My 300 is still not running in the past I have checked the spark and it seamed like a good hot spark but after working on it for about two hours the spark is weak at best. I have replaced the spark plug and the plug boot. I have the service manual and the diagram for the ignition system shows a secondary coil going to the spark plug but also shows a CDI box is there a way to test the cdi? and is there a way to test the coil? The book only gives a sequence to test ingnition system with weak spark and running not weak spark and not running. Any help would be appreciated

 

Liberty,what color is the spark,if its not blue,something is wrong.Check all connectors to and from coil and CDI unit,look for corrosion on the pins.check the coils primary and secondary resistance,service manual should tell what values should be.Good luck hope this helps.

 

Spark has been blue all along until I worked at starting it for such an extended time and then it was orange and was not jumping accross from the electrode to the spark plug tip but was sending little lightning buzzes to the rim of the plug. I will check the connections in the morning. unfortunately the manual says to use a digital vom and mine is anolog will it still work? If not I will go and get one to use. I work on old things like my 1939 ford 9n I am not used to the new stuff that requires up to date equipment [img]i/expressions/face-icon-small-smile.gif[/img] Thanks for your help

 

Liberty,
From my experience, most often if you are getting spark at all, the CDI is working. If the spark is weak, check the coil. The CDI more or less sends a signal to the coil, which is supposed to bump up the voltage to make it spark.
Also, spark will be weak if the battery is weak.
Your spark plug may also be a little fouled. If it is working right, it should spark across the electrode gap, or not at all. If it is buzzing to the rim of the plug, the spark is likely flowing through some fouling to get there, or the insulation around the electrode is faulty.