No spark to plugs

[FrankWest]

Model B 1933
Installed new starter
Installed petronix ignition coil <flame thrower..RIGHT?
Cleaned points
What next?
Can I electrically verify that the lower distributer plate is NOT shorted to the top plate?
Continuity test with my multimeter. Where would i test from? Points to distributer case?

[drolston]

With ignition switch on, check voltage at the ignition switch side of the coil. If the points are open, it should read battery voltage (-6V ?). With the points closed it should read about -4.5V. Turn the engine over by hand and watch the voltage switch between those two values. Now try it by cranking using the starter. The voltates should drop a little, not a lot, due to the load on the battery caused by the starter. If the voltages drop a lot, double check your grounding with heavy duty cables battery to starter, battery for ground, and ground to engine block. If the grounds are good, suspect the battery. Report back.

[FrankWest]

before my problems began, when I turned the ignition key to the on position, I would see a fluctuation in the vehicle ammeter. Also, when I stepped on the ignition button I would also see a fluctuation in the ammeter. I no longer see those fluctuations.

[Als48]

If you dont see that voltage fluctuation on the dash volt meter, it's usually the points from my experience. Try to be a little more aggressive at cleaning /filing the points. Sometimes that corrosion/scale is hard to get off and it can keep the points from making good contact.

Al Hook

[FrankWest]

thanks.
should i use 1200 grit emery board

[Als48]

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That sounds good, but it might take a more aggressive grit (100-250?) to get throught the baked on deposits. If the points are pitted very much, you might as well change them.

Al hook

[drolston]

The ballast resistor is about 1.5 Ohms. The primary windings are a bit less than 1 Ohm. Asuuming 2.25 Ohms total, when the points are closed that circuit will draw (I = V/R) about 2.6 amps. That is enough to wiggle the ammeter. No wiggle means no current flow. Several things can cause no current flow, and burned or stuck open points is the last thing in the chain. Start by checking that you have battery voltage at the coil, where the red wire attaches. If yes, fix the points. If you do not have a volt meter, get one; a cheap analog one (with a needle) - not digital (with and LED). If no voltage at the coil, do the following:

Assuming you are still 6 volt , positive ground:
1) red/positive lead from voltmeter to a good ground (bare metal on dash, or column)
2) With the ignition switch off, toucn black lead to either terminal on the back of the ignition switch. One of them should show 6 volts.
3) If neither, check to be sure the headlights work, confirming battery voltage is getting to the ammeter.
4) If the lights work, find the break or disconnect inthe hot wire (Yellow/black, I think) coming from the ammeter to the ignition switch.

5) Turn the ignition switch on. You should find 6 volts on both terminals on the back of the ignition switch.
6) If one is still zero volts, repair the ignition switch. They can wear out and fail.
7) If both sides have 6 volts, find the ballast resistor; a wire wound thing mounted on the firewall behind the dash. You should have 6 volts on one side, and at least 4 volts on the other side. If not, replace the ballast resistor if cleaning and tightening the connections does not fix the problem.
8) If you have voltage on both sides of the ballast resistor, find the break or disconnect in the wire going from there to the ignition coil. Should be a red wire.

[FrankWest]

wow drolston, that is great stuff..Thanks for taking the time to help.
I will follow these instructions to trace what is wrong with my car.

[Donaldoster]

condenser?

[FrankWest]

I turned on the headlight and they went on so I switched them off and turned them on again and they did NOT go on?

[FrankWest]

The horn sounds a little weak. The battery was just charged.

[TJ]

How old is the battery?

[FrankWest]

Brand new as of 3 days ago. Fully charged.

[drolston]

Intermittant lights and weak horn indicates battery connection or ground problem.

Starting with the battery terminals, double check all positive and negative battery connections for tight and corrosion free.

Does the wire to the ammeter on a '33 go through a loop or connect to a post? If connected to a post, clean and tighten the connections.

[FrankWest]

The ammeter is connected with 2 leads, I tightened them down, they were a little lose.
The horn sounds normal now and the headlights work, high and low beam and are not intermittent, but I still don't see the ammeter jiggle when I turn the key or step on the starter. Still no spark to the plugs.

[rockfla]

Frank
Have you checked the hot wire to the coil and with the key ON what is the Voltage to the coil? OR do you have voltage at the coil with the key on?? Simple first test BEFORE moving forward. are you FOR SURE getting power to the coil??? Drolston gave you pretty clear instructions and nowhere since the start of your post have we seen ANY voltage information from any of the suggested point of concern.....from the ballast resistor, ignition switch, coil, ammeter???? you CANNOT get spark IF you are not getting as close to 6V's at all the above locations!!!!! OBVIOUSLY the coil being the MAIN one!!!

[FrankWest]

I will check the voltage to the coil now. In and out.
I don't think my car ,1933 model B, has a ballast resistor?

[drolston]

The starter current does not run through the ammeter. When you said "in and out", what did you mean. The voltage at the coil is intermittant? If so, suspect a flakey ignition switch. Try Steps 4, 5 amd 6. If no ballast resistor, just skip Step 7.

[Flathead Fever]

Did this engine run before the Petrionix distributer was installed.

Your ammeter should have a movement on the gauge while the points are closed, and current is flowing. If there is no movement it could just be that the points are open.

If you have voltage to the points and they break open and closed when it's rotated, then I would check the coil. It's pretty common for them to fail, but before you do that you need make sure the carb is squirting fuel in there and it sounds normal when you crank it. If it's stripped a timing gear or broke a timing belt it will sound noticeably different while cranking.

No spark.

1. Check the available voltage to the distributer with the points open. You need to make
sure, you have the correct coil with the correct voltage to it. They are all different so
you need to find out which coil you have and the voltage it was designed to run on.
2. Make sure the points are filed smooth and have the proper gap.
3 Make sure you have power to the points and none of internals on the
distributers are shorted out.
4. Check the condenser resistance.
5. Check the rotor for cracks and the cap, Look at the pieces real close.
6. If that's good, check the available voltage to the coil. Check it across the resistor if it has
one. Make sure you have the proper available voltage to the coil with the points open or
disconnect the wire coming from the key and check the voltage.
7. While it's cranking make sure the distributor is rotating. At work we had distributers
break the roll pins that hold on the drive gears and the distributer won't rotate. Check it
for excessive side play
8. Check the coil wire resistance. See if its sparks holding it away from a ground.
9. Make sure the distributer is installed correctly.
10. if all that's good then it's probably the coil. Do a resistance check on it.

I was a mechanic for 30 years during the points era on a fleet of 400 phone company vehicles. Like I said, the very first thing you do is make sure the carb is squirting fuel in there and it sounds normal when you crank it. If it stripped a timing gear or broke timing belt it will sound noticeably different, like it has no compression. Money was no object, we looked in the vehicles records to see when the points were last replaced and if it's been a while we replace everything because it needed it needs it anyway, the plugs, points, condenser. rotor, cap and wires. 90% of the time that fixed it. If the vehicle was due for a tune-up, we didn't even try to diagnose it because it needed all that stuff anyway. When it didn't fix it than we broke out the voltmeter and compression gauge and went hunting. I actually enjoyed finding the strange stuff that broke, it was fun since I got paid the same if I was diagnosing or changing oil.

[FrankWest]

I can't read any voltages out of my coil. Could a bad condenser knock everything out?