My 70 won't start

[Dads 70 long bed]

My 70 C10 wont start.
new plugs, cap, rotor, wires, coil, points and condenser.
I put her in the garage to rebuild the carburetor.
Now, no spark. the points are at .030, the positive side of the coil reads 5.7 vdc
the negative side is zero. The run terminal on the starter solenoid reads 5.8 vdc I use the black side of my jumper cables to reference ground and clamp it to a spark plug to look for spark. I can lay the plug on the cowl to watch for spark, since I have no help.
Any ideas?

[HO455]

Just for clarification, the truck ran with the new plugs, wires, and points when you drove it into the garage? Then you removed the carburetor, rebuilt it, reinstalled it and now you have no spark?

And Welcome Aboard. We would all love to see pictures of your truck.

[Dads 70 long bed]

While I had the carburetor off, I reworked the ignition system. And now it won't start.

[Corts60]

That voltage is way too low. What is your battery voltage at the terminals? Sounds like you have a dead battery.

[Dads 70 long bed]

The voltage at the battery is 12.28
It cranks very nice.
No struggle at all.
But I have zero spark, not even a weak one. I'm sort of thinking it has something to do with my ignition switch. I'm still looking for a pin out on the switch so I can check it

[tdangle]

That voltage may be correct if the points are closed. Take the dist cap off and make sure you have a gap of about .019 when the heal of the points are on the high ridge of the rotor assembly. that should get you real close. also make sure you didn't short the points to ground with the condenser. If you watch the points while cranking they should open and then close. .030 is too big.

[HO455]

What is the battery voltage when the starter is cranking?
How did you measure the voltage at the coil?

[tdangle]

Odds are if it worked when you drove it in and now doesn't then it was something you did. double check all your work. Does not sound like a bad battery if it cranks OK. You should have a positive voltage to the + of the coil, and the points supply the neg or ground. When the points are closed current runs thru the coil, which probably is why you only see about 6v or so at the positive terminal. There is a resistance wire running the voltage to the coil as a full 12V will kill points real quick. When the points open the field inside the coil collapses and causes the spark. Disconnect the wire from the neg to the points and you will probably see a full 12 volts at the pos terminal.

[Steeveedee]

You should have 30º dwell, not a .030" point gap. The points may not be closing...or opening. Probably not opening, given the voltage. Also verify that the power wire from the coil to the points is attached properly. That voltage is OK for running the engine. BTW, a battery at 12.28V is pretty low on charge. It's probably low due to the cranking you've been doing. During cranking, power comes from the solenoid "R" terminal up the yellow wire attached to the coil + terminal, as the "Start" position of the ignition switch does not feed power during cranking.

[Dads 70 long bed]

Thanks for all the help.
I changed the points and she started.
Not sure what was wrong with them, but the new ones are in it now.
Thanks a again.
I'll give her a bath and show you guys some pictures

[HO455]

Good work! And thanks for posting your success.