Condenser Readings

Cape Codder

Well-known member
Recently there was a thread about checking condensers of which I read with great interest. I have bought the meter suggested in the post. I cannot find the post for the instructions/suggested mf that a condenser should read. Checking thru several pages of posts and using the search, I was unable to get to see what I want.

Can anyone lead me to this Post?
 
Thanks very much Mitch. Just the thread I was looking for. Of course when I search for it I used such things as "Condenser Checking" or "Checking Condenser" to no avail. I didn't know I had to have Tom's name in the search. I will now try to post to that thread again.
Thanks again.
 
The MAIN thing to understand is that the condenser is just a "storage facility" that stores some residual HIGH VOLTAGE in the coil to distributor wire, so it DOESN'T FRY your POINTS!
Bill W.
 
What are you trying to do?

Finding the current value is one thing, but finding out if it works while attached to your car is another. Just because a meter says it is good does not mean it will work in the car.

Your best bet is to purchase or build a coil condenser checker where you can heat stuff up and see it function "in circuit".

For condensers just buy the A&L unit, install it and then forget about it.
 
Well I just checked two condensers with a meter I bought which Mitch showed me where the Tread was "Post #2" (Thanks Mitch)

So the results where the first one is from A&L which I just recently bought (month ago) and was surprised that that it only measured .233 on the 2uf range and 0.23 on the 20uf range.

My second one was from Snyders which measured .222 on the 2uf range and .22 on the 20uf range.

So my question is is the Snyders one shot and is the A&L one on its way out?

I have read MANY times that A&L is the one to buy the condensers from but don't know now. Tom Wesenburg (sp?) had made a statement that with the tester I bought it should be like 0.27uf but I don't know. I can check ohms and volts and that is about it for me.

Last comment is to Mitch/pa I don't understand your post #4.

All I'm trying to do here is rebuild a distributor to the best of my ability and have it work properly with no problems for a long time. I have re-bushed and reamed this distributor, replaced the upper and lower plate, new points and block, new condenser, new distributor body and cap. I also have a new high voltage cable from distributor to coil.

Sorry for the long winded post but like I said I want to do it the best I can.
 
Two of us in our local club have bought the meter. It is a Honeytec A6013L. You can find them on Amazon. They sell for $17. I tested several new condensers purchased from Bratton's. They are the same as A&L sells. They read out at a nominal .243 micro farads.

I have never seen any documentation specifying what the value of an automotive condenser should be.

I believe there is an acceptable range. I tested the one on my car that was purchased from Bratton's years ago and has been in service for years. It measured close to .200 micro farads.

You can test a condenser installed in the car by pulling the fuse and slipping a business card between the points. Put the plus lead on the arm of the points, the negative lead on the ground strap of the condenser.

Tom Endy
 
Well I just checked two condensers with a meter I bought which Mitch showed me where the Tread was "Post #2" (Thanks Mitch)

So the results where the first one is from A&L which I just recently bought (month ago) and was surprised that that it only measured .233 on the 2uf range and 0.23 on the 20uf range.

My second one was from Snyders which measured .222 on the 2uf range and .22 on the 20uf range.

So my question is is the Snyders one shot and is the A&L one on its way out?

I have read MANY times that A&L is the one to buy the condensers from but don't know now. Tom Wesenburg (sp?) had made a statement that with the tester I bought it should be like 0.27uf but I don't know. I can check ohms and volts and that is about it for me.

Last comment is to Mitch/pa I don't understand your post #4.

All I'm trying to do here is rebuild a distributor to the best of my ability and have it work properly with no problems for a long time. I have re-bushed and reamed this distributor, replaced the upper and lower plate, new points and block, new condenser, new distributor body and cap. I also have a new high voltage cable from distributor to coil.

Sorry for the long winded post but like I said I want to do it the best I can.

when i did the search to find you the thread i used the keywords
"condenser tester"
 
I am sorry, but it really is not that important.

They are probably lucky to be +-20% components. It is not like the circuit is a precision radio or something where you need the capacitance be on and stable. My guess if you heat it up to operating temperatures no found on the distributor you will find even more variation.

You need something running around .25uF and a quick look finds common values to be in the .2 to .33uF range.

But the real things you need to know are the Equivalent Series Resistance, ESR, and what happens as the temp goes up. As the temp goes up the value of capacitance can change and it changes more when the capacitor is going bad.

You have to understand the Caps are just 2 thin aluminum foil (well special alloys) with a chemically treated separator. Over time they dry out. While the capacitance may measure correct when cold and with the low voltage of a Cap checker, it will fail with heat and voltage.

