Guardian Technologies 4760, 4456, 4390, 4389 Section, Diagnostic Tests, Part, Engine Ground Harness

SECTION 4.4

DIAGNOSTIC TESTS

PART 4

DC CONTROL

4.Tighten both mounting screws.

5.To remove the thickness gauge, rotate the flywheel.

6.Repeat the above procedure for the second magneto.

Figure 23. Setting Ignition Magneto (Armature)

Air Gap

7.Repeat Test 55 and check for spark across the spark tester gap.

8.If air gap was not out of adjustment, test ground wires.

9.Set the VOM to the diode test position. The meter will display forward voltage drop across the diode. If the voltage drop is less than 0.7 volts, the meter will “Beep” once as well as display the voltage drop. A continuous tone indicates CONTINUITY (shorted diode). An incomplete circuit (open diode) will be displayed as “OL.”

10.Disconnect the engine wire harness from the ignition magnetos and stud connector (Figure 24).

Figure 24. Engine Ground Harness

Figure 25. Diode Failure Diagnosis

11.Connect the positive (+) test lead to Connector ”A” (as shown in Figure 26). Connect the negative (-) test lead to Connector “B.”

a. If meter Beeps once and displays voltage drop, then the diode is good.

b. If the meter makes a continuous tone, the diode is bad (shorted) and the harness must be replaced.

c. If the meter displays OL, the diode is defective (open) and the harness must be replaced.

Figure 26. Engine Ground Harness Test Points

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