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Discussion Starter #1
I'm trying to get my 1966 289 started and I have a little problem... no spark!

I tested for spark by taking the plug that connects the coil to the distributor cap and held it to the exhaust manifold and I turned the key. The engine turns but no spark. So... I replaced the coil and still no spark.

Last night I used a test light to check for power. I have power on + side (larger left bolt) of the starter relay and on the right side smaller front plug on the starter relay. I have power to the + plug that connects to the + side of the coil. When I use the test light it also lights up when I hold it to the negative screw of the coil (this plugs into the distributor).

Why no spark?

Thanks in advance.
 

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Is your manifold very rusted or painted? Make sure the plug has a good ground. Are the points in good shape and adjusted correctly? Plug wires in good condition? Did you change something since the engine last ran?
 

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Discussion Starter #3
Manifold is a little rusty. How else can I test for spark?

I haven't touched the points in years. I thought I would still get a spark from the coil whether the points are good or bad. Is that wrong? Does the ground wire go from the coil to the distributor? If it is, it looks like its in good shape.
 

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check all the (-) coming in, like the points and the condenser, i had a little grounding problem at the wire from the condenser in the distributer, have a look. you need the neg/ground, for it to spark as well as the pos. make sure that your points are clean and touching.
good luck!
 

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No Juice From Coil

Hello mrstangABQ,
OK..
Let's review a few things.
1. we know the car has juice running into the battery side of coil.
2. - Now there is another small post on the coil. That post is marked
DIST. - This for the small wire that runs to the distributor.

BE CAREFUL with the following.
1. - Pull the center (ignition wire) thick like a spark plug wire from the top of the distributor.
2. - Hold the wire with insulated pliers (plastic or rubber handles) Use caution
3.- Keep other end of this wire in the center of the new coil.
Now hold the end that came from the distributor cap about 1/4 inch from the cap (where it came from).. You must be able to see the metal end opf the coil wire you are holding.
4. - Have someone crank the car....you should see a spark jump from the wire you are holding back into the center post of the cap.

You should see a spark jump....if you don't.

5. - Shut off key..... Open distributor cap.

Now look at my picture.........
AGAIN USE CAution - high voltage from coil and or capacitor.

Put the key to the on position
6. - Place a screwdriver where I have marked A. I want you to put the screwdriver tip between the points arm and the lobe of the distributor. Make sure screwdriver is insullated and/or wear gloves.
7. - Now twist the screwdriver so that area B of the picture opens.

Do you see a spark there?

if you don't then you have one of the following
A. Bad points, capacitor (labelled C in pix), bad cap or bad coil wire (Large center one.

If you have juice going into the coil like you do and no spark at the center post of the distributor it is one of the above.

Look under the cap at the center carbon tip that hits the rotor...how does it look?
Is it pitted, cracked or anything like that?

If you are unsure of what the problem is from there, I would replace all of the items.
POINTS, Cap, capacitor, rotor and ignition wires. It is possible just the coil wire is fried but I would change all the plug wires if they are more than a year old.

I am posting this here to try and help others as well.

Please try these suggestions and post back or PM me. Unlikely you got bad coil but it could happen...not often though....... Print dad
 

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Discussion Starter #6
I tried the first suggestion (hold center coil wire to distributor)… no spark.

Then I tried suggestion two. This time I got a spark at the points by putting my screwdriver between the points arm. I don’t know what that means but I got a spark there.

I also tried taking the + end of the wire that plugs into the coil and holding it close to the positive post on the coil to see if I got a spark there... still nothing.

There’s a new thread with another guy who doesn't have a spark at the coil. He was told to check the voltage regulator. How do I check that?

Thanks
 

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I tried the first suggestion (hold center coil wire to distributor)… no spark.
[w do I check that?[/FONT][/COLOR]

Thanks

Hello,
I am trying to get a little extra help from Veronica.
But what I think we have is this:
1. - You are getting juice to the coil or you wouldn't have juice at the points.

On the coil, even though it is marked (-) that wire is still a positive wire.
Ford originally marked the coil...BAT and DIST.
Aftermarket ones often use (-).

Be sure the points are opening when you rotate the motor. If I understand the way it works, the points are acting as a switch to allow the coil to build up a charge.
The coil sends the juice thru the center post of the coil to the center of the cap. Then from there it goes to the rotor and that sends the juice to the correct plug wire.

To me I think if the points are moving you problem must be;
1. - Bad Cap
2. - Bad rotor
3. - Bad Coil (big) wire
4. - Points and /or condensor.

let's see what the "Goddess of Wires has to say.

Thanks Veronica........Print Dad
 

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Hello. :) You are too kind, Jim. There are a lot of people that are thoroughly familiar with the wiring of these cars. I've just been fortunate enough to be around some of them. :)

