Help with my '68 please
 

I'm have a problem with my suburban-
Sometimes when I turn the key, nothing happens. No click. The dash lights come on, the headlights will come on, the battery is charged. It'll start if push started and I was able to jump the solenoid and start it once also (when I didn't have someone to push start it). After I got home, I went to try and diagnose, but it starter by the key just fine.
1 - battery seems fine.
2 - key switch makes the dash light up so it's working to some degree.
3 - starter did spin when jumped and sometimes with the key.

Truck has a 350 with hei, manual trans, and has been quite reliable for the last 6 years-- not a new build..

Any thoughts? Thanks

Re: Help with my '68 please
 

If it is an automatic, I would check the neutral safety switch. Or could just be a bad starter solenoid.

Re: Help with my '68 please
 

It's a stick-- would the solenoid click though? As it is now it either works or it doesn't even click

Re: Help with my '68 please
 

I'd inspect all the wiring between your ignition switch and start solenoid first, then the ignition switch itself. It's possible jumping good hot current straight from the battery cable would overcome a lazy solenoid, but probably not worth replacing the solenoid and/or starter before you look into the components between it and the battery.

And no, the solenoid wouldn't click if it was an auto with a P/N safety switch problem - when the switch is engaged it does its job by cutting the flow of electricity to the solenoid.

Re: Help with my '68 please
 

Double check the easy stuff first. Battery cables and connections. Both positive and the ground leads to the block. It could be as simple as a loose battery post clamp or a broken ground strap. There are three wear components in the starting system (4 if you have an automatic) The ignition switch, the solenoid and the brushes in the starter. On our trucks the switch is the easiest to test as it is easy to remove and check with a meter. Or duck under the dash and test it installed. Test from the start terminal to ground with the test light or meter for the installed test for voltage. Or if you have removed the switch, test for continuity between the BAT terminal and the ST terminal while turning the key to the start position. If that checks out use your tester of choice to see if you have voltage to the solenoid when you turn the switch. If you have voltage and it doesn't turn the starter then it is a toss up between the solenoid or the starter. At this point its going to be time to remove the starter. I would end up tearing the solenoid and starter apart as I would just have to know where the problem was. But most folks would just replace the whole unit. As your checking things out be on the look out for melted components like the ignition switch plug I removed from my Burban. With all these tests repeat them ten or so times each since you're searching for an intermittent problem.
Good Luck.

Re: Help with my '68 please
 

All the ghosts I've had like that have been loose connections...GROUNDS and positive.