bad coil ground?? missing badly after moving coil

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Is this electronic ignition or points?

Burned points from leaving the key on, engine not running, points closed?
Have you checked point gap?
Is your condenser well grounded?
Have you done voltage drop testing to see if you have any undesired high resistance? What you describe sounds like a primary side issue...

If you have electronic ignition, pull your coil wire and hold it close to a good ground. Grab a Weller-style soldering gun and bring the soldering gun housing close to the ignition module and trigger the gun. Coil should fire at 60 Hz from the induced field - meaning module is OK. Check for damaged wires on dist. pickup assembly (rotation of breaker plate by vacuum advance can cause intermittent drop-out.)
A few ideas to start with. From your description, I would put money on the burned points if this is a mechanical distributor.
 
the new coil seemed to fix the fire to plug issue if i hold the plug close to the block and crank the engine over i now have spark to all of them
 
64SignetConv said:
Is this electronic ignition or points?

Burned points from leaving the key on, engine not running, points closed?
Have you checked point gap?
Is your condenser well grounded?
Have you done voltage drop testing to see if you have any undesired high resistance? What you describe sounds like a primary side issue...

If you have electronic ignition, pull your coil wire and hold it close to a good ground. Grab a Weller-style soldering gun and bring the soldering gun housing close to the ignition module and trigger the gun. Coil should fire at 60 Hz from the induced field - meaning module is OK. Check for damaged wires on dist. pickup assembly (rotation of breaker plate by vacuum advance can cause intermittent drop-out.)
A few ideas to start with. From your description, I would put money on the burned points if this is a mechanical distributor.
Click to expand...

it is electronic no points everything has been recently replaced
 
Then next question is - have you checked your engine-to-body ground? Post #2 suggested a fix that worked not because he grounded the coil case, but because he fixed a bad body ground (I suspect). Check the voltage drop on the ground side of the ignition module - right back to the neg. post of the battery.

Remember that when the coil fires, the engine block is the positive side of the circuit. Electrode tip of the plug is negative (that is part of the reason that the tip erodes). A solid ground between battery, engine, and body is vital.

I assume you have checked the other items people have suggested (manifold gasket leaks etc.?)
 
Oh yeah - if you replaced the pick-up in the distributor, did you set the air gap? Brass feeler blades - 0.006" to 0.008"

Electronic ignition is a pretty basic circuit - not a lot of checks to do.
 
thanks for the help i pulled all the plugs after it wouldnt even crank and they were all soaked in gas and very black im hoping new plugs will do it maybe i fouled them before i got the electrical prob fixed
 
put in new ones still wont stay running fires immediatly dies. put in new ballest resister no better shoul the pos side of the coil be grounded when the key is off? the broen wire and the redblue wire on the ballest resister also grounded. tried the old carb with adapter same prob not change. before it ran but missed now jus farts and quits
 
At key-on, the transistor in the control module grounds the coil. At key off, the transistor shuts off and the field in the coil collapses, causing a spark. Therefore you should get a spark from the coil wire with every key on-off cycle.
 
If this helps - here is a basic wiring diagram of a module-type ignition system. Match the wire colours in your harness to what you see here.

J6 & J7 (usually brown and grey or black and grey) are the wires between the pick-up and the module. Measure with an ohmmeter at the module connector - normal is 600 t0 1500 ohms.

J5 (Black with yellow tracer - might be different on yours) connects the negative side of the coil to the module. The module supplies a ground on this wire to energize the coil, disconnects the ground to fire the coil. Disconnect the wire fro the coil, attach a test light between the wire and the positive terminal of the battery and crank the engine. Test light should flash while cranking.

J9A (Pink most often, may be red with or without tracer) supplies the positive side of the coil from the ballast resistor. In crank mode, the J9 (Pink or Red - with or without tracer) wire from the starter relay by-passes the resistor to supply full cranking voltage to the coil for start. With the key on, all wires connected, there should be about 5-7 volts at the positive side of the coil. With the starter relay energized, but the engine NOT cranking (disconnect the brown wire going to the starter solenoid) there should be full battery voltage at the coil positive.

J10A and J10C (almost always red) supply full charging system voltage to the module and ballast resistor respectively. Key on, engine off there should be battery voltage at both of these locations.

if all this checks out, and you have verified the coil wire (ohmmeter - about 7000 ohms/foot), the rotor, the cap, the coil (you replaced it, right?) and the air-gap on the pick-up, then your problem is non-ignition related. In my opinion.

ign3-1.gif
 
im starting to think its the intake. ive got fire and put new plugs ballest resister and no change.
 
Diagnose instead of throwing parts at it. It's cheaper.
Vacuum readings?
Propane torch (unlit and barely seeping) along intake-to-head parting line - look for RPM change.
Crossover allowing exhaust gasses into intake?
Carb circuits plugged? Carb over-fuelling?
Hate to ask - but I have seen this before - you are not numbering the cylinders like a Ford (1-4 on left bank, 5-8 on right bank) when you check firing order are you?
 
64SignetConv said:
Diagnose instead of throwing parts at it. It's cheaper.
Vacuum readings?
Propane torch (unlit and barely seeping) along intake-to-head parting line - look for RPM change.
Crossover allowing exhaust gasses into intake?
Carb circuits plugged? Carb over-fuelling?
Hate to ask - but I have seen this before - you are not numbering the cylinders like a Ford (1-4 on left bank, 5-8 on right bank) when you check firing order are you?
Click to expand...


cant try the propane around the intake or vacuum reading for it want stay running long enoungh. tired another carb on an adapter no difference not numbering cylinders like a ford. the only thing i changed was the intake and carb prior to this it was fine the day before. def dont want to buy any more uneeded parts
 
64SignetConv said:
Then next question is - have you checked your engine-to-body ground? Post #2 suggested a fix that worked not because he grounded the coil case, but because he fixed a bad body ground (I suspect). Check the voltage drop on the ground side of the ignition module - right back to the neg. post of the battery.

Remember that when the coil fires, the engine block is the positive side of the circuit. Electrode tip of the plug is negative (that is part of the reason that the tip erodes). A solid ground between battery, engine, and body is vital.

I assume you have checked the other items people have suggested (manifold gasket leaks etc.?)
Click to expand...
Actually, the body ground was the second thing cleaned. It was fine as I figured, cause I use high copper never sieze on most connections. stuff works good. And I tried to fire it with each componet cleaned/replaced. Witch made me believe the coil needed grounded. But I`m no pro mechanic. I learn a lot the hard way8) To the OP, Did you buy an Intake that was possibly milled for correction on its previous engine? Is their any gap, front view, where the ports attach to heads? Its gonna be hard to tell until you get it running long enough to spray around the sealing areas. Make sure your carb is doing what it is supposed to do also. Float level, not stuck open etc. choke adj. hope its not a DP?
 
Tell us more about the intake - new or used? If used, do you know what it came off of?
Is there an EGR block-off plate?
Any chance of a pic or two...?

I agree with Mopar Head - check the basics on the carb and look for indicators...
 
64SignetConv said:
Tell us more about the intake - new or used? If used, do you know what it came off of?
Is there an EGR block-off plate?
Any chance of a pic or two...?

I agree with Mopar Head - check the basics on the carb and look for indicators...
Click to expand...


beleive it was a late model 273 no egr was used on another 318
 
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