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Ignition condenser/capacitor post mortem

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I too had a bad capicator from our main catalog source ( the main lead wire was not connected within). I was able to get the same capicator from NAPA so it is a readily avialable item it just takes some doing when things go wrong.

So for the cost conscious points and condenser are still a good for the most part reliable solution.

Mark
 
So has anyone looked at the alternative electronic ignition that Peter C, has been selling. He has a buddy who got tired of ignition issues with Kohler engines on small tractors. He developed an electronic trigger that retains the points but the points now switch 12 volts on/off instead of 20,000 volts. He's already developed everything for the Lucas Distributor and it fits under the cap. $50.00 including postage from Peter C. Is this an alternative to the capacitor issues we're going through? I know Peter C, has had one of these setups with the same point I believe in his Mini for almost 50,000 reliable miles.
 
My iss ue ain't so much with where th' parts come from (tho I'd trust Peter's parts to the end of the earth, for sure), but rather that I sincerely trust POINTS and condenser for more robust reliability in the long run.
 
That's why this solution that Peter C has is quite interesting. Points now switch low voltage instead of 20,000+ volts and this uses some sort of solid state electronic trigger. All fits under the cap. Peter C. refers to is as a Transcondenser. I had a link to the guy's web site and cannot find it anymore. According to Peter after 50,000 miles on his Mini, points are not pitted but still shiny and look like new. Petronix seem to scare me. Lots of people who have had issues but breakdowns for lots of unexplained reason. And at the same time lots who swear by them.
 
So with Peter's system, you could quickly stick in a condenser (and switch a few wires) if the electronics of his gizmo failed?
 
What you describe sounds a lot like the original "transistor ignitions." These were simply an electronic device where the points cut the current to a transistor, and the transistor operated the current to the coil. That way, the points handled a very small current and at a low voltage. This extended the life of the points, but they still had to be replaced periodically because of rubbing-block wear. Probably less subject to problems from contamination, too.

By the way, I wrote up a section on ignition systems for the Wiki; its under "General Technical Articles." There is a link to an ignition circuit based on this idea. You can build it with a handful of parts. It does require the capacitor, though. If it fails, you just throw one switch, and you're back to conventional ignition.

I will add one point about reliability: electronic devices at their worst are much more reliable than electromechanical ones at their best. That's a simple fact, and the reason why I use an electronic ignition system (I use a Crane). If you're really worried about an electronic ignition module failing, you can carry a spare for under $100, and it's much easier to replace than a set of points. As for me, I don't worry about the ignition module; there are 100 things that could go wrong that are WAY more likely than the module failing. I'll take my chances.
 
Steve, did you ever determine a good suppler for condensers.
 
Jim_Gruber said:
He developed an electronic trigger that retains the points but the points now switch 12 volts on/off instead of 20,000 volts.
Click to expand...


Huh ?

From what I've always understood, the points only see a max of 12v to begin with. It's the secondard side that carries the high voltage.
 
When they "break" it hits higher voltage.
 
DrEntropy said:
When they "break" it hits higher voltage.
Click to expand...

Yeah, but from what I understand, only on the secondary side. I've never heard of high voltage being produced on the primary, especially with an open circut.

Are you saying high voltage is being produced on both sides?
 
A coil has to discharge and will through the air or whatever when power is removed. If the 12v is removed and there is a good ground on the high side then it can really knock you good at the low side. I don't know what the voltage gets up to but it is higher than 12v. The condenser saves the points from sparking and more or less doubles the input voltage at the coil when the points open.
 
I know the condenser can give you a good jolt. We used to charge 'em up with the starter tester then toss them to the new guy.


The only thing I know for sure about elecetricy I learned as a child.


That would be: Do not, under ANY circumstances...shove the chrome plated plastic tweezers from the "Opperation" game into the wall outlet...
 
To accurately test a condenser, you need to check Microfarads, AND the rate of charge/discharge. I find that most failures aren't necessarily because of the cheap design, but because of a poor ground, either in the distributor or between the distributor/engine, or engine/chassis. Overheating because of a bad ground causes failure.

The condensers you have are all of poor design. The best I'v efound are from Standard Ignition, part # Lu-206. They are sold under other part numbers and brands, reboxed by Napa as well as others. The key is the black wire and an offset small hole for the condenser screw - NOT a slot for the screw.

I have been using a condenser I have made (exclusively per my order) with very good results. I have sold hundreds with no failures reported, like the red ignition rotors I've sold over 55,000 of in the last few years. A solid track record by not redesigning the original, but bringing back the quality of the original. Its not rocket science, and there's no reason to reinvent the wheel, although if there were a better option I'd adopt it!!!

The reason I went from the best condensers on the market to the 2nd best is merely the ability to keep them in stock as well as cost. I can give these away for free with rebuilds instead of charging $8, and they have a virtually equal track record.
 
I have one of these Velleman transistor kits on my '63 SAAB. I also had one on my '47 Chevy PU modified for 6v. They use the points as a switch only and do away with the arcing and pitting . The condenser is also disconnected. There is still the chance for wear on the rubbing block so the gap has to be checked to keep the timing correct. Very easy to build and install and also easy to switch back to the stock configuration.
https://www.arcade-electronics.com/detail.aspx?ID=17654

Bill
 
Interesting, but not quite sure what the judges would say about that.
 
"Gives your car the feel of an expensive luxury car"

O.k, so it'll make vinyl feel like leather, are my seats heated now too?

I guess it all depends where you mount it. :laugh:
 
I'm a little surprised to see this thread resurrected. A couple comments:

Yes, the capacitors I dissected were bad quality; that's the point. They were the kind of thing people were buying and having problems with, so those are the ones I looked at. The point was to try to figure out why these seemed to be failing. They clearly failed because of a bad internal ground, something I wouldn't have expected. So, I'd say that these did indeed fail because of poor design. Of course, a bad external ground could cause problems too, but that's not a capacitor failure.

Also, regarding, "overheating because of a bad ground causes failure." What kind of failure OF THE CAPACITOR, resulting from overheating, are we talking about? In the capacitors I examined, the capacitor puck itself hadn't failed, it just lost good contact with the inside of the can because of burned contacts.

Finally, to clear up a point--the capacitance (microfarads) of a capacitor is either right or wrong at the outset; it won't change in use. Its charging rate depends on its current ONLY--charge is the integral of current over time. The rate of rise of the voltage, if that's what you mean by charging rate, is the current divided by the capacitance. It's not an inherent property of the capacitor. The only way this will change is if there is some significant resistance in series with it, such as caused by burned internal contacts. Maybe that's what you're measuring when you check rate of charge--presumably you're using some kind of standard tester?

I'm glad there is a source of good ones, but apparently most people, myself included, are not aware of this, or know where to get them. I think that the option of using a general-purpose electronic capacitor is a perfectly valid one, as it totally avoids the problems I identified, is easy to obtain, and will last virtually forever.
 
Regarding the Velleman kit--this is the same approach used by early "transitor ignitions," and yes, you don't need the capacitor across the points. You do need a fairly large one in the circuit, though (the yellow thing in the foreground of the picture, between the board and the heat sink). In essence, it uses a transistor instead of the points as a switch, and the points work as a low-current switch that triggers the transistor. The idea worked pretty well. Not as good as a CD ignition, but still pretty good.
 
Somehow when you explain it Steve I get it. Thanks.
 
The second to last new condenser I had lasted 20 miles. The last one was still working when Jeff converted my dizzy to a Pertronics system about 40,000 miles ago.

This is my TR6. When I finally get my Midget running it too will be converted to a Pertronics.
 
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