[meyousikmann]

Wow, heat shield for starter. Never would have thought of that. I am going to try it out. Thanks for all the replies.

["QUICK-SILVER"]

Originally Posted by meyousikmann

Wow, heat shield for starter. Never would have thought of that. I am going to try it out. Thanks for all the replies.

Most I've seen had a heat shield over the solenoid from the factory. It was suppose to help with hot 'no' start situations.
The hotter the windings in the solenoid and starter get, the less current flows through it. Just the nature of the beast when dealing with copper. Same thing holds true for battery cables.
Batteries also lose power when they get too hot. About the same as severe cold.

Always make sure cable connections are clean and tight, battery, starter, and block.

Hot engines are harder to turnover also, where cold engines usually spin easy. So don't rule out starter getting weak. Worn bushings and brushes make the starter weaker.

[2002Z4CSS]

Do a voltage drop on thew negative and positive cable when the engine is hot. May need a new cable due to high resistance.

[ve3wireless]

I had an eerily similar condition to yours here with my '78 T/A, back some 18 years ago, or so...

Finally I got underneath the car, & to my surprise, found that one of the wires hooked up to the starter was loose! In fact, LESS than finger-tight...

I simply cleaned everything up down there, applied new lock "star" washers on all the appropriate electrical connections, & that was the end of my issues...

I'll wager you have something similar there, i.e. just a bad connection. There's no heat shield on my car, & it starts just fine in our 90F Ontario Julys here now, hot or cold.

Eddy
Ontario, CANADA