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Diagnosing a no start no spark problem has raised a few questions and a need for opinions about some assumptions I'm making as well as advice or guidance from anyone who has been down this path.

The car:
1940 160 Super Eight Club Sedan model 1803
Replacement engine is a "G" series 356 making the engine a 1948/49 Series 22

The problem:
No spark off spark plug wires
No spark off secondary/high tension lead from coil
Engine cranks but will not fire
Gas flows to the carburetor
Problem happened suddenly after driving then stopping for gas and would not restart

My assumptions:
I believe the coil is original from the 1940 18th series (see pictures below)
I'm guessing the distributor came with the replacement engine and would be a 22nd series

My questions/problems:
I want to check and/or replace ignition system components - points, condenser, rotor, distributor cap, coil but want to validate the problem part so I know what really went wrong.

1) Before replacing any parts, is there any problem mixing different vintage electrical components? Specifically, a 1940 vintage coil with a 1948 vintage distributor/points/condenser. They are supposedly already mixed but I really don't know what the previous owner put in the system. I need to understand this in case the coil is good and remains on the car but regular maintenance items in the distributor need replacing.

2) I know a failed coil is not usually the problem in these cases but I want to check it out anyway. I've read the forum posts of others who replaced the coil and it looks like an unpleasant project to get the armored cable disconnected from the ignition switch so I"d like to know if the coil is bad before going through the gymnastics of replacing it. I can't totally isolate the coil without disconnecting the armored cable from the switch which creates a bit of a chicken and the egg situation.

Can I test the coil while still in the car and attached to the ignition switch or will the switch connection affect the ohms reading I will get? When I test the secondary circuit using an ohmmeter connected to the positive terminal and the central terminal I get a reading of 3500 which seems weak but I don't know if being connected to the switch impacts the test result.

3) With the coil still in the car, I don't understand how to test the primary circuit since there is no negative terminal on the top of the coil. Where do I connect the ohmmeter negative lead for the primary circuit test?

4) My research shows the expected primary and secondary circuit readings for a good coil test should be Primary = 1.2 to 1.5 ohms and Secondary 9,000 to 11,000 ohms (same for both 1940 and 1948/49 coil versions). Can anyone validate this?

5) If I need to replace parts I assume I should match everything to the 22nd series engine. But if the coil is indeed original and still good should the ignition condenser match the 1940 coil or the 1948 distributor - or doesn't it matter?

6) What happens if the condenser is a mismatch for other components? Just poor performance and/or premature failure of the points?

7) My research shows the condenser should be .18 to .25 microfarads and 200 to 300 volts (same for both 1940 and 1948/49 versions). Can anyone validate this? I can't seem to find such specs on any NAPA/AutoZone offered units - just generic descriptions. How do you determine if what they offer meets the needed spec? Not a problem if I should use the 22nd series parts since there are a few in the parts cross reference forum section.

Apologies for the litany of questions but I'm still trying to figure out the full genealogy of this car and each mechanical and electrical repair raises a bunch of compatibility questions because of swapped components crossing multiple Packard Series not to mention previous owner modifications.

Any and all inputs and assistance is greatly appreciated.

Have you visually inspected your rotor, cap, and points and checked the point gap?
With the distributor clip off in the second picture it looks like you might have.

Yes, rotor, points, distributor cap and point gap all good. Car was running fine until I stopped for gas and it would not restart. I may just change them all out anyway while I have everything apart and testing things out.

Do a thorough check of the primary system with a voltmeter. Power to your points with ignition on? Then trace through to your coil.

Don't use a voltmeter on the secondary system as you will damage it.

Quote:
A capacitor compensates for voltage peaks. A malfunctioning or incorrectly sized capacitor will cause premature wear of the points. Ignition problems, an engine that won't start and rough running are symptoms of bad points and a malfunctioning capacitor.

Attach file:

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  capacitor.jpg (175.96 KB)

-> How to test a capacitor with a multimeter (make sure that the points are open).

Does the distributor have a resistor rotor in it? If so, that will need to be checked. I (for better or worse) get rid of them. Looks like you have resistor wires on anyway. I had the same problem as you about 35-40 years ago at the gas station, filled up and no start... no spark. Then, as now, I keep a spare points and condenser in the glove box....it was the condenser. But, that's not saying your problem is. Good luck, PB.

I think I've answered my questions 2 & 3. Looks like the bottom of the coil is detachable to reveal the negative terminal connection and also allow the removal of the coil body. If that's true, I can test both primary and secondary circuits on the bench. I'll try that before attempting to remove the armored cable connection at the ignition switch.

packardinfo.com

If the capacitor did not suddenly fail, something else that can happen fairly quickly resulting in no spark is points burning or oxidizing because the key was left on when the points were in a closed position. Sustained current flow thru the coil and closed points causes them to overheat which can form an insulating coat over the contact surface. That issue can be a too common occurrence in cars with ign switches having only two positions and may be the reason so many radios of the era were wired with constant power -- so they could be played when the car was parked without having the ign switch turned on.

To quickly check the coil for spark you can disconnect the high tension wire from the distributor center hole and place the end near the block -- maybe 1/8" or so away. Also disconnect the primary wire coming from the coil at the distributor terminal and then scratch the wire terminal against something well grounded on the block. Make sure it is a good ground connection and not just paint. As you break the connection between wire and ground the coil should produce a spark jumping to the block at the end of the high tension lead. CAUTION: If you do this test use something insulated to hold the wire terminal and not your bare fingers as you touch it to the block. If you use bare fingers there is every chance you will get an unpleasant jolt.

Also, insulated against 20kV. E.g. not pliers with plastidipped handles (ask me how I know).