Mercury 225 EFI, Service Manual

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FUEL INJECTION
90-884294 Page 3B-21 OCTOBER 2001
Fuel Rail Electrical/Fuel Determination
•
Perform all preliminary checks page 3B-13.
•
Adequate fuel pressure (41 to 45 psi; 283 to
310 kPa) follow Low/High Fuel Route Flow
Charts.
•
Run engine @ idle and with DDT, perform
cylinder load test.
No RPM change on cylinder(s),
indicating problem in cylinder(s).
RPM decreases (on each cylinder).
Perform Fuel Injector load test.
Fuel delivery OK.
Defective injector or broken cir-
cuit to injector.
Perform Induction Manifold
Disassembly and inspection.
Perform compression check on
problem cylinder.
Low or no compression on cylinder.
Compression OK.
Inspect cylinder bore. Refer to
Section 4 for disassembly.
NOTE: Injector filters must be
inspected prior to reassembly.
Check:
1) Damaged reeds
2) End cap seals
3) Crankcase split line leak
4) Crankshaft sealing rings
Results Results
Results
Results Results
Fuel Injector has audible click.
Results
Injector is functioning properly
Results
Fuel Injector does not have audible click.
Perform Ignition Coil load test.
Ignition spark OK
Weak or no ignition spark
Replace defective coil, spark plug
or wiring
Results