wiring problems. Coil got hot
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wiring problems. Coil got hot
So I'm trying to get my 69 vette to fire up after being apart. I have all the wires right on the starter solenoid, and they are correct on the alternator. The ignition is correct. So I must have the coil wrong. the negative side has the wire from the distributor and the wire from the capacitor that is attached to the coil. I have the wire from the solenoid going into the positive post on the coil and that 20 gauge wire (braided cloth insulation) goes out and into the fuse box. from there it turns into a 12 gauge pink wire that goes into the ignition. All this seems to be correct, but this wire gets hot when the key is on. It gets hot kinda slow, but it and the coil both get hot eventually. I can tell they are heating up in about 15 seconds. When I had the key on, I was reading 6 volts from the positive post to the negative post on the coil. I though it should be 0. and i was getting 12 volts from the positive post to ground. I think that is normal.
I tried a different coil, and that braided wire still heated up.
I would appreciate advice.
I tried a different coil, and that braided wire still heated up.
I would appreciate advice.
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Joined: Jun 2004
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
So I'm trying to get my 69 vette to fire up after being apart. I have all the wires right on the starter solenoid, and they are correct on the alternator. The ignition is correct. So I must have the coil wrong. the negative side has the wire from the distributor and the wire from the capacitor that is attached to the coil. The capacitor should attach to the + side. It's a noise filter, not a points protector. I have the wire from the solenoid going into the positive post on the coil Sounds correct, as long as it's the R terminal, and not the big battery terminal. and that 20 gauge wire (braided cloth insulation) goes out and into the fuse box. from there it turns into a 12 gauge pink wire that goes into the ignition. All this seems to be correct, but this wire gets hot when the key is on. Do things still get hot when the points are open? It gets hot kinda slow, but it and the coil both get hot eventually. That will happen if the points are closed. I can tell they are heating up in about 15 seconds. When I had the key on, I was reading 6 volts from the positive post to the negative post on the coil. I though it should be 0. The coil primary windings have about 1.5 to 2 ohms of resistance. If the points are closed with the engine not running, the current flowing in the circuit will cause a voltage drop of about 5 to 8 volts across the coil. and i was getting 12 volts from the positive post to ground. I think that is normal. That should happen only if the points are open (which would not allow you to get the previous reading of 6 volts across the coil), or you have a "short" from the battery to the + terminal. I tried a different coil, and that braided wire still heated up.
I would appreciate advice.
I would appreciate advice.
It's midnight. I'll check in tomorrow.
Melting Slicks
Joined: Mar 2005
Posts: 2,838
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From: Austin TX
That braided wire will get hot. It's a resistor wire that's meant to reduce current so the points won't fry. This lost current is converted to heat, hence the cotton braided insulation. It's also the reason there's an accessory position for the ignition key. If the key was in the "on" position with the engine off, that wire can get very hot.
FWIW
FWIW
Race Director
Joined: May 2006
Posts: 16,528
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From: Dayton, Ohio
That braided wire will get hot. It's a resistor wire that's meant to reduce current so the points won't fry. This lost current is converted to heat, hence the cotton braided insulation. It's also the reason there's an accessory position for the ignition key. If the key was in the "on" position with the engine off, that wire can get very hot.
FWIW
FWIW
edit- never mind 69427 answered the question,i didnt read well enough.
Last edited by ...Roger...; Sep 11, 2009 at 06:02 PM.
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I tried disconnecting the condenser, that didn't help.
I don't understand. when the key is on, I am getting 6 volts to ground from both the positive terminal and the center conector that goes to the center of the distributor cap. when I turn the engine over I am showing 8 volts coming out of the coil. I thought it should at least be a couple hundred volts that goes to the distributor, not 8. when I unhooked the negative battery terminal it was noticably warm. I have a problem somewhere, but all of the wiring seems correct. I had the alternator tested and it's fine.
I don't understand. when the key is on, I am getting 6 volts to ground from both the positive terminal and the center conector that goes to the center of the distributor cap. when I turn the engine over I am showing 8 volts coming out of the coil. I thought it should at least be a couple hundred volts that goes to the distributor, not 8. when I unhooked the negative battery terminal it was noticably warm. I have a problem somewhere, but all of the wiring seems correct. I had the alternator tested and it's fine.
