Starter is not cranking?

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I am at a loss...still. Can't really try much more tonight. My neighbors aren't noise friendly. I am occasionally getting a spark, it's just very very rare.


I bought a new coil...no go. I powered directly to the coil...no go.

I have the positive lead on the coil going to 12V and the negative going to the distributor. I do not however have a voltage when I measure positive to negative terminal, is this normal? I would think I would get 12v. Do I have an issue at the alternator?
 
GupsTateS said:
I am at a loss...still. Can't really try much more tonight. My neighbors aren't noise friendly. I am occasionally getting a spark, it's just very very rare.


I bought a new coil...no go. I powered directly to the coil...no go.

I have the positive lead on the coil going to 12V and the negative going to the distributor. I do not however have a voltage when I measure positive to negative terminal, is this normal? I would think I would get 12v. Do I have an issue at the alternator?
Click to expand...

do you have voltage on + terminal , grounding to the engine?

Is it points???? change the points/condenser or check pick up if electronic.
 
It's a points ignition.

There is voltage on the + terminal if I ground it to the engine or car body. Just not when I "ground" it to the - terminal.
 
Can you clarify my thought process on how the coil, distributor works. Power (12v start/6V run) goes to the positive of the coil. When the points in the distributor close it grounds the negative of the coil, this causes a current to flow in the coil and this is transfered to the the distributor via the center tap.
 
COIL=This is the part that makes high voltage, up to 40,000 volts, for the spark plugs from the low voltage that is supplied to it by the battery. The reason an ignition coil works lies in the physical properties of electrical current. When a current flows through a conductor it generates a magnetic field around the conductor. Conversely, when a conductor is moved through a magnetic field, a voltage will be induced in the conductor. The coil takes advantage of these principles of inductance by winding one coil over the top of another around an iron core. The changing voltage in the primary winding serves as the 'movement' needed to induce a voltage in the secondary winding. The voltage in either winding is proportional to the number of coils in the inductor; if there are more turns in the secondary, its induced voltage will be higher than the voltage in the primary.

When the points close, current through the coil primary increases from zero to maximum in an exponential manner, rapidly at first, then slowing as the current reaches it's maximum value. At low engine speeds, the points are closed long enough to allow the current to reach a higher current level. At higher speeds, the points open before the current has time to reach this maximum level. In fact, at very high speeds, the current may not reach a level high enough to provide sufficient spark, and the engine will begin to miss. This current through the coil builds a magnetic field around the coil. When the points open, the current through the coil is disrupted, and the field collapses. The collapsing field tries to maintain the current through the coil. Without the Condenser, the voltage will rise to a very high value at the points, and arcing will occur.

POINTS= Ignition points are a set of electrical contacts that switch the coil on and off at the proper time. The points are opened and closed by the mechanical action of the distributor shaft lobes pushing on them. The points have a tough job, switching up to eight amps of current many times per second at highway speed. Indeed, as engine speed increases the efficiency of your ignition system decreases, thanks to heating problems and fundamental electrical laws. This declining efficiency has a serious effect on your spark voltage and results in poor high-speed performance, incomplete combustion and other drivability problems.

CONDENSER= Those same principles of inductance create a kind of paradox, because when the points open and the magnetic field collapses it also induces a current in the primary as well. It's not very much because there are only a few windings in the primary, but it's enough to jump a small air-gap, such as the one between the just-opening points in the distributor. That tiny spark is enough to erode metal away from the points and you'll 'burn' the points. It prevents the points from arcing and prevents coil insulation breakdown by limiting the rate of voltage rise at the points.

more detail for ya.
 
Thanks

I think I had it wrong then. Current flows from the positive of the coil through the negative to the distrib when the points are closed and also build up in the coil, and when the "points" open the current that is stored travels through the center tap to the distributor to produce the spark.
 
It's funny. I was just thinking that!! I do not want points.

If I pick up a MSD 6A can i just run that through my coil and to the existing distributor? Would it essentially negate the points being there? Or would I need to buy a new electronic distributor? And would it also remove my ECU from the equation completely as well?
 
I always thought the MSD box worked in conjunction with the electronic ignition... but I have no experience with them... Just HEI and electronic...
 
What would you recommend for a truely electronic ignition? I was just thinking MSD bc someone local has one for sale cheap I could grab tonight and I already have the coil.
 
Great. I actually have an electronic distributor, just remembered that. Does this remove the ECU from the equation?
 
Nope, Not running it now. And the electronic distrib I have is sitting in a box above my garage somewhere.
 
Thanks for the help, I'm going with the electrical. I bought an MSD 6A for 65bucks tonight, used for around 6 months looks new. I have an accel distrib I just put on, it looks good. I'll let you know how it works out. Probably won't have a chance to touch it again till Fri night. Works gonna be busy rest of week!
 
CAR STARTS!! and it sounds much better doing so.

It only starts when the +12v run signal to the MSD is directly to the battery though, I can't seem to figure out where to get it from the ignition circuit. I hooked it to the side of the ballast that has voltage and it doesn't seem to work. Looking at the wiring diagrams right now, but if someone has some advice I'd be more than willing to take it.
 
You need to not only connect the + lead the positve side of the balist resitor, you need to eliminat the resistor by taping all the wires from the resisto together. That will give you a + reading as the key is turned on, and should give spark when turned over. Did you eliminate the original ECU? If you get frustrated Pertronix makes a new pickup that goes inside your eletronic distributor and takes the place of the ballast resistor and ECU. I think their ignitor 2 is 65-85 dollars.

http://www.pertronix.com/default.aspx This is their site, cusomer service is A+. no arogance, just answers.
 
Thanks for all the help, Car is working solid now. For some reason I try to make it more complicated than it needs to be. I just put both leads together as suggested and car starts and stops now obviously both good things.
 
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