Woodward 723PLUS Technical Manual page 98

723PLUS Digital Marine Control
Symptom
Engine will not start
(actuator moving to start
fuel position).
Engine overspeeds on
start.
Engine overspeeds on
start or causes excessive
smoke on start.
Engine speed not
regulated.
88
Cause
1. Actuator linkage not
connected.
2. Start fuel limit too low.
3. Engine problem.
1. Actuator and/or linkage
problem.
2. Speed control dynamics
adjustment.
1. Start fuel limit set too
high.
1. Improper linkage
adjustment.
2. 723PLUS control
problem.
3. Mechanical governor in
control.
Test/Remedy
1. Verify the linkage from actuator to fuel rack is properly
connected. Verify collapsible link functioning properly, if used.
2. Check the start fuel limit level. Increase start fuel limit as
necessary.
3. Engine fuel, air, ignition, etc. problem. Engine fuel and/ or air
solenoid(s) may still be shutdown from calibration procedure.
Troubleshoot engine as recommended by manufacturer.
1a. Verify that fuel rack is not binding and linkage is properly
adjusted.
1b. Actuator drive rotation incorrect.
1c. Verify the actuator and 723PLUS control are the same
action (forward or reverse). Verify that as the 723PLUS control
actuator command goes to maximum fuel, the fuel rack is
moved in the increase fuel direction. Actuator terminal shaft
position should be proportional to the actuator command.
2. Speed control PID dynamics may be adjusted for sluggish
operation. Attempt to start engine by controlling fuel rack
manually or by reducing the speed reference. Adjust dynamics
for better response.
1. Reduce start fuel limit to some level slightly above (10%–
20%) the percent actuator driver level needed to run the
engine at idle speed.
1. Verify actuator is capable of reaching the minimum and
maximum fuel rack positions.
2a. 723PLUS control is not powered up. Verify proper power
supply operation.
2b. Verify proper CPU status (CPU LED illuminated).
2c. 723PLUS control is STOP or shutdown mode. View
actuator shutdown mode with hand held programmer.
2d. Fuel limiter in control. View fuel limiter control status with
hand held programmer.
3a. Engine may be running on ballhead back up if used. Verify
by attempting to change engine speed with speed setting input
for mechanical governor. Manual override device on actuator
may be active.
3b. Actuator load limit setting on actuator set too low. Increase
load limit so 723PLUS control takes control of engine speed.
3c. Actuator wiring may be open. Check wiring and continuity
from 723PLUS control to actuator.
Manual 26482
Woodward