12V system with 6V coil - no spark

[5030tinkerer]

Thanks for the tip Soundguy. Can you elaborate on what I am checking the ignition switch for?

 

[patrick_g]

Interesting. Given that my ballast resistor is indeed wired in series to the OEM coil and that only one wire connects to the positive side of the coil (that is, the wire coming from the resistor), I don't understand how the resistor could be bypassed in the running mode.
.

The resistor is NOT bypassed in the running mode. It is bypassed in start mode (on many applications) as this gives a better spark for starting as during starting the battery voltage is pulled down considerably by the heavy load.

Pat

 

[Soundguy]

The resistor is NOT bypassed in the running mode. It is bypassed in start mode (on many applications) as this gives a better spark for starting as during starting the battery voltage is pulled down considerably by the heavy load.

Pat

Appears his system doesn't incorporate any bypass at all.. which is what I figured for an old wisconson engine.

soundguy

 

[Soundguy]

Thanks for the tip Soundguy. Can you elaborate on what I am checking the ignition switch for?

Here's the text from my last post: with spelling correction

"check the ignition switch as well.. they can get resistive contacts"

resistive contacts means there is added ressitance in the circuit.. more resistance = less primary current= less magnetic field=less secondary current=less KV potential = marginal spark or no spark at the spark gap.


anythong other then nearly 0.0 ohms across the switch out of circuit or replace switch.. can also do a votlage check across switch to see if it is dropping volts.. if so.. it has ressitance..

soundguy

 

[5030tinkerer]

Well, thanks everyone! The skid loader is working again! Jon's original test and Soundguy's suggestion as to what was wrong got me there!

I pulled the cap off as Jon suggested, spun the motor so the points were closed, connected a spark plug to the coil wire, manually opened the points in wanten anticipation of a spark, and....NOTHING. Certainly helps troubleshooting to know what you are looking for, when.

A few seconds with a continuity tester proved that the isolator bushing on the little bolt on the side of the distributor had failed in its duties - the bolt was shorting out to the distributor. The isolator had developed a little line of rust from the cap to the bolt, thereby grounding the bolt out. I took it all apart, used a dremel with a wire wheel to clean everything up (if you don't have a Dremel, they are awesome little tools, don't even mess with the knock-offs), put it back together, and the machine roared to life nearly immediately.

It seems like it is always the little things.

THANK YOU!

 

[Soundguy]

glad you got her going.. those feed thru insulators are a big failing point on many breaker ignition systems. I have used license plate nylon inserts.. or in a pinch.. a wire and glop of rtv to get a machine going.

soundguy