Ignition coil resistance question

[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.

[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.

[crowbird]

Thanks......what kind of reading indicates a bad coil?

[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.

[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....

[crowbird]

Thanks........Are you recommending NGK or Autolite?

[abreen89]

NGK ......................autolite is junk

[crowbird]

Thanks......Have ordered some and will pick up this am. Will give it a try before I change coils.