Power in 1 plug

BigJoe

Recruit
Joined
Jun 14, 2002
Messages
3
I have a 1975 115Hp evinrude I am showing power in only No2 spark plug the book says to put a No s80 Neon tester on it where can I get the tester or does any body have any ida what to check I had a new power pack installed about a month ago I hope its not it
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: Power in 1 plug

BigJoe.... Remove the spark plugs. Rig up a spark tester whereas you can check each s/plug wire to see if the spark will jump a 7/16" gap.<br /><br />If, as you say, you do not have spark (or very weak spark), remove the black/yellow wire from the powerpack and retry the spark test. If you now have a good strong blue flame on all cylinders, you have either a faulty ignition switch or a short in the wiring harness.<br /><br />If with the black/yellow wire off, you had good spark, you can test the ignition switch by reconnecting the black/yellow wire to the powerpack, then removing that black/yellow wire at the back of the ignition switch, then recheck the spark. If you have spark, the switch is faulty. keep us informed.
 

BigJoe

Recruit
Joined
Jun 14, 2002
Messages
3
Re: Power in 1 plug

Tnx Joe<br />What I did was I took a induction timing light and put it on each spark plug wire and only no2 cyl lights up the timing light no spark in any other cyln
 

almost retired again

Chief Petty Officer
Joined
Feb 9, 2002
Messages
438
Re: Power in 1 plug

Hi BigJoe,<br />Keep in mind that the batrery must spin the engine over really fast to develope a rear good spark. Engines in those years didn't start real good unless the battery was at full charge.<br />Follow Joe reeves advice first, but you can check the charge coil and sensor coil output with a peak reading voltmeter, or (I may catch some flak for this) a regular AC voltmeter. Multiply the reading that you get by 1.414 to get the peak value. I would suspect the charge coils should read approx. 145 V or better with a regular meter, and if the sensor coil voltages cause the meter to deflect I would say they are OK. I have used this method several times in the last 20 years when I didn't want to take my expensive meters to the water.<br /><br />Hope this is of some help
 

BigJoe

Recruit
Joined
Jun 14, 2002
Messages
3
Re: Power in 1 plug

Hi Tnx with battery at full charge and blk and ylw wire off still no spark in any plugs but no 4 thought it was no 2 but was mistaken good spark in no 4 driving me NUTS ha
 
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