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airlifter

Jedi Hopeful
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I posted earlier about the coil problem. I changed the coil today. The new coil is by Stadard and does not require a ballast resistor.

Now I do not have any spark at all. Not from the coil and none across the breaker points. I checked all of the connections in the dist. I have 12 volts at the positive side of the coil. The resistance across the low voltage side of the cois is 3.8 ohms. (I checked with two different meters)

What next????
 
Turn the engine until the points are closed, check the voltage at the points terminal on the coil. Also double-check the voltage at the hot terminal.

If you find 12v across the coil terminals, then turn until the points are open, and check again.
 
Check the little ground wire inside the distributor, it's covered by brown cloth and can break. Check with a OHM meter.

Wayne
 
I had 12 volts acroll the terminals with the points open and closed.

The small ground wire was intact.

I know I am missing something simple and/or dumb but I seem to be having a brain freeze.
 
Was the coil the only thing you messed with since it was running?

The White/Black wire from the coil to the distributor is also prone to internal breakage -- a failure that is not always evident on visual inspection.
 
Yes, the coil was the only thing that I missed with. When I checked the voltage at the coil terminals I checked it at the terminal in the dist.

I read 3.8 ohms across the terminals of the coil. Is this about right?
 
airlifter said:
I had <span style="font-weight: bold">12 volts</span> acroll the terminals with the <span style="font-weight: bold">points open and closed</span>.
Click to expand...

12V on both sides of the coil with the points open or closed implies a break in continuity somewhere after the coil. Since you said you measured the 12V at the points IN the distributor, that suggests two things
1) You set the points with the heel block NOT on the peak of one of the four lobe cam below the rotor, or
2) Somehow the points do not have an earth connection.

3.8 Ohms across the coil can be OK. The value varies from coil to coil. The Bosch Blue coils that I use typically measure 3.8 Ohms.
 
dklawson said:
12V on both sides of the coil
Click to expand...

On the other hand, if you find 12V <span style="text-decoration: underline">across </span>the coil all the time (measuring between the two side posts rather than from each post to ground), it implies that either the points are not opening or the wire to them is shorted to ground somehow. One of the most common causes of that is mis-assembling the wire to the points inside the distributor ... remember the wires go on first and then the insulator, not the other way around. (If I had a nickel ...)

Another possibility might be that your condenser decided it didn't like the new coil, and failed shorted.
 
I agree. Sorry if I implied measuring across the coil. That's not at all what I intended that sentence to sound like or imply. My intent was how to interpret finding 12V between ground and each coil terminal (by itself).
 
No worries, Doug, I just wanted to be clear since I was talking about measuring across the coil.
 
I told you it would be something simple and dumb.


TR3driver said:
dklawson said:
12V on both sides of the coil
Click to expand...

On the other hand, if you find 12V <span style="text-decoration: underline">across </span>the coil all the time (measuring between the two side posts rather than from each post to ground), it implies that either the points are not opening or the wire to them is shorted to ground somehow. One of the most common causes of that is mis-assembling the wire to the points inside the distributor ... remember the wires go on first and then the insulator, not the other way around. (If I had a nickel ...)

Another possibility might be that your condenser decided it didn't like the new coil, and failed shorted.
Click to expand...


I measured both ways. The problem was stareing me in the face and I did not see it. DUH!!!



Thanks again, Pete
 
Like the rest of us have never done that ... :laugh:
 
My favorite is when I forget to put the rotor back in the dizzy. I am embarrassed to say how many times I've done that over the years.
 
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