only fire on #1 plug

44Darren44

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Aug 21, 2009
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!977 85hp evinrude. only fire on # 1. If I switch trigger to any other, that plug will fire. The problem is... there is 8 ohms across 1-3 and 2-4, and 5 v ac on all four. This test tells me that triggers should be working, am I correct or should I replace trigger plate?
 

iwombat

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Jul 12, 2006
Messages
3,767
Re: only fire on #1 plug

I'm not sure what you're calling a "trigger".

Are you referring to the leads from the timer base to the power pack, or the leads from the power pack to the ignition coils?
 

iwombat

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Jul 12, 2006
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3,767
Re: only fire on #1 plug

Ok, so rearranging the leads form the timer base and still only #1 fires. I don't think the problem is in your timer base. If you change the leads from the powerpack to the coils does that same coil still fire?
 

44Darren44

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Aug 21, 2009
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Re: only fire on #1 plug

rearranging leads make others fire. changing #1 and #2 makes #2 fire. leads me to believe timer base is bad. But tests good with continuity (8 ohms) and 5 volts. Is there any other way to test?
 

iwombat

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Jul 12, 2006
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3,767
Re: only fire on #1 plug

Hrm, so changing the timer base leads moves the problem?

Yeah, I'd suspect the timer base. That base is adjustable for gap to the flywheel. Sometimes the adjustment cures these kinds of problems, other times not. You'll need the adjustment tool, which sells for something like $8. Worth a shot given that a new timer base will be upwards of $150.
 

44Darren44

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Aug 21, 2009
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Re: only fire on #1 plug

I took timer base apart and moved the #1 wire above the sensor. I have spark on all cylinders now. The wire must have been arcing. I also notice before that #1 plug was firing twice. This will get me going until I get a new one. Thanks so much for the response.
 
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