How points ignition system works.

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Bubba1235

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After reading a lot of posts its apparent some folks just do not understand how their points type ignition system works. Of course when you don't understand how something works, it makes it near impossible to trouble shoot and repair it.

With that in mind I put together a small PowerPoint presentation to explain it. Our friend Don S has generously offered to host the presentation on his 4shared site so anyone wishing to may download it. (Very small download)

http://www.4shared.com/document/5yhbEx3S/Ignition_System.html?
 
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flargin

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Re: How does the Ignition work? (Sticky candidate?)

PLEASE REFER TO THE POST AT THE END OF THIS TOPIC FOR THE DOWNLOADABLE POWER POINT DISPLAY...

Re: How does the Ignition work? (Sticky candidate?)

Really nice.

Would really appreciate the addition of two other unknowns for many.

Dwell, and resistors/resistor wires/points would close out the picture for many.

Lots and lots of thanks. I think this may be a great way to help build up knowledge, a "library" of info.
 
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Don S

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Re: How points ignition system works.

Will make this a sticky for a while so most get a chance to read it. I will also be putting it in the Adults Only sticky. Good job Bubba :)
 

achris

More fish than mountain goat
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May 19, 2004
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Hi All,

Due to the upgrade, the original post with the power point display for this thread was mislaid. The IT team have found it and given me the link, so I will post it here...

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http://www.4shared.com/document/5yhb...on_System.html

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As for "Dwell", that is merely the time (in degrees of crankshaft rotation) that the points remain closed. Effectively, the smaller the dwell, the larger the points gap, the longer the dwell, the smaller the points gap. From the pps display and this knowledge, you can see that the points need to stay closed for long enough for the coil to charge (magnetic field saturated). To small a dwell and the coil will not be fully charged, and the spark will be weak. Too long a dwell and the points will burn as they open (gap too small to avoid a hard arc)...

The resistance wire is to limit the current flowing through the coil. Coils are designed to work at 7 volts, so the resistance ( discreet or as a wire) is not reducing the performance of the coil. The bypass wire from the stater to the coi + is to provide a full kick to the coil as the engine is cranking. Often the battery voltage will be down around 9 or 10 volts and so the coil voltage through a resistance will also be down, often as low as 5 volts, which would cause a weak spark. And at cranking is when the engine does require a good strong spark.

Hope this all helps.

Chris...

EDIT: 13/6/15. If that link is not behaving, try this one.

Power Point PSS
 
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