Holding idle

Last night after a 10 Mile run on the freeway, my engine decided not to hold an idle when stopping. This is the second time this has happened after a freeway run.If I shut it off and wait a few minutes on the street, it's back to normal and idles in neutral at around 1000rpm. Any suggestions???

Too hot? Vapor lock? (Fuel in pump, fuel line, or carbs boiling...)

Worse would be REALLY too hot and engine trying to seize.

If not running too hot as George mentioned, then I would first go with the fuel filter becoming clogged with dirt under driving conditions . Then after you let the engine sit a bit, the dirt in the fuel filtr "relaxes" enough until you are out on the road again and the same thing happens again.... Alan M

I agree, we usually see the fuel line, filter usually are found too close to the engine. If you look closely you can see when the engine is hot bubbles in the filter. That can cause a problem.

Look to see if you can move the fuel line far enough away from too much heat.