wont stay running'????
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Joined: May 2001
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From: Rhode Island
wont stay running'????
ok here goes
i transplanted a 80 302 into a 84 pickup,, everthing went fine , until i tried to start it ,,,,,she will crank , and crank ,, but wouldnt start,, until one day i noticed , that if you hold the ignition switch just after start,,, she will stay runnin,,,the truck ran fine before i changed the motor,, so i dont beleive that it is the switch ,, is their anyway to bypass the switch so as to make the truck run without having to hold the switch???
I installed the wiring harness from the 302 ,,, msd ignition ,,, new coil,,,, etc etc etc,,, any ideas????
i transplanted a 80 302 into a 84 pickup,, everthing went fine , until i tried to start it ,,,,,she will crank , and crank ,, but wouldnt start,, until one day i noticed , that if you hold the ignition switch just after start,,, she will stay runnin,,,the truck ran fine before i changed the motor,, so i dont beleive that it is the switch ,, is their anyway to bypass the switch so as to make the truck run without having to hold the switch???
I installed the wiring harness from the 302 ,,, msd ignition ,,, new coil,,,, etc etc etc,,, any ideas????
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Joined: Jun 1999
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From: Comox Valley, Canada
wont stay running'????
What it sounds like is the lack of 12 volts to the coil during start. This is provided, on pre80's trucks anyway and I think the early 80's were the same, by a wire running from the "I" terminal of the ignition relay to the coil.
Well actually not directly to the coil +, it went to a splice which connected 3 wires together. One was a resistor wire coming from the "run" terminal of the igntion switch (provided a lower voltage to coil for constant engine running I beleive to extend coil life). Another went to the coil + (for obvious reasons
). And the third was the 12 volts for staring from the igniton relay "I" (which only has 12 volts on it when the relay is closed). I think the theory of 12 volts from the "I" terminal was for a stronger spark for initial start.
Anyway it sounds like your truck is lacking this 12 volts so trace out the wire from "I" to the coil.
Hope this makes sense.
Sparly
Well actually not directly to the coil +, it went to a splice which connected 3 wires together. One was a resistor wire coming from the "run" terminal of the igntion switch (provided a lower voltage to coil for constant engine running I beleive to extend coil life). Another went to the coil + (for obvious reasons
). And the third was the 12 volts for staring from the igniton relay "I" (which only has 12 volts on it when the relay is closed). I think the theory of 12 volts from the "I" terminal was for a stronger spark for initial start.Anyway it sounds like your truck is lacking this 12 volts so trace out the wire from "I" to the coil.
Hope this makes sense.
Sparly
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wont stay running'????
dynamic, does the engine want to fire when you turn the key to start? and then die when you release the key? If so, the engine is trying to start on the 12v (like Sparky says) but does not have the ballasted 9v to keep running. Make sure you have 7-9v at the coil positive terminal with the key on. If not, you have left a wire loose somewhere between the switch and the coil.
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From: Rhode Island
wont stay running'????
she will run ,, if i hold the key right after the start positon ,, but if i let the key fall to where it belongs ,,, she will die out right away!!!!!
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Joined: Jun 1999
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From: Comox Valley, Canada
wont stay running'????
Have you measured the voltage at the coil + ?
Disconnect the wire there and hook up a voltmeter between the wire and ground. Should have 12 volts when key is turned to start and 9 or so when key is at run.
If you dont have a voltmeter do the same thing with a test light. Light should glow at both start and run, hopefully brighter at the start position.
If you dont have voltage at the run posion or the light doesn't glow the problem is between the coil + and the ignition switch. Broken wire, igntion switch not adjusrted properly or dead igntion switch. Being as it worked before I more guess a wire is the possible problem. But hey switches have been known to die instantly in my experience.
Good luck.
Sparky
Disconnect the wire there and hook up a voltmeter between the wire and ground. Should have 12 volts when key is turned to start and 9 or so when key is at run.
If you dont have a voltmeter do the same thing with a test light. Light should glow at both start and run, hopefully brighter at the start position.
If you dont have voltage at the run posion or the light doesn't glow the problem is between the coil + and the ignition switch. Broken wire, igntion switch not adjusrted properly or dead igntion switch. Being as it worked before I more guess a wire is the possible problem. But hey switches have been known to die instantly in my experience.
Good luck.
Sparky
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