Mercury MerCruiser 5.7 MPI User Manual

Section 7 - Troubleshooting
90-899883173 DECEMBER 2007 Page 99
Engine Will Not Start or Is Hard to Start
Possible Cause Remedy
Lanyard stop switch activated. Check the lanyard stop switch.
Improper starting procedure. Read the starting procedure.
Insufficient fuel supply. Fill fuel tank or open valve.
Faulty ignition system component. Service the ignition system.
Clogged fuel filter. Replace fuel filter.
Stale or contaminated fuel. Drain fuel tank. Fill with fresh fuel.
Fuel line or tank vent line kinked or clogged.
Replace kinked lines or blow out lines with compressed air to
remove obstruction.
Faulty wire connections. Check wire connections.
EFI system fault.
Have EFI System checked by an authorized Mercury
MerCruiser dealer.
Engine Runs Rough, Misses, or Backfires
Possible Cause
Remedy
Clogged fuel filter. Replace filter.
Stale or contaminated fuel. If contaminated, drain tank. Fill with fresh fuel.
Kinked or clogged fuel line or fuel tank vent line.
Replace kinked lines or blow out lines with compressed air
to remove obstruction.
Flame Arrestor dirty. Clean Flame Arrestor.
Faulty ignition system component. Service ignition system.
Idle speed too low.
Have EFI system checked by an authorized Mercury
MerCruiser dealer.
EFI System fault.
Have EFI System checked by an authorized Mercury
MerCruiser dealer.
Poor Performance
Possible Cause Remedy
Throttle not fully open. Inspect the throttle cable and linkages for proper operation.
Damaged or improper propeller. Replace the propeller.
Excessive bilge water. Drain and check for cause of entry.
Boat overloaded or load improperly
distributed.
Reduce load or redistribute load more evenly.
Flame arrestor dirty. Clean the flame arrestor.
Boat bottom fouled or damaged. Clean or repair as necessary.
Ignition problem.
See Engine Runs Rough, Misses or Backfires.
Engine overheating.
See Excessive Engine Temperature.
EFI System fault
Have EFI System checked by an authorized Mercury MerCruiser
dealer.
Excessive Engine Temperature
Possible Cause
Remedy
Water inlet or seacock closed. Open.
Drive belt loose or in poor condition. Replace or adjust belt.

Mercury MerCruiser 5.7 MPI Specifications

General

Brand	Mercury
Model	MerCruiser 5.7 MPI
Category	Engine
Language	English