''I'm going to fix it up someday'' The resurrection of a '74 Dart Sport......
Hi Tom, Did the carb spacer solve your problem?
What are the symptoms of "heat soak"?
I'm glad to see you are still doing some tinkering with the Dart.
Love this thread!
Thanks for the compliment and the question!
There's still a lot more ''tinkering'' left to do.
Well, the phenolic spacer (which is a fancy word for plastic/fiber reinforced) did help a lot, but it didn't solve the problem completely. It did make a big difference though.
The float level is correct and the idle is low enough. The engine doesn't ''run on'' when shut off, and the temperature remains at 180 all of the time no matter how hot it is out. The car does not ''vapor lock''.
The symptoms of heat soak are as follows:
You start the car and drive it for awhile getting it up to full operating temperature.
Shut the car off and leave it for 10 minutes or so.
You go to start the car, only to discover it is flooded and you have to put your foot to the floor and crank it until it starts.
You can also smell raw gas.
If you shut the car off and take off the air cleaner lid, you can actually see gas bubbling (boiling) out of the bowl vent and going into the intake manifold, flooding the car in effect.
So what the phenolic spacer does is provide a barrier between the hot intake manifold and the carb so when the engine is shut off, the heat doesn't ''soak'' the carb and the gas doesn't boil out and flood the engine.
The thicker the spacer in theory, the better the result.
I actually wanted to install a 1'' spacer but i decided to use the 1/2'' one because of hood clearance between the air cleaner lid and the bracing.
As it is, the lid JUST touches the bracing in 2 points lightly enough to cause a scuff mark on it.
I will probably modify the bracing some time in the future, but for now, it's not a big deal to me.
I might end up trying a different brand of spacer or even a Thermoquad carb in the future and see what that does.
I am keeping the original air cleaner regardless.
Another thing to consider is the gas these days is a lot different than the old days and may cause the problem of ''heat soak'' to be worse.
Thanks again,
Tom.
