new guy ignition problem

[tchevy]

Hey all,new guy here .I use another forum for popup campers called popup explorer.This is a great resource for campers as Im sure this is a great site for auto mobile owners.HAving said that I have a problem with my 92 chevy k1500. It is a z71,350,4x4 ,automatic with126000 mi. The problem seems to be in the ignition.When cold starts up first time every time, but once it reaches normal operating temps and is shut off sometimes it will not start again until 20-30min later.When i say it will not start I mean it will not do anything, wont even crank.I am not a mechanic buy any means but can find my way around an engine and not afraid to turn a wrench.The battery is new and the terminals are clean the starter was replaced last summer (no loose connection to starter).
Anybody ever ran in to this before or have any ideas? I hope I am doing this right, if I am not someone please tell me. Thanks in advance.
TCHEVY

[MagicRat]

The starter motor or cable to the starter is becoming heat-soaked, likely from the exhaust pipe heat.
Electrical resistance goes up when the electrical parts heat up.
Chevy small block v8's have been known for this problem since the late 1950's.

Often there is a small heat shield attached to the starter motor. If this was left off when the motor was replaced, the starter has no protection. There are some effective, larger than stck heat shields avaliable from speed shops and custom car stores.

You can also try wrapping the exhaust pipe near the starter in insulating 'header wrap' This is a heat proof fabric that comes in a 2 inch wide roll and does a great job of insulating heat.
Also your cable to the starter may be corroded or defective.