1966 not starting - ideas?

[Dan1970]

Hi all, I am new to the forums and have a 1966 C10 that was originally a manual transmission truck, now has 3-speed floor shift automatic. Recently I was coasting at idle when there was a loud POP noise, and the engine immediately stalled. It was strange, but nothing externally looked out of place, so I cranked it right back up and drove home. About a week later, I cranked it, and while still in Park, the same POP sound and engine stalled.

Fast forward a couple of weeks. Went to start the truck, and the battery (brand new) was dead. Jumped it off from my car, but the engine would only turn about 1/8 turn (but made a single loud click). Banged on the starter, no luck. Replaced the starter, no luck. Tried different positions with (what I think is) the Neutral Safety Switch, no luck. The starter has a good ground, and the S terminal has 12v.

The drained battery leads me to believe the problem is electrical, but could this be a mechanical issue related to the loud POP? Thanks in advance for any advice.

[TopFuel1966]

You didn't say which motor you have but before you replace any more external parts make sure it isn't seized up by turning it over a couple of revs by hand.

[TJ's Chevy]

Turn it over by hand to verify it isn't seized.

Replace the battery as it's probably toast.

Loud pop? And then dies? Sounds possibly fuel related as well. Sounds like a backfire out the carb which could be the float level is not set right or the engine is running to Lean.

If it's ignition you can check the OHM's on the coil to verify it's ok. Then check the points if you have those(not HEI) and be sure they are not burned up. Faulty condensers don't help either.

If it will barely crank and the starter makes a loud clicking noise that usually means the battery is toast, to verify you can simply change batteries, or hook your to a jumper cable and jump start it. If it jump starts the battery is shot.

[andyh1956]

If you have a v-8 w/ the old nylon coated cam gear it could have jumped a tooth or so & got outta time & that could be the pop you heard. Start by verifying #1 cyl TDCC then check to see which wire your rotor is pointing at.

[old cruiser]

loose distributor clamp bolt ?, as above tdc no 1 cyl check rotor position

[Lugnutz65]

Do you have an HEI distributor? If your alternator isn't charging the battery properly, then you would eventually drain the battery because the HEI would be drawing 12V straight from the battery. If what I just said is true, then the first time it "popped" and quit running, and then started back up again for the drive home doesn't quite fit the situation I described. Just some food for thought. But it does sound like an electrical problem rather than mechanical. Perhaps a short in one of the wires going to or from the coil (or HEI)?

[andyh1956]

If you do have an HEI the rotor buttons on those are notorious for failing also, but when they fail they are usually toast & won't start again.

[Dan1970]

Sorry guys, finally got around back around to this today. Thanks all for the suggestions.

Someone asked what motor this is. It's a 1970s Chevy 305.

I can turn the motor by hand, so it is not seized. I left the starter connected and on the bracket, but took off the belt. Same loud "click" and the starter did not turn at all. This makes me think it's an electrical problem, maybe neutral safety switch? Any suggestions what to look for next?

[68gmsee]

If you hear a click, that means the starter solenoid is being actuated. So, if you have the required voltage to turn the engine and it's a new starter it should turn over. Be aware that you may have the correct voltage but not the required amperage.

Try another good known battery. Double check the battery cables and starter wiring connections -especially at the battery terminal. I have seen the cables corrode internally and it's not visible unless you peel the insulation back.

If you do get it started check the battery voltage while running. A meter set at 12vdc across the pos and neg terminal should read app 14.5 plus or minus .5vdc.