Here is how a breaker point ignition system works. The ignition system has two separate circuits in it. One, called the primary circuit, consists of the primary windings in the coil, the primary lead, which is the wire that runs from the Dist post on the coil to the distributor, the points, and then a path to ground through the casing of the distributor.
The secondary circuit is the secondary windings of the coil, the high tension lead ( ninth spark plug wire that goes to the distributor cap), the distributor cap, rotor, and the plug wires. There are two different circuits inside the coil. How this works is power is supplied to the coil through the post marked Bat. When the key is in the 'Start' position power goes out to the starter solenoid through the wire attached to the S post on the solenoid. This closes the switch inside and sends power to the starter, and sends power out through the wire on the 'I' post on the solenoid, which meets up with the wire that goes to the bat post on the coil. Power goes into the coil, runs through the primary windings, out the Dist post on the coil, through the closed points, and then to ground. When the car starts and the key is in the 'On' position, power goes through the resistor wire plugged into the ignition switch connector, and out to the Bat post on the coil and, again, through the primary circuit.
When the points open, that breaks the primary circuit, (hence the name 'Breaker Point Ignition' :gringreen ) and the magnetic field that is built up in the primary coil windings goes through the secondary windings in the coil, and this produces the high voltage needed to actually fire the spark plugs. The high voltage goes out of the coil through the high tension lead, down into the distributor cap, through the rotor and out to the spark plugs, which are grounded through the threaded part of the plug. The points then close, which allows the current to pass through the path to ground through the primary circuit, and the coil builds up another shot of the high voltage for when the points open again.

So, if the points are good, you will see a power reading from pretty much any metal part of the distributor when the points are closed, because the distributor is the ground for the primary circuit. If there is no power reading from the metal of the distributor, that means that power could not pass through the two contacts of the points, and that can't happen if the points are in a usable condition. Power makes it to one contact, but doesn't make it to the other = points are no good.

If you have a power reading on the metal parts of the distributor when the points are open, that means that the primary lead is shorting itself out on the case of the distributor somehow, probably where it goes through that hole in the side of the distributor. The fix is to replace the primary lead and try not to scrape it up when it gets shoved through the hole in the side of the distributor. :D

If the primary circuit checks out ok, but the plugs still aren't getting any spark, that is generally either a torched out distributor cap or rotor, bad plug wires or spark plugs that are fouled or just plain worn out.

It's actually a pretty simple system once one understands how these components all work together to shoot sparks down to the plugs. :)
 

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No Juice From Coil

Hello Veronica,
Gotta get this going. I think i have a better understanding thanks to your help.
I am assuming his trouble is in the carp, rotor or points and i correct.

I also see you have been busy on the forums....Thanks form all of us.

Print Dad
 

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Hi again. :) That's very sweet of you, Jim. :) There are lots of people here that know plenty. This is a team sport, much like life. :)
 

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No Juice From Coil

hello Veronica,
Bottom line..... if he has juice at the points, does it mean his problem is
bad points, cap, rotor or a bad coil ignition wire (9th wire). Thanks..Print dad
 

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Hi again. :) If he takes a volt meter and puts the negative probe on the negative battery post, and the positive probe on the plate that the points are attached to, he should get a power reading when the points are closed and nothing when the points are open. If this is in fact what he is getting, and the point gap/dwell angle are set correctly, then the points are not the problem. If the primary circuit ( points, etc..) is functioning just like it's supposed to, and he still has no spark at the plugs, then his problem is somewhere between the hole in the middle of the coil where the high tension lead is plugged in and the tip of the spark plugs. He should remove a convenient spark plug, ground it out on something with the wire attached, have someone else crank the motor and see if he has spark at the tip of the plug. If no, he should remove the plug from the wire and repeat that experiment with the positive lead of his volt meter making contact with the plug inside the end of the spark plug wire and the negative lead on a valve cover bolt or something. If still no, remove that wire from the distributor cap and repeat, with the positive lead inside the cap where the wire makes contact. If still no, remove the high tension lead from the coil and repeat, etc... Start closing in on the offending component from both ends.

The short version of the answer would be, if the primary circuit is functioning correctly and the coil is known to be good, then the problem is probably the cap, rotor, spark plug wires or spark plugs, pretty much in that order. :)

If it turns out that he actually has spark when he grounds out the plug and has someone crank the motor, that's kind of a whole different sort of problem, probably with the fuel induction system. :)
 

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Discussion Starter #14
Bingo!

I replaced the cap, wires, rotor, condenser and points and she started right up.

I think the main cause of my problems were wires and points. As soon as I connected new wires and cap I saw spark for the first time. At this point the car wanted to start but couldn't. After I replaced the points, condenser and rotor she fired right up!

Thank you so much for all of your time and great information. After 6 years its a great feeling to have her running again.

Now on to making her run right!

Cheers to all!
 

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I currently have a thread going called "1966 inline 6 electrical issues", but I found this similiar thread because I'm having the same problems with my car not starting. Heres what I've done so far without success;
new points, condensor, rotor, cap, plug wires and plugs.

Then I put the neg probe of a voltmeter on the neg battery post and the pos probe on the dizzy plate like Veronica suggested and there is nothing, no juice.

I then did as Print Dad suggested and Pulled the center wire from the top of the distributor, held the wire with insulated pliers. Then I held the end that came from the distributor cap about 1/4 inch from the cap while the car was cranking and there was no spark.

Next I put the key to the on position, placed a screwdriver between the points arn abd the lobe of the distributor, twisted the screwdriver so that points open and there is no spark.

The voltmeter shows 12.6 volts at the battery, the same at the solenoid. With the key in the on position I got 6v at the coil. I recently put a flamethrower coil in, so I put the old coil on to see if that was the problem and the old coil is the same 6v.

COMPLETELY STUMPED.
 

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1964 1/2 289 single points. Put in new Cap, rotor, condensor, points, spark plug wires, spark plugs, voltage regulator and coil. Put a timing light on number one, three,seven and eight wire got no light flash. Put it on wire 2,4,5 and 6 and got a light flash on timing light. what would cause those not to get fire?
 
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