2001-2002 Yamaha 50HP F50Z/T50Z Ouboard 4-stroke engines service manual, Page 124Get this manual
IpOWRIIfriJ: IPower unit Symptom: Engine cracks, but will not start Check the ignition system Check the fuel system Check the compression pressure of power unit
Check the ignition spark using the spark gap tester
j WARNING
Do not touch any of the connections of the spark gap tester leads Do not let sparks leak out of the removed spark plug caps Keep flammable gas or liquids away, since this test can produce sparks
Below the spark gap specification?
Check the ignition system output peak voltage
Check the condition of the spark plugs