hey guys, i'm in a bit of a jam as of right now, my 1970 F250 highboy is acting up something fierce, and neither I or my Dad have no clue as to why it would be doing this. For starters, my truck's engine specs as they are related to the situation are as follows:
360 cubic inch engine
standard carburetor, has been cleaned 2 summers ago
ACCEL Super stock 12 volt ignition coil, O'Reilley's part #:8140
ACCEL points eliminator kit
Standard Fuel pump
New Rebuilt Alternator from O'Reilley's

Now for the problem at hand, last Friday, i was hauling some things in my truck, my coolant was around 1/4 full, but as far as i had known so far, it had been at 1/2, now, i had finished hauling my cargo across my town, I parked it and helped my dad with a couple things, and i returned to my truck to find that it would crank over just fine but it wouldn't start. I started smelling gas and i quit, suspecting that i had accidentally flooded it and waited about 30 minutes before trying again,and 2 hours later I wasn't reaching a solution. I called over my dad and we tried everything we could think of, drip a couple drops of gas in the carb, etc. we eventually looked at the ignition coil and found that it had been leaking oil from its vacuum sealed casing around the coil (helps with the heat management) this in turn was messing with my connection between the distributor and the coil. I ended up buying a new coil and installing it, the engine started right up after that, later in the day, i was using and going down the highway in my town, the engine just bogged down and quit on me, it acted as if it had just flooded itself again, I was able to stop, off of the highway of course, and get a look under the hood, i did a spark test with the ignition coil wire running to the distributor and it sparked somewhat erratically, other than that, from what i could tell, everything was sitting ship-shape, nothing out of the ordinary. my theory behind this weird occurrence that came out of nowhere, is that the wire leading to my ignition coil is going bad and needs to be replaced, either that or the distributor cap is going bad due to wear and tear (ordering a new one soon) and is not allowing the sparking to happen normally.

Does anyone have any advice or ideas on how to deal with this?
Thanks in Advance!!

 

First welcome to FTE.

So lets say it is a spark thing based on what you posted.
When checking for spark did you pull the coil wire from the dist. cap end and hold it about 1/8" from ground like the intake or block?
If not and going back into the cap could give bad feed back "sparked somewhat erratically" but can be used as a test.
Test to ground if you did not and tell us what you get.

On that points eliminator kit and the old & new coils, do they need a full 12 volts or run off a resister wire at reduced volts?
I ask because that coil leaking would point to that the coil over heated and that would be from it getting a full 12v when it should not.
I also know some of the points eliminator kits need a full 12v to work right. I also heard they will run good for a bit then mess up like yours.

If you have the points could go back to them for testing to see if anything else, cap/rotor/wires/plugs, may be bad.
Dave ----

 

Yes, I used the wire running from the ignition coil to the distributor and held i about an 1/8th of an inch away, i used the term "sparking erratically" because it would spark, the engine would continue to turn over and it would randomly spark again anytime after that. I also checked my distributor cap and the points are nearly black and seemed to be corroded as well, maybe this is limiting the spark....
here also seems to be a chip in the bottom lip of it as well, and as stated before, i'm looking to get a new one in it soon.
As far as what you were saying about the resistance wire, how would i check to see if that's how my ignition coil is wired?
UPDATE: New distributor Cap is in, seems to turn over and try to spark more precisely, still doesn't take off and keep running.....

 

There's a problem right there....carbon arc-over, basically rendering the cap useless...as in a high degree of resistance for spark


Sooner the better...

Originally the coil (+) terminal was hard wired with a 1.3 Ohm ballast resistor wire which limited the voltage/current to the coil down to ~ 8 - 9 VDC when in RUN. Over time and wear, the resistance wire would go south, allowing either 12 VDC to the coil (+) terminal or nothing at all. 12 VDC to the coil (+) terminal would eventually fry the coil as OEM coils weren't made to run on BATT voltage. The only exception would be is in START where BATT voltage is applied momentarily to the coil (from the "I" solenoid terminal) as an aid in starting.
Now that some basics are done, and you are now expert in the START/BYPASS ignition circuit.
To test the ballast resistor wire: with the KEY ON, Engine OFF, measure the voltage from the coil (+) terminal to a good, clean ground. You want to see ~ 6 - 8 VDC....if the ballast resistor wire is functioning normally.....but if you need BATT voltage for your setup to run optimally, you need BATT voltage delivered to the coil (+) at all times.

Dave, AKA FuzzFace 2 has got you covered on this.......

 

Alright, thanks for the advice so far guys, ill try to continue to test the components sometime tomorrow, but theres still one lingering thing in all of this for me... why now? my truck has worked perfectly fine the past 3 years, ignition coil, points eliminator kit and all, but it suddenly decides to go bad now of all times?

 

That's the way it always happens, no notice, text, or email, it just goes bad.

 

Did the rotor get replaced too? One thing to consider is the old points style distributor ignition system hardware has to be 100% if a hotter full-voltage coil is installed - cap, wires, everything. Secondary or high tension voltages are higher and any defect in wiring and grounding will be exposed. When electonic ignition replaced the points they went to distributor caps with larger diameter & wider spacing to prevent crossfire and external arcing. Look for arcing at night or dark garage. Have seen rotors burned completely through internally. Just something to be aware of.

 

Update on the status of my truck, i have tested the voltage of my alternator, ignition coil and battery, they're all getting 12 volts and my coil is equipped to handle that, my next resort is to pull out my entre distributor, points kit and all and manually examine and clean it, if that still doesn't work, i'm planning to pull and test each spark plug and each wire and just replace them all.

 

I'd suggest that you do those two in reversed order: remove your spark plugs & wires first. Reading the color of your spark plugs can provide a valuable diagnostic for you. Besides, you'll want the spark plugs out before you remove the distributor anyhow.

If you DO pull your distributor, rotate the crankshaft manually until the #1 Cylinder is at top dead center. Then remove the distributor cap and take a picture of the rotor's orientation. This will give you the information you will need to successfully re-install the distributor.

 

IMHO what ever fried your coil also hurt the points eliminator kit. Or vise-versa. In the past few years there has been a few bad Accel brand ones. If it were me I'd buy GENUINE FORD (MOTORCRAFT) points and condenser and install them. NOT AFTERMARKET! The aftermarket condensers are JUNK. Along with an aftermarket new cap and rotor. I bet the truck will fire right up as long as the points are adjusted and greased correctly. If this does prove the Accel kit is bad I'd order a Pertronix brand one. The truck is running with the points so you would have time to get in the Pertronix.

Ford (Motorcraft) part numbers still available.
B8Q12171A (DP12)...points.
C9AZ12300A (DC13A)....condenser.

Area on the new points to put a dab of dielectric silicone grease (same as disc brake caliper slide grease).