76 340 duster overheating at idle

Matthew Sermini said

Any idea on the causes or solutions? A couple months back I drove to the store, stopped and got gas, drove a minute down the road and hit a stop light. Took off then the engine died and took a couple minutes to start back up. I figured it was from the cold gas going into the hot engine. I have an edelbrock avs carb

Click to expand...

The problem is unlikely cold fuel going into a hot engine. I have proved that to myself by using a cool can. Unfortunately, using a cool can as a necessity in every day driving is way too much of a hassle.

Resolving a heat soak problem will involve keeping as much heat AWAY from the carb (and away from fuel going INTO the carb) as possible. Ceramic coated headers as an example. Running fuel lines as far away from heat as possible. Running a fuel return line regulator (like an injected system). Shielding the carb from heat (heat shields, phenolic/bakelite/wood spacers). Blocking manifold heat.

The #1 problem with fuel boiling in the carb is simply the fuel we have available to use. It's mostly garbage. Vapor pressures are high so the fuel ignites easier. That's fine when it's -20º. When it's 115º? ...not so good.

As an overall rule of thumb, DO try to NOT run a winter blended fuel on a warm/hot day. Of course...you don't know if you are pumping a winter blend or not. You can talk to your local distributor. They know...and will usually tell you when the switches (from winter to summer/from summer to winter) happen.

If you live in a warm climate, such blend changes may not take place.