Point gap

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RandyB said:
Thanks for your support bud!
I’m not giving up on it it will be a nice ride
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OK here is "next." You need a a multimeter and a 12V test lamp. Remove dist cap and bump engine so points are CLOSED, on flat of dist. cam. Turn key to "run" and measure voltage at coil+ It should be about between 6--10V or so, but not higher. If it measures 12V then the points are not making contact or are not closed. Now measure coil NEG. Voltage should be very low, not more than 1V at most. If more it shows points are not closed or are not making contact

Now (turn key off) and bump engine so points are on high point of cam. Now measure coil+ voltage, it should be higher, "same as battery" or about 12--12.6V If it is still low, "you screwed up" hooking up the points/ condenser/ dist primary wire, and something in the dist. is shorted to ground.

If you get NO voltage at the coil + then you have likely burned out the ballast resistor. Probe up there and see if anything is "hot" with the key "in run."

If tests above seem OK, "rig" a test gap out of the coil tower like a plug and jack it up so you can see it while operating the key. Crank the engine USING THE KEY. You should get a nice hot blue snappy spark, at least 3/8" long and more often about 1/2" long
 
A Body 440 WHY NOT said:
No spark ?
Ok
Start systematically at the beginning and work your way thru the ignition system. It’s not that bad. If you jump around it will drive ya nuts
Start at the ballast resistor on the firewall and work forward from there
You have 12 volts TO the Dist ?
( could be a connection that got missed)
With a test light check power at the coil while cranking.
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Will start at the top tomorrow buddy!!
Any other things you can help me out with please list them
Yes, I’m going nuts. This is nothing like my 72 slant6 lol
Got to be up early tomorrow so time to hit the rack and think of things I might of missed
 
If you have a good test light, make sure you have power to the + side of the coil. The with the points open, make sure you have power to the points/condenser terminal inside the distributor. If you do, take the coil wire out of the distributor cap and lay the end about a 1/4" from a good ground on the intake. run a screwdriver (with an insulated handle!) across the distributor case to the contact end of the points, in essence, shorting the circuit to ground. That should create a spark at the end of the coil wire if you make and break that connection, the same way it would if the points were opening and closing. If that works to create a spark, you have something wrong with the points or condenser. If it still doesn't create a spark, you may have a bad connection (or it's wired wrong) at the points/condenser connection. If you don't have power to the coil, check back the circuit until you find power. Might be the ballast resistor or a wire connection up the line somewhere.
 
AJ/FormS said:
It will run at just about any gap, as long as the points actually close and actually open.
The specified gap is for new points in a new distributor, and is used to ballpark the dwell. The dwell is the thing that your coil is looking for.
Dwell is the time in degrees that the points are closed, causing a charge to build up inside the coil. When the points open, the coil fires it into the coilwire, to be distributed . The more dwell a system can generate the better, but there is a point that more is not necessarily useful. The coil works best, over a broad range of rpms, at the specified dwell, created by the specified pointgap.
That don't mean that it won't work at any other point gap.......
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You have it right. I had a brain fart for about 55 minutes and 10 seconds.
 
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Jadaharabi said:
I think you have this backward it is the time that the points are open that allows the coil to build up energy in the condenser. As soon as the points close the field collapses causing the spark.
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Nope. Dwell is the amount of time in distributor degrees that the points stay closed thus charging the primary windings in the coil. As soon as the points open (break) the coil discharges through the coil wire to the cap, rotor, and to the individual plug wire.
 
toolmanmike said:
Nope. Dwell is the amount of time in distributor degrees that the points stay closed thus charging the primary windings in the coil. As soon as the points open (break) the coil discharges through the coil wire to the cap, rotor, and to the individual plug wire.
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Correct, and furthermore, the reason for dual points systems is to create longer dwell time (points closed). You can not just "under gap" single points to create more dwell, because one, there is less wear "room" before the points wear shut and stop running, and two, longer dwell on single points causes them to burn because they don't open rapidly enough on the cam "rise." Single points typically have 30* dwell for V8, dual points typically 40-42 or so
 
67Dart273 said:
Correct, and furthermore, the reason for dual points systems is to create longer dwell time (points closed). You can not just "under gap" single points to create more dwell, because one, there is less wear "room" before the points wear shut and stop running, and two, longer dwell on single points causes them to burn because they don't open rapidly enough on the cam "rise." Single points typically have 30* dwell for V8, dual points typically 40-42 or so
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67Dart273 said:
Also to the OP set point gap/ dwell FIRST and set timing LAST
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Smart guy. Yes. One point set makes contact and the other set breaks that contact. The 2 sets are spread apart a few degrees to make that happen. My old Tech school teacher always said, dwell effects timing but timing doesn't effect dwell.
 
