87 with starter issues

[OftenWrongNeverUncertain]

Engine starts up just fine when cold. Let it warm up and shut it down, the starter is so slow it won't start the truck. Let it cool for 5 to 10 minutes and it starts up fine. No matter how long it runs for, after warming up the starter doesn't have the power to rotate the engine fast enough to start. It's like the battery is dead, but it's not.

The engine is not overheated or anything either. I don't know what my oil pressure is because the gage does not work.

Is this just a simple bad starter, or do I have other issues somewhere?

 

[RonD]

Yes, reads like a failing starter motor

It could be the Battery cables are heating up near engine ends limiting their ability to pass higher AMPs
Starter needs 50-70amps instantly to turn engine
So the slower cranking speed reads like a limited AMP issue

But its far more likely(more common) for a warm starter motor to need more AMPs than these cables can provide even when new, than an issue with older cables

 

[OftenWrongNeverUncertain]

So, what would you change first, cables or starter?

 

[Curious Hound]

So, what would you change first, cables or starter?

I would check to make sure cable connections (both positive and negative) are clean and tight. Otherwise, like RonD, I’m leaning toward starter failure.

 

[RonD]

+1 ^^^
Starter

And just a heads up, new starter motors can be bad "out of the box" so keep the receipt handy
No part makers test anything now-a-days, just build it, box it and send it
"We" are the quality control department, lol, they provide the warranty