engine starting issues (resolved)

[dixiedog]

can someone educate me on the ballost resistor?  I have a 4 plug for electronic ignition.  I am trying to get it wire for my car with no luck.  Is ther a - or + on the resiostor and if so how can I tell?  I am totally oblivious to wiring but am learning.  The guy that wired my car had a jump wire through the firewall to a hot wire.  I took it off, replaced the wiring harness (due to it being butchered up)and add anelectronic conversion harness from year one.  He also had a wire from the main box going to the resistor (looks to me like it was the brake warning light switch wire from what I can tell).  I don't understand that either.  Before I changed the harness I unpluged that wire and the car would run but it didn't want to start and when it did it was missing awful.  I am in a quandry here and want to give up but I won't.  Thanks, depressed Dano

[MEK-Dangerfield]

There is no "+" or "-" side to resistors.

Sorry I don't have any suggestions for you.

[dodj]

The ballast resistor is two parallel resistors. One side is 5.0 ohms, the other is 1.2 ohms. At one end the resistors are connected together with the blue (run) wire from your ign switch. At the other end, you connect the brown (start) wire from the ign sw. which then continues on to the + side of the coil. The other dk grn wire goes from the other resistor to the ecu. The brown wire is connected to the 1.2 ohm resistor if I remember correctly.

[72 cuda]

Dixie dawg,
to my understanding (which is very limited)a 4 prong ballast resistor works kinda like this:

The top poles is for the  cranking mode which  it allows more fire when is starting.
The lower poles are for the (run) position it reduces the fire so as not to burn the points.

One wire comes off the start position on the key switch so when you hit the key it throws 12volts
to the coil.
Then when you let off the switch and it comes to the run position then the second wire from the run position then runs to the lower poles(  normally the bottom ) position on the ballast resister reduces the voltage so as not to burn the points up.

Chryco and many others here can tell you how to ohm the resistor to tell which pole is which.
This is the basics of a ballast resistor(I think).
I hope this helps.
These guys know a lot more about it than I do.
This is why I tried brake it down to basics.
Because most of there explanations are beyond my understanding, they just Know so much more than most of us.
Mark

[dixiedog]

Thanks Scott and Mark that does help.  My wiring was messed up when I got my car back from the shop.  The wiring was originally for a points engine.  I put an engine in it with electronic ignition.  The guy that wired it could not get it going, he had to run a jump wire from the ballost thru the firewall to get it to fire.  Then it would only fire when you let go of the key to the run position, it would not start with the key in the start position.  There was a wire from the main block running to the resistor also (as best as I could figure it was the brake warning switch wire).  I got an original harness in very good condition for a 440 Challenger and order an electronic conversion kit from Year One.  Put that on my car with the help of a friend from the board here.  Not getting any fire to the coil.  I will check to see if the wires are correct on the ballost, I don't believe they are.  Will get back with you guys when I know more.  Thanks, danny

[Chryco Psycho]

there is no need for a 4 pin ballast , a 2 pin works fine , the way this is wired is there is a blue wire from the ign switch for the 12 v run feed , this wires to the the ballast , on the other end is a brown wire from the ign switch to bypass the ballast in start position  allow the coil to produce a hotter spark while starting  , the other side of the 4 pin ballast drops voltage to the ECU , after about 74 all ECUs eliminated the 5th pin & moved the resister inside the ECU

[dixiedog]

Thanks guys, after much work I got it starting as it should.  I used a wiring harness I bought on e-bag and an electronic conversion kit from year one.  Used my wiring diagrams and retraced everthing, had a couple of wires not correct.  Now she cranks right up .  I still have an issue with the alt not charging.  I had it tested and it is good.  Any suggestions on where to start?  Thanks again, Danny

[ShelbyDogg]

Did you have the voltage regulator tested too?

[dixiedog]

This may be a stupid question ShelbyDogg but where is the voltage regulator?  I was thinking it was internal to the alt.  Thanks, Danny

[ShelbyDogg]

Voltage regulator is on the firewall, above the engine, with the triangle looking plug, that contains 2 pins.  This thing has to have a solid ground. clean off a little paint, then tighten that thing with a star washer and put a nut behind the firewall inside the cowl vent.  Get a spare one from a junk yard or auto parts, then keep it in the glove box with your spare ballast resistor.

[dixiedog]

Okay, I know what you are referring to now.  Yes mine has one it is new and the engine bay has recently been painted.  I have heard some of you guys say to keep an extra ballost so I guess I will keep an extra of both.  I will do as suggested and let you know.  I can't say thank you enough for the help I have received from the guys on this sight.  Danny

[ShelbyDogg]

There are only 2 wires on that thing. The outside one goes right to one of the fields on the alternator. The top blue one goes to the other alternator field and also 12v while the key is in the run position. The main common issue is the bad ground.

[smallblocksrock]

Regarding the alternator not charging the battery.  I had a similar issue recently with a new alternator and voltage regulator.   The car would run, then die when I drove it around the block.  I had to jump start it to get it home.   I looked over the wiring a few time and then swapped the field terminals on the alternator.  It charges fine now.

[dixiedog]

I tried the ground, making sure it had a good ground.  The alt. is still not charging.  I think I may get another voltage regulator and see what that does.   Thanks, Danny

[ShelbyDogg]

A common weak spot is the Big black wire going through the firewall at the bulkhead connector. It burns up at the connector.  To bypass it hook a big jumper cable between the positive battery terminal and the big terminal on the alternator, while watching a voltmeter hooked  across the battery. It should jump up to 13-15 volts.  Try this before you buy the voltage regulator.   (get a spare anyway)