hot coil
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From: Manteca, CA
hot coil
locking up truck last night and smelled something...turned out that the coil was boiling. disconnected battery and removed coil. spewed oil all over engine and driveway. truck ran fine all day. my question is did the coil just go bad...or do I have other things to check. I will get new coil Monday, wondering if I need to check anything else. thanks
Joe
Joe
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From: Upstate NY
Never had one boil out like that but sounds kind of fun. Makes a great story! Coils are just special purpose transformers. They consist of many windings of copper and are immersed in oil to help cool them thru heat transfer. Sounds like yours just shorted out and heated things up a bit. Was it an old original type or Chineese replacement? It should be a localized problem and changing out the coil should take care of it. Good thing you turned it off when you did, potentially there could have been flames and your troubles could have been worse! More often then not, when a coil fails it dosen't look any different on the outside than when it was working. At least you know where the trouble is now!
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From: Manteca, CA
ya, I was taking off coil wire and it was hot and stunk! it was about 5 hours after I drove as well...crazy. I will replace tomorrow and hopefully have 1 more thing solved. I would assume it was original...all black, no writing. I am glad it didn't turn into a bigger problem!!!! thank you for the help. I see some offered with ballast resistor...I don't think that I have a ballast resistor now...at least not one that looks like the one in pictures.
Never had one boil out like that but sounds kind of fun. Makes a great story! Coils are just special purpose transformers. They consist of many windings of copper and are immersed in oil to help cool them thru heat transfer. Sounds like yours just shorted out and heated things up a bit. Was it an old original type or Chineese replacement? It should be a localized problem and changing out the coil should take care of it. Good thing you turned it off when you did, potentially there could have been flames and your troubles could have been worse! More often then not, when a coil fails it dosen't look any different on the outside than when it was working. At least you know where the trouble is now!
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From: Upstate NY
A '60 uses a resistance wire instead of a ballast resistor. Much has been discussed about this topic. This wire runs between the run posistion of the ignition switch and the coil to provide about 6 volts to the points while the truck is running. The points recieve the full 12 volts during the start mode. This all happens to keep the point from premature failure. How's that, clear as mud?
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From: Manteca, CA
Makes perfect sense, got replacement coil tonight and truck started right up so I knew points weren't fried. Wires all looked good as well. Guess the coil just went bad. I noticed that there was a small crack by negative terminal when I looked at closer today and it was an AC delco coil to boot! Kind of a freak thing I guess. Thanks for the help
Joe
Joe
A '60 uses a resistance wire instead of a ballast resistor. Much has been discussed about this topic. This wire runs between the run posistion of the ignition switch and the coil to provide about 6 volts to the points while the truck is running. The points recieve the full 12 volts during the start mode. This all happens to keep the point from premature failure. How's that, clear as mud?
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From: N E Ohio
You might want to make sure there is no power to the points or coil when the ignition switch is off. The coil can only heat up when power is applied. If the engine stops with the points in the closed position, a problem in the ignition switch, starter relay, or wiring can allow constant power to the coil, overheating it.
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From: Manteca, CA
sounds like a great idea to me. I have disconnected positive batt cable until I am 100% problem is solved. at the risk of asking a dumb question...what is easiest way to test no power to coil/points with ign. off? test light to positive side of coil? I admit I am no whizz in electrical... Seeing that I noticed the coil was boiling about 5 hours after last driving, I would say this is a must do
You might want to make sure there is no power to the points or coil when the ignition switch is off. The coil can only heat up when power is applied. If the engine stops with the points in the closed position, a problem in the ignition switch, starter relay, or wiring can allow constant power to the coil, overheating it.
Last edited by Maltman; Sep 10, 2013 at 11:58 AM. Reason: ADDITION
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From: Upstate NY
Simple way to check for power to the points is to take the dist. cap off and see if there is a spark when you manual open up the points with your fingers! Just lift the one side back to do this. If they are apart, touch them with a screw driver and watch for sparks. Best not to be in the bright sun. Now of course, the best option is to use a multi meter and check for power at the terminal where it attches to the dist. or at the coil, but anybody can do it that way!
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Yes. You can use a test lamp, or a multimeter set on volts to check it. With ignition off, and points open, there should be zero volts at either end of the coil to points wire. Another check is with the test lamp or meter, with ignition odd there should be no voltage at the + (ignition switch) terminal of the coil.
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From: Manteca, CA
right on, I checked last night. I have no multi meter so I used my test light and had no power to coil or points wire with key off. I know this isn't accurate, but I always test the light on battery before anything else-had a bright light. when I checked the hot side of coil with key in "on" position but not running...seemed to be half as bright as compared to battery light. 12v compared to 6v...poor mans multi meter. thanks for all the help
Joe
Joe
Yes. You can use a test lamp, or a multimeter set on volts to check it. With ignition off, and points open, there should be zero volts at either end of the coil to points wire. Another check is with the test lamp or meter, with ignition odd there should be no voltage at the + (ignition switch) terminal of the coil.
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