Cranking isssues

[reddishdsb]

71 duster 225 does not want to crank, but new ballast resistor on it ohms at 1.7 ohms.
Got it to crank and run with a jumper wire to positive side of the coil, when I turned car off it continued to run, any ideas? coil switch or something else?

 

[67Dart273]

Let's define "crank."

Correct term for "crank" is "motor turns with the starter."


I suspect you mean "start." Is that what you are saying, it turns over on the starter but does not fire or start?

===============================

Now, it won't shut off. Are you saying the key is off, the jumper is disconnected and it still runs?

 

[TrailBeast]

Let's define "crank."

Correct term for "crank" is "motor turns with the starter."


I suspect you mean "start." Is that what you are saying, it turns over on the starter but does not fire or start?

===============================

Now, it won't shut off. Are you saying the key is off, the jumper is disconnected and it still runs?

I think I have you figured out Del.
You my friend are a glutton for punishment, yea that's it.

 

[reddishdsb]

I agree! Yeah lets say it will not start and run without the jumper wire and it continued to run when I turned the key off with the jumper wire still connected, once I disconnected the jumper it did quit running!

 

[67Dart273]

OK well that's the answer to that. Your jumper is bypassing the key, so of course it would run that way

Ok, what DOES it do with everything "normal" and using the key?

Does it fire or try to start?

Have you checked the spark at the coil wire while using the key to crank? (Use a spark tester, or even just "rig" a spark plug to the coil wire. You can even "rob" one plug wire for that purpose temporarily

Here's the thing

Mopars have TWO sources of ignition power

When the car is in "run" the ignition switch supplies power to the coil through the ballast. This is the traditional dark blue wire, and slang usually "ignition run" or "switched ignition." On the wiring diagams, Ma calls it "IGN 1"

THIS POWER goes OFF when you twist the key to start

During "start" the key supplies power to the coil directly. This comes off the ign switch on a brown wire, through the bulkhead connector, and to the coil + side of the ballast. Ma calls this "bypass" circuit "IGN 2"

It's purpose is to do the same thing as your jumper wire---give you a hot spark for starting.

=====================================

Another thing you can try,................you have a test light or multimeter?

Make two tests.

Hook your meter / light to coil + and ground. Turn the key to run. If you get 12V or a very bright test lamp, "bump" the engine a little bit which should cause the points to close.

Now, the meter should read MUCH less than 12V. Anywhere between 5 and 10 volts somewhere, or the lamp should be somewhat dim.

Next, crank the engine using the key. The meter should read AT LEAST 10V or higher during cranking. The test lamp should get brighter than before.

If you have OK voltage in one test but not the other, check that circuit, IE run or start, IGN 1 or IGN2

HAVE YOU got a service manual yet?

Download them here

http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617

More manuals and other great info here

http://www.mymopar.com/index.php?pid=31

 

[BarelyaV-8]

OK well that's the answer to that. Your jumper is bypassing the key, so of course it would run that way

Ok, what DOES it do with everything "normal" and using the key?

Does it fire or try to start?

Have you checked the spark at the coil wire while using the key to crank? (Use a spark tester, or even just "rig" a spark plug to the coil wire. You can even "rob" one plug wire for that purpose temporarily

Here's the thing

Mopars have TWO sources of ignition power

When the car is in "run" the ignition switch supplies power to the coil through the ballast. This is the traditional dark blue wire, and slang usually "ignition run" or "switched ignition." On the wiring diagams, Ma calls it "IGN 1"

THIS POWER goes OFF when you twist the key to start

During "start" the key supplies power to the coil directly. This comes off the ign switch on a brown wire, through the bulkhead connector, and to the coil + side of the ballast. Ma calls this "bypass" circuit "IGN 2"

It's purpose is to do the same thing as your jumper wire---give you a hot spark for starting.

=====================================

Another thing you can try,................you have a test light or multimeter?

Make two tests.

Hook your meter / light to coil + and ground. Turn the key to run. If you get 12V or a very bright test lamp, "bump" the engine a little bit which should cause the points to close.

Now, the meter should read MUCH less than 12V. Anywhere between 5 and 10 volts somewhere, or the lamp should be somewhat dim.

Next, crank the engine using the key. The meter should read AT LEAST 10V or higher during cranking. The test lamp should get brighter than before.

If you have OK voltage in one test but not the other, check that circuit, IE run or start, IGN 1 or IGN2

HAVE YOU got a service manual yet?

Download them here

http://www.forabodiesonly.com/mopar/showthread.php?p=1970088617

More manuals and other great info here

http://www.mymopar.com/index.php?pid=31

Which side of the ballistic resistor is positive and which is negative it is not marked on the one I just picked up from napa? I have one wire that is blue it's a single wire and the other is blue wire and a brown wire? Sorry to jump in but you seem to know your stuff?

 

[67Dart273]

It's not exactly neg and pos. It's the "switch" side and the "coil" side. The side with the brown should be the coil side.

Check them both.

With the key in run

and the points closed

You should have "close to battery" on the switch side and lower voltage on the coil side.

If you have "close to battery" on both sides either the points are open (rotate the engine)