So it comes back to, if you want to check a capacitor do it with a coil capacitor tester, not a capacitance checker.
Or
Just get the A&L capacitor which is likely a high temp high quality capacitor that just does not fail easy in the Model A.
 
Mitch - Sorry I'm so slow. Now I got it! Thanks.
Tom Endy, Kevin in NJ and Tom Wesenberg Thanks to all of you for the info. I will be putting it in the car in the a.m.
Tom Endy - By the way Tom I used your writtings for a club presentation on the rebuilding of a distributor. As far as the condenser was concerned I told them they should have a A&L condenser and be done with it. Hope you didn't mind, and sure want to thank you for that.
 
I have read that if a condenser is OVER capacity, the peak will develop on one side of the contact points. If the condenser is UNDER capacity, the peak will develop on the OPPOSITE side of the contact points??
With plugs out & in the dark, look at your points during a loooong continuous crank. If everything's GOOD, you should see a barely discernable, blueish/white spark, which causes points to last a loooong time, & also tells you that your condenser is apparently the correct capacity. Also, IF you see random yellowish flashes FART out of the points, you need to CAREFULLY dress or REPLACE them!
Wonder if anyone makes an adjustable CONDENSER/CAPACITOR, that you could "dial in" to achieve the desired arc at the contact points?
Bill W.
 
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When I was in grade school I made a crystal radio set and made my own capacitor by using aluminum foil and wax paper. It would be fun to do that again and see how many layers of paper and foil it would take to be correct capacity for the Model A.

Even more fun would be to hang it off the coil and actually use it in the ignition circuit.
 
When I was in grade school I made a crystal radio set and made my own capacitor by using aluminum foil and wax paper. It would be fun to do that again and see how many layers of paper and foil it would take to be correct capacity for the Model A.

Even more fun would be to hang it off the coil and actually use it in the ignition circuit.

What about drawing lines on paper with ink to make resistors?
 
When I was in grade school I made a crystal radio set and made my own capacitor by using aluminum foil and wax paper. It would be fun to do that again and see how many layers of paper and foil it would take to be correct capacity for the Model A.

Even more fun would be to hang it off the coil and actually use it in the ignition circuit.
Tom,
I once read, in Readers Digest, of a man stranded in Alaska with a bad condenser. He put 2 sheets of foil in a magazine, separated by 1 magazine page, connected wires to the 2 sheets of foil. Ran 1 to the coil output terminal, & one to a ground. Taped the magazine together tightly, & IT RAN!
Another remote camper got stranded when some water accumulation froze, inside his clear plastic fuel filter on his OLD DATSUN Pickup! SMART MAN, he put the filter UNDER HIS ARMPIT, to thaw it out!
Old Datsuns were NOTORIOUS for breaking throttle cables. One guy carefully inserted some fishing line for a substitute cable. One guy drove 110 miles to our shop, with a long string attached at the carb, through a hole in the firewall & tied a STICK on it, for a HAND THROTTLE!!!
I've seen some WEIRD THINGS!! Even a SNAKE under a hood & one time, a CAT traveled 65 miles, in a cubby hole, behind the headlight of a Jaguar Mark-10! the area was loaded with Pork Chop bones, wonder what that CAT thought, when the Jag blew off its' fan belt?? I rescued the CAT & kept it in the store room until the car owner came back, IT WASN'T EVEN HIS CAT:eek: Our detail guy, Noble, adopted the CAT & named it "TRAVELER":D--(NO, I DON'T "MAKE UP" these STORIES)
Bill W.
 
I have never seen any documentation specifying what the value of an automotive condenser should be.Tom Endy

Reading out of the engine specs for 1955 Ford, 223 I-block 6 cyl, it says condenser capacity is 0.21 - 0.25 microfarads. I am pretty sure that same condenser is used on the 8 cylinder engines and is probably typical for Ford 6volt ignition systems going way back.

Auto parts store should be able to give you specs to be certain.
 
Why not just hook up an ohm meter to test the condenser.
First: disconnect the condenser power lead and touch it to case ground to discharge it.
Second: set multimeter to OHMs. plug in red lead to (+) and connect other end to the power lead. Plug in black lead to (-) and connect other end to condenser mounting bracket.
Third: meter should jump to a high reading, then drop to zero. If it does, it is a good condenser. If it does not, that means it is holding a charge and it needs to be replaced. Try to perform this test while condenser is at normal engine operating temperature
 
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