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Today went after electrical side to try and find cause of no start. Removed distributor, did ohm test to insure positive from coil was not grounding to base. The only time it did was, as expected, when points closed. Hot wired new modern 6 volt coil. Check all plugs for spark, good,so assume cap and rotor are good? Then checked KV reading at each plug and on coil wire. This to me at lest, seems very strange. The plug wire readings ranged from 1.9 to 11.3 KV? (New plug wires and plugs) The coil wire both modern and new old stock had about the same spread of 4.2 to 20KV, this can't be right. Checked my 1985 Bronco and the plug wires ranged from 20-30KV. I know the coil is 12volts but wanted to be sure meter was working properly. Any ideas on what's going on?

I would verify the voltage at the coil terminal coming from ign switch. It should be around 6.3 to ground when sitting -- maybe slightly less if points are closed -- and should stay at least 5v or higher when the engine is cranking. If something is causing the voltage to drop much below 4.5 the spark will be very poor or non-existant. Also with new plug wires and plugs, assume both are all metal and not the resistance types.

If that voltage is good, you could also check the terminal going to dist for voltage to ground. When points are open you should have the same 6.3v and if points are closed, close to 0 volts. If the voltage when points are closed is higher that would indicate a poor ground to dist or possibly oxidized points.

Battery is low due to all cranking so voltage is down to 6.0. Currently charging with pulse type charger as I have an Optima battery. Coil + to ground is 6.0volts and ohms across primary coil is 1.5, so, think coil is OK. Cranking drops coil voltage to fluctuate between 4.2 and 4.6! New Champion plugs and new carbon fiber wires. Couldn't find any solid wires in town and was told by many the 7mm carbon wires are OK. When points are closed, volts is 1.2 volts or so? One point is that I had the distributor rebuilt and was told the ground wire from the plate to the point base was unnecessary and was not reinstalled, maybe I should reinstall?

Ground wire within the distributor between the moveable and fixed plate is essential! Otherwise you're trying to complete a ground thru a greased pivot or ball bearing. And the lead constantly flexes so it must be correct for the application, beryllium copper. Simple copper will soon fatigue and fracture.

The low battery will affect the top end. My battery is a bit low too and the 47 356 is currently holding around 4.9v when cranking so a bit low. The solenoid is chattering too so put mine on a charger and will check again tomorrow.

Your terminal to dist voltage is too high if the engine was stationary. I should have made clear that voltage can't be checked well when cranking so hopefully yours was stationary. If not it needs to be checked again. With my engine bumped so points are open I am reading battery voltage at almost 6.3v. When engine is bumped again so points are closed, the voltage drops to about 130 millivolts or essentially a dead short -- as it should when points are closing to solid ground.

If yours can't reach near that 0 point then I would place the ground on the plate again as a test. You can see if it is needed by popping the cap and with points closed, measure the voltage without a ground. Then with meter still connected touch a jumper from dist case to the plate or the stationary side of points. If voltage drops significantly as you make the connection you need the ground wire.

Not sure which dist you have but some of the plates do mount thru loose bearings so anything not reaching ground directly usually has a jumper for the solid connection.

Thanks, will up date tomorrow.
Bill

OK, here's the latest. Battery voltage now 6.29. Voltage at stationary side of points 6.26 (points open). Voltage at each lobe (points Closed) .055-.080. Then put jumper wire form stationary side of points to distributor body .116 volts. So, if I under stand this correctly, this part is OK? Now the plug wires,was unable to find wire spark plug wires so had to go with carbon fiber wires. May have installed them wrong, get 5.0 ohm reading on coil wire and 14 ohms on the longest wire. When striping wires for installation removed outer and insulating cover but left on inner cover to protect very tiny carbon fibers, wonder if this maybe the source of my problems?

The .116 voltage sounds reasonable but not quite sure what you meant by the other numbers at each lobe. If you mean at the dist terminal, points closed, and it was a consistent .116v with or without the extra ground wire connected then yes, that sounds OK. The only caveat is one O_D brought up in that if the plate rotates and the ground is being supplied thru bearings then that number could change.

Just FYI. On a fully charged battery, right after removing the charger and using 00 bat cables, my 356 had 6.43v at the coil ign feed side. It dropped to 5.2v when cranking so my memory of voltage not dropping below about 5v is confirmed. No change on the dist side. When points were closed it is a few millivolts over 0v to ground.

Those resistance numbers on the cables sound high but someone else will have to comment on the proper way to make up the resistor cables. Don't think I ever messed with them. IMO, even if the cables are perfect, any resistance is not very good for a 6v system. A 12v system putting out something in the neighborhood of 35-40K or even more with specialty coils can tolerate some loss but a 6v system is normally in the 20-25K range and doesn't have much to spare. Packard says the 6v coil can put out up to 25K but I do believe that would be under ideal conditions so figure probably 2-3K less in average use and older connections. The added resistance of the cables would reduce that voltage more by the time it reaches the plugs.

If the old spark plug wires are serviceable, try replacing the new ones with the old ones. You can check them before installing. And, yes install a ground wire from the plate to the housing. You can use a copper wire temporarily until a correct one can be located.

(o{}o)

It's alive! Repaired old plug wires, 2 were dead, and re-installed. Engine started and ran for about 10 minutes then died. Surprised it ran at all, as looking under car for a lock washer found spring and carbon tip for distributor coil post! Re-installed and ran great no more dying. Then attached overdrive wire to distributor and wouldn't start. Went to remove overdrive wire from distributor and wire to coil fell off lug at coil terminal! Goes to show that good test results (ohm and voltage tests) on this wire were not conclusive, must have been just a few strands hiding under the insulation holding it on. Repaired and now starts as is should. Looking for roll of spark plug wire to make up new set as KV readings, although much higher than with carbon wire,still vary. Some wires are in the 20-30KV range while others are in the 8-10KV range. By the way, the distributor is a 1954 with the vacuum advance turning the distributor body not just the base plate. The old (non reinstalled) ground wire connected the point base to the plate base, not to the distributor body. As you can see from my previous post the mini voltage across the points is lower than it is across the points and distributor body. So I think were good unless there is something I not getting right?