RandyB said:
Did that Sir and still no fire.
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Pup the cap off. Pull off the rotor. Position the distributor shaft so the points are open. Now reach in with a flat blade screwdriver and bridge the gap between the points. Do you get a spark?
 
Is the D in correctly? ; you said you took it out.

The point-system is pretty primitive. It only needs battery power to the coil (+) terminal, and a switching mechanism on the (-) side.
And the condenser cleans it up.

A simple switch I have used to prove the coil is working, is a coarse file commonly known as a flat-bastard, and some wire. I remove both wires from the coil, near-ground the coil hi-tension wire, and jumper the battery(+) to the coil(+).. Then I lay the file on a good ground, connect a second jumper to the coil (-) and strip about 3/8 of an inch off the free end. I then drag the bared wire along the file, while watching the sparks stream from the near-grounded wire.
If you get the spark-stream, the coil is good.
From here, you can re-install the factory power source, turn the key to run, and drag the bare wire along the file again.If you still get the spark-stream, then the factory power source is good.
So now you are down to the switch mechanism. Reinstall the point wire onto the coil (-), separate the points, and jumper the point arm with your bared-end jumper, then drag it along the grounded file again. A spark-stream now proves the condenser is working and the points are not grounded.
Remove the jumper. Short the point arm to ground (as previously mentioned), by using a small screwdriver in a stabbing motion, quickly making and breaking the connection. Every time you stab, you should get one spark. You now have a fully functioning system, with several caveats;
1) the points have to be clean on their contacting surfaces.
2) they have to actually open and close, and
3) the distributor driveshaft has to be in sync with the camshaft, and
4) in order to run, the spark has to make it out of the cap, and be sent to the right sparkplug at the right time, ie, the rotor needs to be installed and indexed., and
with the #1 cylinder (frontmost on the crank/ driver's side front) at TDC/ COMPRESSION, it's wire synced to whichever tower is standing above the indexed rotor-tip, and the others following in the correct firing order, namely 18436572.

That's all I got.
 
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Big thing with the "new" parts are they are crap. Disconnect the condenser and the lead, check with the points open that the arm is not grounded then when closed they ae grounded. Also check that the condenser is not shorted when it is off the points. 28-32 is the dwell setting on most single point mopars. Hope it helps.
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I’m at work now but will review everything that you kind people have taken your time to respond with. I did some of this back in the 70’s, but for those that remember those times,,, well,,
Thanks again, I’ll keep you informed on my ‘progress’
 
halifaxhops said:
Cheasy but explains it.
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AAAAAAAAAAAAaaaaaaarrrrrrrrrrrrrrrrrrrrrrgggggggggggggggggggghhhhhhhhhhhhhhh!!!

Why is he sticking a greasy screwdriver between the points contacts at the end of the video??

LOLOL
 
krazykuda said:
Who carries match books around any more??? :rolleyes:
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No kidding. A hundred years ago, a worn out solid silver dime would work. You had to be careful not to drip wax into the distributer when illuminating with a candle though. :D
 
My 73 Challengers were the only old cars I had with electronic ignition. All the rest were points. I don't remember ever having issues. Not knowing what was under the hood when you buy a used car I usually put quality tune up parts in right away. I still use the same quality parts and they last and work well.
 
toolmanmike said:
My 73 Challengers were the only old cars I had with electronic ignition. All the rest were points. I don't remember ever having issues. Not knowing what was under the hood when you buy a used car I usually put quality tune up parts in right away. I still use the same quality parts and they last and work well.
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back in the day we had a 73 challenger in the family. That had points. I did change them over to electronic.
 
Duggie said:
No kidding. A hundred years ago, a worn out solid silver dime would work. You had to be careful not to drip wax into the distributer when illuminating with a candle though. :D
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Aw c'mon!! If you can't do this by feel in complete darkness you ain't a mechanic!! LOLOL
 
67Dart273 said:
Aw c'mon!! If you can't do this by feel in complete darkness you ain't a mechanic!! LOLOL
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As long as they are closed when you are on the flat side of the cam it will run. I can eyeball .015 and I bet you can too.
 
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