No spark condition

If you have a spark coming out of the secondary wire from the coil and the rotor is turning, I would suspect either the rotor or the cap. They can both develop a hidden crack that when a spark shows up it goes straight to ground. I would substitute another rotor and cap and see what happens.

A friend has a rotor he keeps for show and tell. It looks perfectly functional. You can check it with an ohm meter and it has continuity. Put it in a distributor and it will not work. It apparently has a hair line crack that is not visible from the center connection through to where it sits on the distributor shaft.

Tom Endy
 
Okay I have spark at the plugs now. I thought about what Tom said when he asked did I install the rotor. We all know sometimes we get caught up with troubleshooting and miss the details. I put everything back together and started retesting everything per all the suggestions in this thread. I believe now it is in fact the rotor. I examined it and it appeared to have some moisture as well as some carbon tracks on it. I washed it off with carb cleaner and retested for spark at the plugs. I do have spark now.

On another note regarding spark when I did retest the coil wire, I was unable to get spark if I held the wire 1/4" from ground. I had to hold it more like an 1/8" to see it arc. Maybe a weak coil?? The spark also seemed intermittent. When I stopped cranking the engine it always seemed to throw a nice arc then, timing maybe?. I sprayed the carb with a little starting fluid just to see if it would ignite. It wouldn't try to start until I stopped cranking it then it sputtered briefly

My question here is should I replace the coil or because I now have spark at the plugs I should consider it okay at this point and begin looking at timing the engine correctly.
I do plan on purchasing a new cap, rotor, condensor, and points.

I do want to thank everyone for your assistance, I really appreciate all of your help.

Mike
 
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When I stopped cranking the engine it always seemed to throw a nice arc then,

I would check the voltage while cranking, maybe a bad connection or high starter draw causing
low system voltage and the weak spark while cranking.

Bob
 
Bob C said:
When I stopped cranking the engine it always seemed to throw a nice arc then,

I would check the voltage while cranking, maybe a bad connection or high starter draw causing
low system voltage and the weak spark while cranking.

Bob
Click to expand...

^^^
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I agree. Read it right at the coil post.

I assume the car is still 6 volts. This is one of the drawbacks to 6 volts. All the connections need to be really clean and tight or you lose too many volts when cranking and you get a weak spark.

Double-check the polarity of the coil while you are there. If you are still positive ground, the wire coming off the positive post of the coil needs to be the one that makes its way down to the points.

The coil may be going out. I always assumed that when a coil failed, you got not spark. Hah! I learned on the Blue Ridge Parkway Tour recently (not my car, a friend's) that the coil will just start giving a weak spark, skip the spark on a cylinder now an then, just give you really poor power. With a new coil it is like a new car again.
 
I agree with Bob.
Also you should just try hand cranking it and it might fire right off without the starter drain.
It sounds like the points could be dirty. If you start it by hand cranking, and let it run for a few minutes, the points will probably be OK.
 
The car is still 6 volts with a positive ground. I cleaned all the battery terminal connections, cleaned the battery cable to frame connection, cleaned the connections at the starter motor. The wires to the coil do look a little rough but they do have continuity.

High starter draw, are you suggesting I may still have a starter issue?

To test for cranking voltage, you want me to measure on the positive post on the coil and ground. What voltage is acceptable during cranking?
Thanks
Mike
 
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You'd have to measure on the coil negative post and a good ground (which is +).
While cranking, the coil should still get about 5 volts.
 
Okay here is what i have for voltages.

Voltage at the battery 6.38 this is a new battery
Voltage at the coil 6.37
Voltage at the coil while cranking 4.77-4.80 measure from the negative post on the coil.

The negative side of the coil has a short wire which terminates on the stud on the drivers side of the terminal block. The positive side of the coil has a wire which runs up into the dash.

My first question I guess I need to ask is the coil wired properly?

The voltage dropped under 5 volts at the coil during cranking. Does this mean I should begin looking at the starter being a problem?

Thanks
Mike
 
From what you describe, the coil is wired correctly.
I'll have to check my voltage the next time I crank the engine, but 4.8 seems like it should work OK to start the engine.
Have you tried hand cranking it to fire it up?
 
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Msaby said:
Hand cranking isn't an option for me.

Thanks
Mike
Click to expand...

Can you get someone to hand crank it?
Twice over the years I had to hand crank mine after it sat for months in damp weather. Once it ran for a minute, the points worked good and the electric starter could then be used.
 
Tom, I placed an order yesterday for parts. I order a new dist body, top, rotor, condensor, points set, coil, coil wire, coil wiring, and battery cables. This should rule all these items out. I will have to see then if I can find someone to hand crank the engine for me.

I drained the fuel tank yesterday. I hope to refill it this weekend so it has fresh fuel for start up when my parts arrive.

Thanks
Mike
 
If you think the starter may be still causing issues because of the marginal voltages I will gladly try and have mine rebuilt. I am very determined to get this car running.
 
No. You have enough voltage at the coil to start. If the starter turns the engine over, you are good.

Now that you know you have spark at the plugs, try giving it a shot of starting ether in the carb air inlet instead of choking it.
 
Update....She is now running! I typed a long post on the things I did to finally get it running but when I went to post, it disappeared. Here is the short version.

I found several items that may have caused my problem. I think the biggest issue was the wires on the terminal block were actually reversed. I couldn't believe it, I had to confirm with several resources that the wires were actually reversed. This car has been in my family for many years and had been running for most of them so I was very skeptical of these wires being backwards. I did find a few other issues that I had to address but I am just glad it is now running. It starts everytime with just a quick tap of the starter.

The sad news is the waterpump seized. I will start a new thread regarding the water pump. I really just wanted to update everyone as well as thank everyone who offered such great advice and for being patient with me.

Thanks
Mike
 
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