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No Spark?

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Old 02-03-2008, 05:46 PM
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No Spark?

Yup- still working on the the 68 half cab with a 200 I6. I have replaced pretty much everything I could, battery, voltage reg, starter, selinoid, carb, fuel pump, cap, points, rotor, plugs, coil, plug wires. The motor turns at normal speed, but when I remove the high tension lead off the dist and hold it close to ground- NO SPARK? Did I hook up the coil right? Positive to wiring harness, negative to dist? Could the coil be bad right out of the box? If not the coil what other possibilities could I test?
 
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Old 02-03-2008, 09:58 PM
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Do you have power to the coil +? Check for power and then check the negative side while someone cranks the engine to check for a pulse which will indicate whether the points are working properly.

Jason
 
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Old 02-04-2008, 07:06 AM
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I will give it a try, thanks- if no power to the positive side- where do I go from there? If power to + but no negative- does that mean the coil is bad?
 
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Old 02-04-2008, 09:36 AM
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Power to pos side is from the ignition switch. The points in the dist control the spark to plugs. If you have power on + side of coil and no pulsing on - side of coil, trouble is probably in distributor. The coil raises the 12v pulses to 25000 volts and distributor rotor sends it to appropriate plug to be fired. To check secondary side of coil which is the - side with an ohmeter on scale to read between 4000-10000 ohms put one lead on - of coil and other lead in coil wire tower of coil. This is done with no power to coil as the battery in volt/ohm meter supplies the power. If the reading is within above range(except hi perf coil),then coil secondary windings are ok.
 
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Old 02-04-2008, 10:22 AM
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If you have no power to the +, you need to trace back to the ign switch. The circuit has a resistance wire to reduce the voltage to the primary side to prolong the life of the points.

If you have no power to the - side, you could have an open coil winding. If you are not getting a flash, the points may be set wrong or a bad connection.

Jason
 
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Old 02-04-2008, 11:39 AM
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Thank you - I will give it a try.
 
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Old 02-04-2008, 12:38 PM
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did you clean point contacts before installing,sometime have residue on the that won't alow contact
 
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Old 02-04-2008, 01:00 PM
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I did not clean, but tested with old points and new- both had no spark. The harness on this truck was pretty much intact, A pink resistor wire was cut under the dash, but I reconnected- but it says right on it-do not cut- could this be part of the problem?
 
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Old 02-04-2008, 01:09 PM
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if you have 12v to positive side of coil and didtributer to negitive and no shorts in dist wire it should spark
disconect wire from points and touch to ground and see if it sparks,could be shorted condensor or broken dist lead


BTW these normally start on 12v and run on 6v
 
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Old 11-15-2008, 06:48 PM
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I am also having an issue with my 76 Ford. I am not getting spark. I have just replaced the old harness with a new harness due to age and wear. Now I can't get spark - the truck ran when it was parked. I have replaced battery, Ignition Module, Starter Relay and Stator in Distributor - just to make sure all would be good. I have another 76 Ford in the yard so I swapped Coils and it is good for sure.

All of my spots to be hot in on position are all hot and running to ignition module Red/Blue and Blue Or white and Red from module. Red on Module comes to Blue on harness, this then wires to the + on Coil, to Red/Green on Voltage Regulator, To Starter Motor Relay on I - Side and back to Ignition inside truck. The Red/Blue Goes to "S" on Relay and Starter wire from ignition inside truck.

What is going to feed my Orange or Purple Wire in the run position? All is right in the on position as far as power to each wire. That is where I am thinking I have an issue is getting the right signal in the run position. I am doing this on my own and finding it impossible to turn the key and be under the hood testing the distributor at the same time - Any Ideas?

Your information to a previous poster has helped me to figure all this out to the point I am at now and hopefully you have the wisdom I need to figure the start sequence to the distributor. Thank you so much for your time. Melodie
 
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Old 11-16-2008, 10:29 AM
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I am assuming that you are working on a bronco? Most of the info in the previous post was for my 68- and will be alot different for your 76 since ford went to electronic ignition by then. Check out my posts under the 73-79 f150 forum on this site- I had similar problems with my 79 150 and the electrical systems will be similar between your 76 and 79.
 
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