I had to replace the distributer in my '69 that some previous owner put a 460 in. I am having trouble with the ignition system. I can't seem to get it timed properly, and I have a very weak spark, (yellow and hard to see). I bought a new coil, the parts guy thought that fords had internal resisters in the coil. When I put the new one on I had no spark at all and it got very hot to the touch I have 13 volts at the plus side of the coil, with the key on, but no spark on the engine. What might I have done wrong during the repair.

 

Just a thought, some used a resistor "wire" from the ign switch to the
coil. That you will have to check. So if you do have resistor wire plus
internal resistor coil then you will have very little or no voltage. Regular
store bought shop manuals dont mention this, but its in the genuine
Ford manual.

 

I had heard of the resister wire before but wasn't sure where and on what engine. If I had that setup and it was working properly wouldn't I have less than 12 or 13 volts at the positive side of the coil. Otherwise you make perfect sense 2 resistors might make for not enough voltage to make a spark.

How would I check if I am supposed to have a resistor wire. The only thing I know for sure is that is old enough to still have points. It is even possible that it is a 429. Almost nothing is stock on this truck so I am really starting from scratch. I have no idea what the engine came out of originally and the timing settings vary by year and model in my manuals, even the points gap is different from model to model.

I am getting in over my head a little bit I think on this one. I am a competent parts changer, but not a real mechanic.

 

This thread will explain things on spark issue https://www.ford-trucks.com/forums/8...ml#post8005595

On the timing issue .. The outer shell (with the timing marks) on the harmonic balancer could have spun then your marks are off .. Look it over good .. The rubber that separates the 2 pieces can start to come out over time if this is the issue it should be replaced .. When looking from the drivers side fender if the has a wobble this is another indication of the rubber separation .. If you just need to get it going before you get around to changing the harmonic balancer purchase a piston stop to find top dead center and set your timing from there .. if you need clarification on how to use a piston stop to find top dead center just say so



Piston stop

 

According to that link I need a coil without an internal resister. I didn't get a chance to mess with it this weekend but thanks a lot for the reply. I will study that link further and try to get back on it next weekend. Thanks again for the reply.

 

If the distributor cam was holding the points OPEN while you were measuring the voltage at the battery side of the coil, you WOULD read battery voltage, even with the resistor wire in the circuit. Because with the points open, no current flow, so no voltage drop across the resistor wire.

My 1970 460s had a pink resistor (nichrome) wire from ignition switch to coil. With years of age, the pink didn't always look pink everywhere.

With points, your capacitor ("Condenser" in old auto talk) needs to be in good shape, and can't beat a dwell meter for measuring and setting points, once you can get it running. Weak spark can be a bad cap, or points too far open or too far closed. Also pitted points. Used to be common for some of the contact material to tack on to the other contact, so one contact had a pit, the other contact had a tiny mountain on it.

GM engines of that era were really nice, there you just lifted up the little sliding metal door on the side of the distributor, inserted an allen wrench, and adjusted the dwell by turning the allen wrench. I never used a feeler gauge on any GM that I had with points. For some reason, the Chevy 250 six didn't have a window, but I didn't own one of those.

EDIT - Another thought - Also check the wire that goes under the breaker plate, the one that goes out through the side of the distributor. They can fray, get intermittent, rub through their insulation on the breaker plate when the plate moves for advance. Rockauto used to have them, but they sold them in a pack of x, not single.

 

Long overdue update. My new distributer had a bad condenser, I replaced it and it started without even touching the gas pedal, and ran smooth as silk.

Thanks for the replies.