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Master Tech
Master Tech, Marine Technician
Category: Boat
Satisfied Customers: 1168
Experience:  Evinrude Master Technician with 30 years of experience.
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late 1980s johnson 70 hp - have no spark on any spark plug

Customer Question

late 1980s johnson 70 hp - have no spark on any spark plug - ignition turns over good - has fuel pressure - no spark - disconnected black and yellow wire at ignition switch - still no spark- help
Submitted: 7 years ago.
Category: Boat
Expert:  Master Tech replied 7 years ago.

Remove the blk/yel from the amphenol connector at the powerpack and see if you regain spark.


If you do, you have a short in the blk/yel between the keyswitch and the powerpack or a defective keyswitch or emergency stop switch.


Another means of troubleshooting the boatside wiring is to connect a different control box to the engine and re-test though this may not be an option for you.


Unfortunately, unless you find a shorted component on the boat side wiring or a broken lead in the engine harness, you will need the use of a special tester (peak reading voltmeter) to check cranking output on the stator, timer base, and powerpack.


They cannot really be tested without the use of this meter.


If you are a betting person, I would try a new powerpack first.




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