Hi,
I was just reading this and want to reach out and let y'all know what my 1982 720 pickup is doing...
It was doing the exact same for most of the summer, really hard cracking, I rebuilt the carb( all nice and clean with me seals), it kept getting worse until now it won't start at all, doesn't even try there is no sound.
I replaced the battery cables, cleaned the battery terminals, took out the starter, ( found the starter solenoid wasn't doing is job) got new starter and starter solenoid ( cheaper together) installed it, still nothing...
I checked voltage all the way to the ignition.
Once I turned the key, the voltage dropped from 12 to 1.3 where the pins and the ignition cylinder come together.
I got a new ignition cylinder ( the truck drove for 3 times then did the same thing)
I'm not sure where to start now but reading this thread, I'll change the oil... Work out from there...
Any other hints? ( There is no sound or any lights at all) I'm open to suggestions. It it my daily driver, if I can get her to and running once again... Thank you all!!