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TR2/3/3A NO spark at points

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pisser

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I all need help ,My tr3 was running great I pulled it in the shop to tune it up New pionts condencer roter cap Set points NO spower to pionts . I have 12v at the wire to Distributor. If i take points off mounting plate with a paper under them not to touch mettle I have power to them as soon as I put the points back down on the plate NO power pionts open or closed All the wires are corect I am thinking it might be the distributor ground wire ? I have now cleaned the mounting plate wating for a new ground wire
 
Thank you so much I did have it wrong I will try that could that have fried my Condencer
No. But don't worry; those condensors (I prefer the modern term, capacitor) will fail without any external help.
 
Thank you so much I did have it wrong I will try that could that have fried my Condencer
I would think not as all the current would be going straight to earth, if it had been left switch on for any length of time, your coil would have fried, that was why i asked in a previous post if your coil was getting hot.
 
No. But don't worry; those condensors (I prefer the modern term, capacitor) will fail without any external help.
And there's no easy way to test a capacitor "in the field" except to replace it with one known to be good.
 
While on the subject of condensers ....Here's where I got mine.
 
We are here to help. Drive it and enjoy the trips.
 
Thank you all its running This might be old age on my part After working on cars since the 60s I could have figured it out
Nice on one pisser, Its nice to know when a plan comes together. I just simplified what all the other posters were trying to explain to you,
There is no I in team.
 
Thank you all its running This might be old age on my part After working on cars since the 60s I could have figured it out

Congrats on the final victory!

What did you do to solve the problem?

Tom M.
 
It Is possible to test a condenser like all capacitors with a volt metre,
Connect the lead of the condenser to the can of the condencer this will discharge it fully.
connect a volt meter set at DC. to the wire and the can, it should read 0.000 if it is fully discharged, after a few seconds it will start counting up 0,001 - 0.002 when it get to 0.010
reverse the leads It should read 0.010 and after a second or two it will start counting back down to 0.000.
when it gets to 0.000 it will again start counting up again.
when it gets to 0.010 reverse the leads again, and it will count down to 0.000
it should also read negative the one way and positive the other.
I hope this little tip will help some of you guys.
 
I'm not sure I understand what you are suggesting, but connecting a voltmeter to a discharged capacitor will just read zero perpetually. Voltmeters don't generate current so they won't charge the capacitor. Or, were you thinking of an ohmmeter?

In any case, the problem with ignition capacitors is that they will seem fine at low voltages but at the high-voltage, high-current use in an ignition system, they will not work right. So, you really can't use a multimeter to test a capacitor in any way that is valid for ignition use.
 
I think you are seeing some effect of static electricity in an electronic voltmeter. I just tried this, and a couple times I seemed to see what you are describing, but when I implemented standard static-electricity precautions, it disappeared.

In the old days of analog multimeters, we could check capacitors by connecting an ohmmeter. The current from the ohmmeter would charge the capacitor causing a drop and then a rise in the resistance indication. But that won't work on an electronic multimeter because the current, when measuring resistance, is too low.

The voltmeters use a field-effect transistor input that puts out a minuscule bias current, something like a nanoamp, often a lot less. You'll never see it in ordinary use.

In any case, if you measure an ignition capacitor with a small current, it will usually test OK, even if it is bad when you use it in an ignition system. I've explored this many times.

I don't mean to be argumentative or play "gotcha," but I keep seeing things posted in forums like this, that just aren't right. Often, they are posted by reputed experts. I think that those of us who understand the issue have a responsibility to speak out when that happens.
 
In any case, if you measure an ignition capacitor with a small current, it will usually test OK, even if it is bad when you use it in an ignition system. I've explored this many times.

I don't mean to be argumentative or play "gotcha," but I keep seeing things posted in forums like this, that just aren't right. Often, they are posted by reputed experts. I think that those of us who understand the issue have a responsibility to speak out when that happens.
And why I posted in #23 above.
 
You can buy a multimeter with a capacitance setting. I picked this Type 130 up many years ago, and it still works! It may have been used to build Apollo 11?!? A standard multimeter gives you an idea if it "may" be good, but it cannot give you the actual capacitance, which is the indicator of whether it is working or not.

 
The instrument repair shop in my Old Fella's lab (Babcock & Wilcox) had a couple of those Tektronix units. Back when Sperry oscilloscopes were part of the Q.C. equation. Not exactly a common tool in most folks' garage!
 
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