Hard to re-Start once engine warmed?

[EL GRANDE HONCHO]

Hello:

I have a 1980 J10 AMC V8....

When I crank on a cold engine, it turns over fine (starter engages). However, after it runs to normal temp, and I shut off and try to restart, it does not want to turn over. Almost like a dead battery. Once the starter engages, it will fire and run fine.

Runs at 14.4V when first started on a cold engine (which is normal I know), and 12V when it eventually starts (which I also think is normal after running for awhile at 14.4V?), so I don't think this is a battery/alternator issue?

Starter solenoid problem? Starter?

any help much appreciated!

[AwesomeJ10]

perhaps the exhaust manifolds are heating up the starter which is causing the starter to not work well?

[Tatsadasayago]

Sure sounds like classic starter heat soak.
You can roll the dice and get a reman starter fairly resaonable and see what happens.

Now, if the warm engine turns over but 'lumps up', that is a different thing. That is usually caused by too much initial timing and/or fuel dripping into the manifold.

[EL GRANDE HONCHO]

Humm. I am running custom exhaust. Need to look to see how hot starter may be getting

[EL GRANDE HONCHO]

Sure sounds like classic starter heat soak.
You can roll the dice and get a reman starter fairly resaonable and see what happens.

Now, if the warm engine turns over but 'lumps up', that is a different thing. That is usually caused by too much initial timing and/or fuel dripping into the manifold.

No, it's not doing that. Starter not engaging at all when hot, then finally spins ever so slow

[Tatsadasayago]

Okay,
AMC used a Ford style starter for many years and I believe up until the mid 80s when Chrysler bought them. The Ford starters generally need 600+ DC Amperes of current before they will engage. If less than that, the solenoid will begin clicking or stuttering.
The failure chain in the starter system begins at the battery, then through a cable to the fenderwell mounted solenoid. From there the current flows down to the starter.
I would suggest you inspect/test your cables for corrosion first.
It's kinda tricky to do, but you can test the voltage at the starter with a volt meter while cranking cold and then hot. If the starter is drawing too much current when hot, the voltage will drop too much causing a slow crank or solenoid chatter.

With what you describe, I'd say your issue is a partial starter failure from heat soak and possibly bad power cables.
I had a similar issue last summer on my rig so I replaced both positive and negative cables and the slow cranking problem went away.