Illustrator guide for 1984 pontiac trans am refers to 10499208 part as GM OEM Starter-Frame & Field.
Its the large cylinder that connects to starter sollenoid. Starter-Frame is the housing
Does anyone know if the starter field refers to coil field?

 

"FIeld" is the coils that are mounted in the "frame", that don't spin.

They're a piece of copper wire. They basically don't go bad.

Whatever you're trying to repair, chances are, messing with that won't do any good.

 

My mechanic told me coils are bad.
In hot start the starter will turn from very slow to none. Bad coils are like a large resistor which stops current to flow through starter motor,
I bought anothet starter ac delco rebuilt same all samo.They rebuild starters but do not change the coils.
I need a nre starter or rebuilt mine but not just service. I want to replace coils.

 

Heat soak is the result of coils swelling

 

The resistance of copper changes based on the heat it is currently at, once the temperature goes back down it returns to normal. If your frame and field is having issues it is most likely caused by shorted turns. This reduces the magnetic fields developed in the motor and thus their horse power ratings. The copper in your starter motor is simple wire with a thin outer coating of resin. Multiple turns are installed on laminated cores. Heat will destroy the outer resin coating over time as well as the insulation between laminations in the core. This is why we use heat shields to keep header heat away from the starter. GM starters are pretty cheap as whole units. Unless you have something really special like a mini High torque starter you are better just taking your old starter in and exchanging it for a completely new unit with some kind of warranty. Granted all that is assuming your issue truly is your starter and not the fact that your headers are heat soaking your starter, you have a bad connection from the battery, or just a weak battery.