hey guys, been struggling with this car. its a 1955 dodge coronet 270 poly head 6v positive ground. i get a (1) spark off the coil wire when i stop cranking it. ive replaced the coil, cap, wires, plugs, capacitor. the points seem fine, they open and close and are clean. bad ignition switch? thoughts?
Could be that the wire from the points to the coil is shorted to ground somewhere? Do you have a volt meter, and know how to use it to test continuity?
sounds like its time to get one!! probally cheaper than replacing stuff endlessly! gonna grab 1 tomorrow am
First do a close inspection, to see if there is any place that the wire might be shorted to ground. Also, have you verified that the distributor rotor is actually turning?
the rotor turns, points open and close. i recently replaced the power lead to the coil. which wire are you referring to grounding out? the lead to the coil, the wires in the distributor or the ground from the coil
The primary (small) wire from the points to the coil. Maybe you have it wired wrong, if there is a ground wire going to the coil. Pictures could help.
I can't see exactly where the yellow wire off the + side of the coil goes to...does it connect to the stud and nut on the side of the distributor? As for checking for shorts, I would first look very carefully at the little wire inside the distributor, that connects one of the points to that stud on the side of the distributor. If it is making contact with the distributor housing or breaker plate, it will short circuit the points, and the engine won't run. If you have an Ohm meter (which is part of a normal modern handheld digital volt meter) you can disconnect the wire from the coil, then measure the resistance of that stud, to ground. It should be an open circuit if both sets of points are open, and closed when either or both points are closed.
yes, the yellow wire attatches to the the nut on the side of the distributor. I'm going to get a volt meter in the am, i'll poke around and check those wires we've had this car for a few years... it runs it doesnt run. the joys... remind me.. is this fun?
Check real close to see that you don't have the something grounded out in the distributor. Wire end on the wrong side of the insulating block where it connects to the screw coming from the coil lead? Part of the insulator for that screw missing or in the wrong place letting the lead ground out. Wire end turned a bit so the end is grounded out. The points are the switch for the coil. When they are closed a magnetic field builds up in the primary winding and when they open that field collapses sending a high voltage charge from the secondary winding to the spark plug. Having the lead grounded would build up that magnetic field when you cranked it and it would collapse and send one high voltage shot through the coil wire when you quit cranking just as you are seeing.
Check right in this area to make sure that you don't have something shorted out. Or on the wrong side of the insulator so it is grounded/shorted to the housing.
That yellow "primary" wire from the coil to the distributor looks like a homemade replacement. Like Squirrel says, inspect it for a short and also for an internal break or bad crimp on the end lugs. The copper can get unintentionally stressed but the plastic insulation hides the internal problem. Easy inspection, easy fix. One time, back in the 60s, my brother and I were making a midnight run to Juarez, Mexico and his '55 Chevy quit cold, no spark, way out the dark boonies. We're on the side of the state road with our thumbs in our butts, no flashlight, and could see for miles but couldn't even see a porch light or approaching headlights anywhere. It seemed like hours, but it was probably minutes, and a car slowed to look us over and stopped. He had a flashlight and we fixed the little primary wire in one or two New York minutes and were on our way again.
thanks for all the tips guys.... cant wait to stand hunched over tomorrow snarling like a junk yard dog trying to get this thing running again, so i can move on to the brakes!!
loosen up that yellow wire on the coil and clock it away from that rubber boot ,might be shorting to there.
If you suspect the condition of the points it should be an easy matter to disable each set of points, one set at a time, and see if it will spark correctly when cranked over. Try putting a thin piece of cardboard between the contacts to temporarily insulate one set of points at a time. Either set of points should be able to fire all 8 cylinders by itself since the distributor has an 8 lobe cam. If you haven't already, you might pull the spark plugs to make it easier to crank over. Saves a little wear and tear on the starter and battery.
i found a small fray in the wire under the thicker black wire, hit it with some electrical tape temporarily and i have spark off the coil wire finally.... trickle charging the battery til tomorrow..
Try powering the negative terminal on the coil with a jumper wire directly from the negative terminal of the battery. Make up a piece of insulated wire withan alligator clips on each end as if it starts you will need to disconnect one end to shut off the engine. If it runs with the jumper wire, then the fault is likely in the ignition switch, or between it and the coil.
ignition switch should have both a start circuit and a run circuit sounds like the higher voyage start circuit may be bad so its only tries to start as you let off the starter switch and the tow circuits over lap as circuit switch one to the other
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