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Ignition coil resistance question
Posted: Wed May 23, 2012 8:24 pm
by crowbird
Have trouble with spark on 88 elite 50. Checked resistance across ignition coil and the reading was .4 ohms versus the manual's range of .1-.2ohms. Trying to determine if my coil is ok.
Re: Ignition coil resistance question
Posted: Wed May 23, 2012 8:32 pm
by mousewheels
Checked resistance across ignition coil and the reading was .4 ohms versus the manual's range of .1-.2ohms. Trying to determine if my coil is ok.
Could be your probe leads are part of the resistance measurement.
Short across your meter probes record the reading. Now measure your coil primary and subtract the difference. That will get your measurement closer. If your meter resolution is limited to 0.x ohms, it may still show 'off' readings.
Re: Ignition coil resistance question
Posted: Wed May 23, 2012 8:45 pm
by crowbird
Thanks......what kind of reading indicates a bad coil?
Re: Ignition coil resistance question
Posted: Wed May 23, 2012 9:08 pm
by mousewheels
Thanks......what kind of reading indicates a bad coil?
Resistances measurements on coils and CDI are not foolproof - sometimes a failure can read within resistance spec.
- An open or obviously high resistance is a problem.
- A short primary to secondary would be a problem. However design of coil may prevent this failure.
- Shorted turns within a coil (a short between turns of the primary or short between turns of the secondary coil) may not be detected by a resistance measurement.
- Internal arcing not likely detected.
Re: Ignition coil resistance question
Posted: Wed May 23, 2012 9:13 pm
by abreen89
mine was reading .5 ohlms so i thought that was the problem got a new one and didnt help found out it was my spark plug (never substitute ngk for an autolite) put the .5 one back on and it worked fine it might of been my meter but not sure....
Re: Ignition coil resistance question
Posted: Wed May 23, 2012 10:00 pm
by crowbird
Thanks........Are you recommending NGK or Autolite?
Re: Ignition coil resistance question
Posted: Thu May 24, 2012 12:30 am
by abreen89
NGK ......................autolite is junk
Re: Ignition coil resistance question
Posted: Thu May 24, 2012 10:11 am
by crowbird
Thanks......Have ordered some and will pick up this am. Will give it a try before I change coils.