill tank with clean, fresh fuel.
12. Spark plug gap incorrect.
12. Inspect and adjust as specified.
13. Poor connections or damaged ignition
wiring.
13. Check wires for wear or breaks. Tighten
all loose connections. Replace worn or
broken wires.
14. Failed ignition parts.
14. Have serviced by a Yamaha dealer.
15. Specified engine oil not used.
15. Check and replace oil with specified
type.
16. Thermostat faulty or clogged.
16. Have serviced by a Yamaha dealer.
17. Fuel pump damaged.
17. Have serviced by a Yamaha dealer.
18. Fuel joint connection incorrect.
18. Connect correctly.
19. Heat range of spark plug incorrect.
19. Inspect spark plug and replace it with
recommended type.
Trouble
Possible Cause
Remedy
U69J73A0.book Page 3 Monday, March 31, 2003 2:44 PM