Ran fine until..... need some help. (2 Viewers)

[45Dougal]

Today's adventure.

Checked battery, over 12 volts, close to 13.
Disconnected power at dist. and had 12+ volts.
Cranked engine while power was disconnected, dropped between 8 and 9.
Took apart cap and check the ohms on coil, all good.
Ran wire straight from dist. to battery, cranked as usual, but didn't start.
Pulled and check cylinder 1, 3, and 5, no spark.

Borrowing a dist hopefully tomorrow and see if that resolves the issue.

I chased wires today, lots of s*** not connected to anything.

Is this fuse box on the engine side of the firewall typical? If so, what is it running?

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The voltage at the feed to your distributor dropped from nearly 13V to 8V while cranking (with the distributor disconnected)?

That is a big drop in my book and the battery could be the cause. Have you tried switching the battery?
You could just try jumping it from another truck to give you a boost.
Alternatively you could try jumping ground to ground, and then use the second battery only to feed the distributor ( while the main battery cranks the motor).
This way you are sure that you have 12v to the ignition.

Has something changed with the alternator when you fixed the AC? Maybe killed the battery somehow or just coincidence.

Start by checking your battery terminals

 

[69FJ40NJ]

So checked the coil, and the readings were good. Buddy brought over another GM hei dist and we switched out the coil, installed and it fired right up like nothing happen.

Adjusted the timing and took it for a few spins around the block, all good. We will see if it starts tomorrow.