Testing Echlin FA49 condenser with capacitor tester

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kehughes

Senior Member
I have a couple of questions I was hoping someone could help me out with concerning checking a FA49 condenser with a tester. The condenser will be used on a 6 volt '39 pickup with helmet distributor. The capacitor tester(Sencore) that I have access to is a very nice one that requires voltage, capacitor value, and type of capacitor to be entered. It will check for capacitor value, leakage, and absorption.

What voltage should I set the tester to?

What type of capacitor is this condenser? The options are: 1. aluminum lytics, 2. double layer lytics, 3. tantalum, 4. ceramic, 5. all other caps

Thanks
 
Capacitors is some kind of foil so goes under other category.
You want to test for leakage at up to 500-600v.
You can always increase the voltage in steps.
 
We gave up capacitor testers years ago. Now that replacements are often poor quality, if your vehicle ran well, reusing the condenser is a good choice.
 
kehughes said:
Thanks flathead,

Both that I had tested good.
.34 uf for both with no leakage.
Click to expand...

Put it on continous leakage test and heat the capacitor a bit with a hot air gun..if it passes that it should be good to go.

The old sencores had a tiny screwtype jack on the back that you put between the handle and the button :D simplicity at it´s best.
 
The foil used in automotive ignition condensers is considered a rudimentary film type capacitor with Mylar/PET as the dielectric insulator for the foil strips. Caps usually don't build a lot more than 250 Volts but they should have extra capacity to allow for better oscillation and coil secondary build so they are generally rated for 500 V or more.

A lot of folks use the Echlin IH200 for the old distributors but it depends on the coil you are using.
 
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Those are well suited for a fast check on automotive types since that's what they are set up for. The ones that are made to test a multitude of other different caps can be more complex to operate.
 
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As some of you may know, I am making replacements for the large brass "trash can" condensers that were supplied by Mallory for use with their dual point conversion kits and aftermarket distributors. I'm a "car guy", so all I wanted was a unit that looked good and was super reliable. I enlisted the services of a friend who is an electrical engineer to figure out how to get what I wanted. He dove into it, and we found that the testing and rating of capacitors is quite a complicated subject. In the final analysis, he found that there is a number available from the manufacturers that the average purchaser does not see. It is called "DVDT", and stands for "Delta Voltage"/"Delta Temperature", and it basically represents the variations in voltage and temperature that a capacitor can go through before it fails. Obviously, the higher this number , the more reliable the capacitor is under severe duty, which automotive use certainly qualifies as. "Flatheadmurre" referred to using heat while doing the testing of any capacitor, which is an important component in capacitor performance. If it is possible to get the "DVDT" rating from the manufacturer, it is a better indicator of capacitor capability and quality than any tester can give. From our research, most automotive condensers have a "DVDT" rating of 200-800.
 
Yep temp is very important. Many times a customer will walk in and say this runs good cold and either dies or misses when hot. I will put the distributor in a test machine and hook it up. Once running it show a steady firing of all eight cylinders, then i have a large Grainger heat gun next to the machine, i start blowing hot air on the distributor base and condensor. Many fail and then run on 4-6 cylinders........:(
 
Re: Testing Echlin FA49 condenser with capacitor tester - correction

I talked to my partner last night and found I made a mistake in my previous post. The "T" in "DV/DT" stands for "time", not "temperature". It as a combined measurement of the size and duration of voltage spikes that the capacitor can withstand. But again, the higher the number the better. Capacitors are rated separately as to temperature. I am just the "car guy" in this and as such, no electronics expert.

The problem we are facing is that as the quality of the capacitor goes up, the physical size goes up. Also, the physical size of the capacitor increases with the capacitance. There are any number of .22 or .33 mfd capacitors available that would fit into our packaging, but they would not be robust enough to withstand the rigors of automotive use. At this point, we are using a .22 mfd unit with a "DVDT" of 2200 and a temperature tolerance of 250 degrees centigrade. We have not yet found a .33 mfd that meets these stringent specifications that will fit in our packaging. We are looking, though.
 
Are you all using a Mylar film type or one of the more recent caps that are used more for solid state board design? I've see later more exotic types used in magnetos like the rotating armature K2F types and they definitely last longer than the old Lucas types. Just curious.
 
after reading these posts i did some testing with my Sun Master Motor Tester on several nors. condensers and a new FA49. tests are for resistance,capacity and leakage. all the nors. ones showed low capacity,less than .30 and most showed leakage. i thought the tester was not correct until i tested the FA49 which showed no leakage and .35 mfd. so, dont buy any old stock condensers as your chances of getting a good one are slim.
 
The old ones could have wax paper for a dielectric but some manufacturers used mica. The paper ones only last as long as the paper and they don't like heat much. The later mylar (polyester) ones are better but they don't always have very good quality control with the lead connections or the foil so many of the new ones are crap right out of the box. Manufacturers of these products just really don't care if they work or not. Echlin was a quality manufacturer when they had their own system but now that they are part of Standard Motor Products, their future quality is not as crystal clear as it used to be.
 
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