83 XJS with a Chevy 350 BUT this starting issue occurred with the old engine as well.

Brand new powermaster xs starter. Battery is brand new. Replaced the starter relay with a modern one a couple years ago. Both main posts in the engine bay have recently been cleaned thoroughly. Two very solid ground connections between the engine and the body.

Car starts up quickly when cold or slightly warm. But when I have run the car for 10+ minutes and turn it off, the next time I try to start it, it acts like the starter gear turns, then stops for a second, then turns, etc a couple more times and then it finally starts. I don’t know how else to describe it. It’s very much a start-stop-start-stop sort of cadence with the starter but only when the engine is up to temp.

I doubt it’s the engine since it’s brand new and the old one did this as well.

I would assume something ignition related but I don’t know what ignition component or relay would be affected by engine temp. It NEVER does this when the engine is cold, starts up no problem.

 

Check the heavy cable that runs from the firewall "+" post to the starter.

Corroded? High resistance?

Cheers
DD

 

I’m fairly certain it is in good shape but I’ll double check. Thanks for the suggestion

 

What can happen is the cable develops corrosion inside the insulation, hidden from immediate view. Measuring the resistance is the best bet. But sometimes peeling back a bit of the insulation will tell you what you need to know

Cheers
DD

 

Ah that’s a good thought, thanks for explanation Doug.