Logo

Ignition wire shows spark on one cylinder when positive lead touches battery terminal.

livetofish64

Contributing Member
This is a 1970 85 hp Evinrude Hydroelectric Shift that when the key is on shows spark with a spark tester when you touch the positive lead to the battery. What would cause this?
 
Last edited:
Sounds normal to me.----That motor has a BATTERY powered electronic ignition.------You might see a spark when you turn it on and off.-----What is your motor doing / not doing ?---Why the question ?
 
Hey racerone, thanks for responding. This is a new to me motor and I have been giving it a Health check. I’m just wondering why I’m getting a stray current on cylinder #3 when i connect my spark tester this particular cylinder lights the bulb on the tester when I touch the motor’s positive lead to the battery. It goes out after making connection but lights up when tapping the lead to the battery terminal. This just doesn’t seem right. None of the other cylinders light up like this.
 
Last edited:
It might do that if rotor is pointing to that cylinder. Try turning the motor and see if spark moves to another cyl.
 
Your absolutely right. It moved to other cylinders when I cranked it over. So this is normal. I learned something today. Thank you very much!
 
I just got lucky! Really never tried it myself....could be a decent way to easily check spark by one at a time.
 
I started the motor in a 55 gal drum but only for a few seconds. I think it will run continuously but I might have to go through the carbs.
 
We spend alot of time helping on the forum, these guys are my mentors. Thousands of years of experience here. Your very welcome....I learn from the posts all the time.
 
This is a 1970 85 hp Evinrude Hydroelectric Shift that when the key is on shows spark with a spark tester when you touch the positive lead to the battery. What would cause this?

In touching the battery terminal, you're acting as a grounding point, in essence playing the part of a manual point setting or a electronic one within the pulsepack of that Battery Capacitance Discharge ignition system each time you complete the circuit. Normal happening, nothing to be concerned about...... Unless, the key is On, the engine in gear, and you happen to be leaning over the transom at the time! ;)
 
Heh, heh, yes there have been accidents. Spontaneous starting without running the starter, running backwards, loud backfire when shutting it off, etc. Some seemingly weird preventative devices have been added to prevent that stuff.
 
Ha! Never thought of that...yes it could start. Be like one of those big Merc "dockbusters". Just imagine.....offering a product like that in today's world. He...he...he! With YouTube besides....out there to record all the "fun".
 
Back
Top