Discontinuing search for .33 micro-farad capacitors.

About 60 years ago I read an article on ignition systems that said that the entire electrical circuit comes in to play when trying to determine the resonance of the circuit. Long story short is it said if the points are wearing evenly do not change the capacitor.
 
As an electrical engineer I can assure you the MFD rating on the Cap can be out by a sizable amount. Buy a good (Fluke) meter that has the MFD capability and check them, the differences will surprise you...
 
As an electrical engineer I can assure you the MFD rating on the Cap can be out by a sizable amount. Buy a good (Fluke) meter that has the MFD capability and check them, the differences will surprise you...

My partner is an experienced electrical engineer and does have such a meter. Surprisingly, the condensers we have checked are usually pretty consistent, unless they are shot. We check each of the capacitors we use when they come in and when they go out, and they are usually within .01-.02 micro-farads. They should be, because we buy the best we can find. The point here (which your statement seems to confirm) is that automotive ignitions seem be able to tolerate a large variance in capacitance and still operate successfully. a secondary point is that it appears that higher capacitances (in the thirties) are not required by any coils other than original Ford integral style coils, which are becoming as rare as hen's teeth.
 
About 15 yrs. ago, I moved the condenser up to the coil on my 42. I was told that the mfd. would be less at the points due to the increaseng of the coil to dist. wire. Checked with Std. Ignition as to what the microfarads was. They stated they were 0.33. and due to increased length of wire would drop about .02 to-0.03.
Anyway it has worked for me as replacing a cond. on the road is no fun.
If Oldford is looking at this, he can say if he has had problems as he followed
what I did. He drives a lot more than me.
The condenser is Std. Blue streak AL111X and the ones I have were made in USA. I believe they were used on early 80's Mopars.
 
A Fluke multimeter will give an accurate mfd reading on an automotive type condenser. But to test an automotive ignition condenser correctly then purpose made testers were available in the past but a bit hard to find today. The tests required are the micro farad rating, leakage or leak down with 400 to 600 volts applied and then series resistance. The multimeter tests described in other posts in the past are only very basic tests. Condensers should be warmed up to an equivalent temperature when mounted on the engine and tested . Mr tubman you should have a tester like this if you are really going to test and sell condensers. I have original 1934 Fords and have had trouble with original Ford condensers as well as the reproduction ones to the point you never know when they are going to pack up. I have original Ford coils on my cars. I now use a modern .28 mfd condenser which works very well and I have fitted a few of these to other makes of cars and even a British motorcycle which has coil and distributer ignition. I have not driven my 34 for a lot of miles for a good test, but it starts well and runs perfectly as a good old V8 should. The distributer contacts still look very good. I have been an auto electrician for nearly 60 years so have some experience in this equipment. A .28 mfd condenser would seem to be a good range option for many applications rather than the low .22 to .24 ones that seem to be the normal rating on new condensers today. Regards, Kevin.
 
A Fluke multimeter will give an accurate mfd reading on an automotive type condenser. But to test an automotive ignition condenser correctly then purpose made testers were available in the past but a bit hard to find today. The tests required are the micro farad rating, leakage or leak down with 400 to 600 volts applied and then series resistance. The multimeter tests described in other posts in the past are only very basic tests. Condensers should be warmed up to an equivalent temperature when mounted on the engine and tested . Mr tubman you should have a tester like this if you are really going to test and sell condensers. I have original 1934 Fords and have had trouble with original Ford condensers as well as the reproduction ones to the point you never know when they are going to pack up. I have original Ford coils on my cars. I now use a modern .28 mfd condenser which works very well and I have fitted a few of these to other makes of cars and even a British motorcycle which has coil and distributer ignition. I have not driven my 34 for a lot of miles for a good test, but it starts well and runs perfectly as a good old V8 should. The distributer contacts still look very good. I have been an auto electrician for nearly 60 years so have some experience in this equipment. A .28 mfd condenser would seem to be a good range option for many applications rather than the low .22 to .24 ones that seem to be the normal rating on new condensers today. Regards, Kevin.

My partner in this venture is an accomplished EE and has this and more. I really don't appreciate your condescending post. I might value your opinion more if you could spell "distributor" correctly.
 
About 60 years ago I read an article on ignition systems that said that the entire electrical circuit comes in to play when trying to determine the resonance of the circuit. Long story short is it said if the points are wearing evenly do not change the capacitor.

Yep thats the way o was taught in the old gas station tune up days , remove the points if they look good replace them and leave the condensor in place :eek::eek:...
Same with $9.95 alignments test drive the car and put on alignment machine , if all parts are gopod , test drive was good and tires arnt worn , spray with wd40 and ship it !!!!
Same with carb adjustment turn screw in two turns and out two turns charge them a $1.00 and ship it .
Timing listen to starter , snap throttle both sounds ok ship it !!

attached is a photo of the old ESSO station , from town newspaper..... been there for many years , still in business today....pic is from the early 60,s

REAL WORLD FIXES 101 !!!!!!
 

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If you are interested, there is a fairly detailed article on condensers in the 2014 September/October issue of the V-8 Times.It covers the values of Ford condensers from 1928 thru 1953.

This article by Frank Scheidt is a pretty good one to read. He covers all the bases of testing including the fact that a person needs to know the inductance value of the coil that is in the mix where there is no value available from Ford. Skip Haney may not know the inductance value of his coils after overhaul with new materials either. It's not something a lot of people think about. The conclusion that Frank and a friend with a background in electronics came to was that a good overall condenser value for the original design early V8s would be 0.25 mfd. He admitted though that he was going to continue testing on that value and see how it goes. This was in late 2014. I wonder how his testing has done so far. They tested with very low value to very high value capacitors and it's interesting some of the descriptions about how that went.
 
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Not to nitpick or know. Some have served a lot of people well. Appreciate all the information.
 
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