I probably should refine my answer a little bit, especially concerning coil voltage. The coil gets 12v + from the switch. Depending on whether the points, or in this case the magnetic pick up, is open or closed there will either be 0 volts or 12 volts on the negative side. In other words when the pickup or points "close" completeing ground it will read zero volts. When they are "open" there will be 12 volts. When it is running and you have a scope on it it will actually spike to somewhere between 200-400 volts due to the coil windings, which after all is basically just a transformer, and when the coil collapses is how you get your 25,000 or so volts at the plug. If you are getting a flicker out of your trouble light on the negative side while cranking it over, I would say the distributor is working and you may just not have enough voltage to get a good spark. Also if this is a SBC they are known to lose distributor ground through the clamp if it is painted or even chrome. The only real ground is through this clamp and even though chrome is a conductor of electricity if there is any oil between the clamp and the dist or block you can end up with a weak ground and cause a no fire situation. Same goes for paint. File the bottom of the clamp and make sure it's clean. I have seen this many times where a chrome clamp had some oil under it and no spark! The other way you can test the coil is to disconnect the distributor from the coil. Run 12v to the positive side and hold you coil wire that would go into the distributor 1/2" or so from a good ground (block or manifold will work). Take a test lead and hook it to the neg side of the coil, quickly strike it to ground and you should get a spark out of the coil lead each time you strike the ground. If not, most likely a bad coil (or bad coil wire)
Just a clarification..... Someone said : The other way you can test the coil is to disconnect the distributor from the coil. Run 12v to the positive side and hold you coil wire that would go into the distributor 1/2" or so from a good ground (block or manifold will work). Take a test lead and hook it to the neg side of the coil, quickly strike it to ground and you should get a spark out of the coil lead each time you strike the ground. If not, most likely a bad coil (or bad coil wire) Note: For this test to be conclusive and work every time a condensor must be used , other wise often times the coil will not spark. Chrysler actually had a wiring diagram using the condensor to make this test tool.
We were able to get the engine started tonight. After adding a couple more grounds and using a jumper wire straight from the + battery to the +coil it fired. Finally. What is the best way to fix the jumper wire issue. I am using the rebel wiring harness fyi. Thanks guys and gals.
Sorry one more question. We had the car running for about 4 minutes of the 20 min cam break in period. Should we re-prime the oiling system or is the run time along with the initial priming sufficient enough to skip that step. Thanks.
Brotherly bump. We only got 4 min into the break in becuase we had m***ive amounts of oil smoke coming from the top of the headers, we shut'er down to discover we had a valve cover leak. By the time we can it all pinned up again, the apartment complex would have been out for blood had we fired it up again...
You'll be fine on the priming issue. It's already primed if you made any oil pressure during that 4 min of run time. Finish the break in period and make sure you've got good oil with Zinc in it or use some additives like ZDDP if it's not a roller.
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