Troubleshooting Ignition System - 74'/350
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Troubleshooting Ignition System - 74'/350
I have the original style points and distributor on my 350/74'. With the engine not running and the ignition key turned to run, what voltage should I see at the plus side of the coil? Thanks.
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
The Ignition sticky at the top of this section will explain why.
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Since it is not easy to tell if the points are open or closed, I assume I can just ground the coil minus terminal and do the voltage check to verify that I get the 6 volts (or so) reading. Can someone confirm this approach?
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I have been burning up points - only getting about 1000 miles on a quality set of points so I wanted to verify that I had the right voltage going to the points in the run position. Otherwise ignition system works fine.
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From: Long Island
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From: Long Island
Thanks for the reply. With the car running or not? If not, wouldn't there be a difference if the points were in an open or close position as mentioned earlier. Please clarify - thanks !
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Ultimately I pulled the starter and replaced the starter solenoid since I was seeing full battery voltage with the key in run and the engine not running. The removed solenoid seemed to test out ok but a bad solenoid was the only explanation I could come up with for seeing full battery voltage at the plus side of the coil (when the starter was not engaged). With the new solenoid I now measure about 6 volts at the plus side of the coil with the key in run and the engine off and the points grounded so I think the issue is resolved but will not really know until I put some time and miles on the car.
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Okay to confirm - key in run position (car NOT running) measure voltage at + side of the coil. Correct voltage should be between 6-9 volts? With car car running, voltage at the + side of the coil should be what? Thanks
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From: Long Island
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From: Long Island
what value is the resistor and how did you bypass the resistor wire (guage etc)
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It is a standard automotive ballast resistor, havent heard of them coming in different ohm ratings, but you still havent stated what voltage you are getting with the engine off and the key in the run position at the positive terminal of the coil.
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