checking mag on 38 JD D

mul-skiner · Jul 11, 2008

Hi is there a way to check if a mag is good or not other than the spark method?

Bob · Jul 11, 2008

What problem are you having??? OBVIOUSLY, if it throws a good, HOT spark, it is good.

mul-skiner · Jul 11, 2008

Well the tractor starts after a lot of trys carb rebuilt,new plugs points and condensor How far should the spark jump or is there away to check it with a meter or something? Thanks

Nebraska Kirk · Jul 11, 2008

There are meters made for checking magnetos, but they are usually expensive. The mag should throw a blue spark at least 1/4 inch, if the spark is yellow, or will not jump 1/4 inch, then your magneto may need a new coil.
Nebraska Kirk

John T · Jul 11, 2008

The spark method isnt all that bad, look for a good bright visible BLUE spark around 3/16 to 1/4 inch or so versus any thin wimpy yellow looking one. If the start/impulse spark is weak the mags spring may be weak, it should produce a loud sharp SNAP when the impulse trips versus a faint dull clunk like a weak spring may cause. As far as good hand starts the start/impulse TIMING IS CTITICAL, it needs to be right near dead TDC cuz if too late shes harder to start but if too fast the flywheel can kick back. Also the right carb and choke settings are important, DO NOT OVERCHOKE AND WET GAS FOUL THE PLUGS....

John T

checking mag on 38 JD D

mul-skiner

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Bob

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mul-skiner

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Nebraska Kirk

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John T

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