Ignition Condenser - Does anyone really understand?

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wr420
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Re: Ignition Condenser - Does anyone really understand?

#16

Post by wr420 »

I'm pretty sure if you charge it with the coil and toss it to someone, and they yell at you.. Its good!
Schwee
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Re: Ignition Condenser - Does anyone really understand?

#17

Post by Schwee »

wr420 wrote:I'm pretty sure if you charge it with the coil and toss it to someone, and they yell at you.. Its good!
Yeah, I've heard that story many times, but I've never seen it work.

Too bad there's really no way for a simple man to test a condenser...
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Re: Ignition Condenser - Does anyone really understand?

#18

Post by Frankenstein »

As John, and others said, the simplest way to test a condenser is to replace it with a known good unit. This may not necessarily be a new one! If you do a change out of condenser with the points during routine maintenance, When all is still working o.k, hang on to the old one, label it for a spare, and use it for testing down the road.
In circuit with the coil and points, it just sits there when the points are closed. As the points open, the coil tries to continue the current flow through the points. The condenser absorbs that current by charging up as the points continue to open. By the time the condenser has fully charged, and will accept no more current,the points have opened far enough that the current can't jump the widened gap, so instead, the majority of the energy that was stored in the collapsing magnetic field in the coil is transferred to the High tension winding, where it jumps the spark plug gaps.
When the points close again, they short out the condenser, draining its charge, so it can start the whole process all over again when the open again.
DD
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Re: Ignition Condenser - Does anyone really understand?

#19

Post by hjans »

Another site where things are explained in an easy way for those of you that want to save money or just want to know...

http://www.classictruckshop.com/clubs/e ... nition.htm" onclick="window.open(this.href);return false;

http://www.smokstak.com/articles/capacitors.html" onclick="window.open(this.href);return false;

But.....again....replacing with known good is best !! ( And cheapest!!)

Hans
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Re: Ignition Condenser - Does anyone really understand?

#20

Post by panz4ever »

Remove condenser. Discharge any residual by touching the positive metal lead to the side of the case.

To test the continuity of a condenser use a VOM set at OHMS (R) x 1K position.

Touch the positive and negative probes together. Use the thumbwheel to align the needle with the red zero.. Hold the red (positive) lead to the case and the black (negative) lead to the positive pugtail of the condenser. Charge the condenser for 3 seconds and then remove the test probles.

Hold the black probe to the case. Watch the needle as the red probe touches ther terminal of the pigtail. The needle should jump from infinity over to 1K and then back down to infinity. This is a measurement of discharge and proves the condensor can hold a charge.

No jump from the needle indicates the condenser is faulty and needs to be replaced.
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Re: Ignition Condenser - Does anyone really understand?

#21

Post by Frankenstein »

Lots of good info frm Hans, John, et all. As many noted, the ohm meter charging/discharge test isn't effective for the small value of capacitance in an ignition condenser.
If it works, leave it in, if your bike's not running right change it.
The replacement is Mexican/chinese and of questionable quality.
An new old stock one sitting on the shelf for 10 or 20 years as probably a better bet than anything currently made.
Essentially, a capacitor is 2 conductors, aluminum foil in this case, separated by an insulator. Mylar film, mica, oil impregnated paper, etc. The closer the 2 conductors (aluminum foil) are to each other, (thinner mylar film), the higher the ability to store charge.( value in Farads, Micro farads, Micro-micro farads).
So, if you've ever opened one up, you see the foil and mylar all rolled up like a cigar inside the can. (Come on, you're a guy, you've never opened up stuff just to see what's inside?) :D
The problem these days, at least one of them, besides using cheap materials, is that they are just basically rolling the stuff up, sticking it in the can, then just jamming the rubber seal/wire on top of the end of the exposed foil, hoping that it will make a good electrical connection between the wire lead and the foil. Well, sometimes it works ok, for a little while, a longer while, but never for a long while!
I think when Detroit stopped buying them by the millions for their use, quality took the long downhill slide to the state we're in today.
About new old stock, the dielectric properties of the insulating materials does degrade with time, but There's a sweet spot in the manufacturing process timeline, where they had immensely improved over what was available in the WWII era to the '60's, to the "make it cheap" era of today.
Ok, realize some of this is fact, some my personal bias, and some speculation, but hey, isn't most life that way?
DD
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