ignition switch question
- Thread starter Darren
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KitCarlson
Well-Known Member
By using clip leads on a voltmeter check for voltage at coil + and ground while cranking. Set meter on cowl where you can see it. It should read about 12V, and reduce when the engine is running if you have a standard ballast resistor system.
KitCarlson
Well-Known Member
If the coil voltage measures good, check to see if the choke is setting closed after a single throttle press and release, at temperatures below 68F.
Rate now it starts good so i would imagine the coil voltage is good. And the choke is setting closed after one throttle press and release. (Is that normal ?)It's weird for some reseason it probably won't start tomorrow morning. ..
KitCarlson
Well-Known Member
Yes, that is the way most chokes are set and fast idle cam is activated. Once engine starts, vacuum on the choke pull-off opens the choke some to keep the engine running.
blown71duster
Well-Known Member
You may want to check the carb when the engine is cold to make sure it's getting a good shot of gas from the Accelerator Pump .
Sometimes the carb bowl will drain overnight and will cause a no/hard start until the fuel pump fills the carb back up with gas.
That is assuming you have good spark during cranking.
Sometimes the carb bowl will drain overnight and will cause a no/hard start until the fuel pump fills the carb back up with gas.
That is assuming you have good spark during cranking.
We're supposed to get a full 12 volts to the coil when starting which is most critical for a stone cold engine. Once started the ballast resistor reduces the voltage to the coil in run so it doesn't overheat. A warmed engine will start on the reduced voltage. The above is true for points or electronic ignition but, electronic ignition module does need a full 12 volts at all times to function properly.
There are some heavy gauge wires to the starter so a good battery can spin it fine while the smaller gauge wires and poor connections can lower the voltage supplied to everything else. Bottom line... check supplied voltage to the ignition box and at the coil. My best guess is you had noticed the typical signs of a weak electrical system ( headlights dim at idle, etc.. ) before installing the electronic ignition.
The ignition switch can be the culprit or location of a weak connection. Must be 12 volts going into it and out of it again. Connector at that switch has 2 blue wires crimped into one terminal. One of those blue wires goes to the instrument panel only. The other goes out through the bulkhead and branches to feed everything under the hood that needs 12 volts, charging system, ignition system, and the horn.
There are some heavy gauge wires to the starter so a good battery can spin it fine while the smaller gauge wires and poor connections can lower the voltage supplied to everything else. Bottom line... check supplied voltage to the ignition box and at the coil. My best guess is you had noticed the typical signs of a weak electrical system ( headlights dim at idle, etc.. ) before installing the electronic ignition.
The ignition switch can be the culprit or location of a weak connection. Must be 12 volts going into it and out of it again. Connector at that switch has 2 blue wires crimped into one terminal. One of those blue wires goes to the instrument panel only. The other goes out through the bulkhead and branches to feed everything under the hood that needs 12 volts, charging system, ignition system, and the horn.
yes sir, the yellow wire at switch connector signals the starter relay and nothing more. Less than 12 volts will operate that relay too.
had a similar issue and it turned out to be a bad pickup coil in the distributor. I'd swap the coil for a known good unit, see if it persists, and if it does, then look at a new distributor pickup. I don't know how sloppy your key cylinder is, i suppose thats possible...but that doesn't seem to be a common cause around here of the symptoms you are describing. especially with intermittent starting as a result of it sitting.
http://www.autozone.com/ignition-tu...76/8-cylinders-l-5-9l-4bl-hp/113852_0_0_7049/
http://www.autozone.com/ignition-tu...76/8-cylinders-l-5-9l-4bl-hp/113852_0_0_7049/
Did you check the reluctor gap in the distributor before installing it. It should be .007" or .008" with a brass feeler gauge.
I didn't check one once, and it turned out to be .030" gap and wouldn't start when warm, only cold... #-o :banghead:
No I did not, but it was on my list. It did state that in the installation instructions too.Did you check the reluctor gap in the distributor before installing it. It should be .007" or .008" with a brass feeler gauge.
I didn't check one once, and it turned out to be .030" gap and wouldn't start when warm, only cold... #-o :banghead:
So is it safe to say that a electronic ignition relies more on a fully charged battery then a points ignition?
That is not how I would have put that, but I think you are on the right track
Compare the Mopar electronic to original points, both in "top" shape
Both use the same coil and ballast, essentially
Both form the spark same way, by switching coil to ground
"Good" points MAY have LOWER resistance than the transistor switch in the ECU, and at some point in voltage sag of a discharged battery, the ECU IS going to stop triggering
KitCarlson
Well-Known Member
About spark testing A clamp on timing light will fire with spark, or inline spark testers that show a spark in a gap.
This is why you must make tests. Voltmeter. enough voltage AT the ignition? at least 10.5
Usually if the battery will spin the engine OK, the battery is OK. That does not mean the ignition system is actually getting enough right there at the ignition system.
nm9stheham
Well-Known Member
Yes, that is the best way to test it.. a 1/4" to 3/8" gap to metal. You should do this way for individual plug wires or for the spark wire from the coil.
nm9stheham
Well-Known Member
No, you cannot make that conclusion. Electronic ignitions can (and typically will) work better at lower voltages; depends mostly on the design and coil.
You'll do yourself a favor to to get a voltmeter and start with doing some tests as outlined. I have not seen any symptom you have described that indicates the battery is going out.
Did these issues start after the new electronic ignition system was installed? What system is that? Did you change the coil? We need the info on every new part you installed and if you deleted anything.
WHAT YOU NEED to work on classic car electrical
1.,....FACTORY service manual. Available free at MyMopar and here
http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617
(By the way a couple of the manuals posted over there CAME from here)
Additionally form MyMopar are other wiring diagrams, simplified, but sometimes easier to follow
2......Some alligator clip jumper leads. More difficult now that RadioShich is now gone, LOL
3......A multimeter, available at any parts store, hardware, or Sears
4......Some sort of spark checker, either made from a spark plug or bought, parts store
5.......A 12V test lamp
6........008" (inch not metric) BRASS feeler gauge for the reluctor gap
7........A timing light. I've bought several cheap at garage sales NO excuses!!!
Additionally for tune/ engine run issues.............
8........A compression tester and or leakdown tester
9......A vacuum gauge.
1.,....FACTORY service manual. Available free at MyMopar and here
http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617
(By the way a couple of the manuals posted over there CAME from here)
Additionally form MyMopar are other wiring diagrams, simplified, but sometimes easier to follow
2......Some alligator clip jumper leads. More difficult now that RadioShich is now gone, LOL
3......A multimeter, available at any parts store, hardware, or Sears
4......Some sort of spark checker, either made from a spark plug or bought, parts store
5.......A 12V test lamp
6........008" (inch not metric) BRASS feeler gauge for the reluctor gap
7........A timing light. I've bought several cheap at garage sales NO excuses!!!
Additionally for tune/ engine run issues.............
8........A compression tester and or leakdown tester
9......A vacuum gauge.
New Proform electronic ignition kit, new flame thrower coil, and new pertroix "stock look wires"
Yes problems started after these parts were installed
I did test voltage at coil + when starting car, I read 10 to 11 volts. But I wish I would of done the test when it was not starting. Because today it started lol
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