Section 6
DIAGNOSTIC TESTS
5.Set voltmeter to measure DC voltage.
6.Remove Wire 15 from the
RESULTS:
Repair or replace any wiring that did not have continu- ity.
If voltage was not measured in Step 6 repair wiring between the Starter Contactor Relay (SCR) and the
If all steps passed repair or replace Wire 16 between the Starter Contactor (SC) and the Starter contactor Relay (SCR).
Test 29 - Check Ignition Spark
PROCEDURE:
A commercially available spark tester may be used to test the engine ignition system. One can also be purchased from Generac Power Systems (Part No. 0C5969).
1.Disconnect a high tension lead from a spark plug.
2.Attach the high tension lead to the spark tester terminal.
3.Ground the spark tester clamp by attaching to the cylinder head (see Figure
4.Crank the engine rapidly. Engine must be cranking at 350 rpm or more. If spark jumps the tester gap, you may assume the ignition system is working properly. Repeat on remaining cylin- der spark plug.
5.If spark jumps the tester gap intermittently, the problem may be in the Ignition Magneto.
Figure 6-37. – Testing Ignition System
Figure 6-38. – Checking Engine Miss
RESULTS:
Refer back to the Flow Chart
Test 30 - Check Spark Plugs
PROCEDURE:
Remove spark plugs. Clean with a commercial sol- vent. DO NOT BLAST CLEAN SPARK PLUGS. Replace spark plugs if badly fouled, if ceramic is cracked, or if badly worn or damaged. Set gap to 0.040 inch (1.016 mm). Use a Champion RC14YC (or equivalent) replacement spark plug.
SET PLUG GAP AT 0.040 inch
(1.016 mm)
Figure 6-39. – Setting Spark Plug Gap
RESULTS:
1.Clean and regap or replace sparks plug as necessary.
2.Refer back to the Flow Chart.
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