I was just tring to start my flathead it had been working fine. opened hood to fine what looked like gas or oil. i found that the neg terminal from 6 volt coil had poped out and sprayed oil all over engine compartment. now there is a hole where terminal fits into coil . only thing i can think of is i have 12 volt battery hooked up but 6 volt generator is disconnected. as i said it was running and starting up just fine. anyone hear of this happening before?
The same thing happened to our forklift at work. Some wires shorted out (got slamed in the hood) and caused the terminal off the coil to explode. It also burnt up the points (or the points were already burnt up.) I'd check for a short in your wires. PS I was the only guy at work who had ever worked on points.
It had been running fine driving fine. time for a new coil at the least hope everything else is fine.
the resistance of the coil internally is the factor for current drain..running a 6 volt coil on 12 volts will actually double the current across the coil and points..usually the coil will heat up and shut off prior to fire/heat pressure related damage..the points are taking a great hit also ....the coil and points will permit starting on the 12 volts but should immediately drop back to 6.8 (thereabouts) for constant run..do get yourself the proper dropping resistor to match your replacement coil and wire appropriately..new points and condenser would be a wise move at the same time.
Some people use gas or solvent to clean parts, if a small amount were to seep into the coil from a small crack.....years ago I had one go off, it filled the engine compartment with copper wire from the coil. It was about as loud as an m-80.
I have not checked the points they were brand new. Seems like coil was over loaded. I hope the points are ok
TODD...whatever you hooked up wrong, it fryed the coil. want some good advice, get a mechanic to look her over, before you burn the car up...POP.
I was told you could use 12 batt to start as long as you disconnected generator. This is why I'm so suprised that coil would blow.
That is correct but as adams said after starting you want a resistor in line. On the older 12V cars (which used a 6V coil) when the ignition is in the start position it by-p***es the resistor, then when you release the key to the run position the resistor gets back in line.
Ballast resistors allow full voltage to go through until they get hot (this is why they have porcelain housings) thereby delivering a spark boost at initial startup only. Once the engine starts, the resistor gets hot and lowers the voltage to the coil. Without the resistor, the coil overheats. Oil filled coils can boil and blow the oil out. Epoxy filled coils can melt. Disconnecting the generator only served to protect the generator and regulator from the higher voltage. No ballast resistor was there to protect the coil.
so do you rehook up the gen.after it starts?i know i have put a 12v batt.in a 6v car to get it started and man does it turn over.i never left it in though.why dont you just put a 6v battery init?i agree that the coil prob.blew because it isnt sup.to get 12v all the time just durring cranking the the ballast resister takes it down to i thought 9v but its been a while since i checked one.
Its running great now new coil 6 volt battery generator wired in I also found that coil had been wired in wrong before they had distripitor wire going to neg post not positive post. I had also been told that you can use a 9 volt battery in a 6 volt system is this true? without any other modes.
I need to add this to my list of "things that make you go "Hmmmm?"" As I understand it, the ballast resistor is only in the circuit when the ignition switch is in the "on" position, and is so to drop the voltage to the coil while the car is running. When the ignition switch is turned to the "start" position, the ballast is byp***ed, usually by way of contacts in the starter, so that a higher voltage is delivered to the coil during engine cranking. So while your explanation may be true in some cases (??), I have many automobile schematics to corroborate my understanding of the wiring of the ballast, and how it functions in the circuit.
Self-variable resistors Some ballast resistors have the property of increasing in resistance as current through them increases, and decreasing in resistance as current decreases. Physically, some such devices are often built quite like incandescent lamps. Like the tungsten filament of an ordinary incandescent lamp, if current increases, the ballast resistor gets hotter, its resistance goes up, and its voltage drop increases. If current decreases, the ballast resistor gets colder, its resistance drops, and the voltage drop decreases. Therefore the ballast resistor reduces variations in current, despite variations in applied voltage or changes in the rest of an electric circuit. These devices are sometimes termed barretters.
True, learned all about that in electronics school back in 1972, and you are correct on all counts. However, in order for the current to increase through the ballast, one of the two things you mentioned would have to happen. 1.) The voltage would have to be increased, or 2.) The resistance of the coil would have to decrease. My experience points to these two possible variables as being fairly constant in a well-maintained vehicle, hence the ballast resistance doesn't change much at all. My initial response was related to the suggestion that it is strictly the variable resistance of the ballast that reduces the current flow through the coil/points once the engine starts. Schematics of the ballast byp*** circuit in virtually all vehicles that ever used one suggest otherwise. If it was strictly the ballast doing all this, the auto makers would never have gone to the trouble & expense of building starters with byp*** contacts, and the ***ociated wiring that goes along with the circuit.
Your'e negative terminal on the coil goes to the points.....if it's negative earth. The way you explained it works if it's positive earth.
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