Scout car, White stalls
Here is what another Gent said... Applies to many vehicles:
Rob,
Next time you stallt-pull the high tension lead out of the distributor and hold it near a ground-a cylinder head bolt usually works well. Make sure all the paint and rust are cleaned off the bolt head. If there is no spark, the bolt may not be well grounded(rust on threads,etc.) so clean off something else and try the spark test again. Hold the lead about 1/16" away from the ground. An ignition in good shape can usually spark up to 1/4" gap.
Vapor lock occurs when gas in the fuel system(carb, fuel lines, and fuel pump) gets heat soaked-i.e. the engine is hot and gets shut off. There is no movement of fuel so it sits there cooking away. Eventually it gets so hot that it starts to boil and floods the engine. The problem is much worse these days because the gas has ethanol in it which has a much lower vapor pressure so it vaporizes at a lower temperature than gasoline. To clear a flooded engine, hold the gas pedal down at full throttle and crank the engine over. Eventually it will suck all the raw gas and gas vapor thru the engine and start. Don't pump the gas pedal because every time you pump the pedal the carb squirts a shot of gas into the engine.
It's been my experience that vapor lock rarely occurs when driving because the gas is cool going into the carb and passes right thru and thereby cools the carb. Air is also being blown by the carb and intake manifold by the fan and road wind which also keeps the intake system cool.
Usually it is an ignition problem. The condensor in the distributor can go bad gradually and it will short out when it gets hot. This keeps the ignition coil grounded so it can't produce a spark. The ignition coils can go bad also. There can be a break in the internal coil wiring but the wire ends are still touching, or the insulation between the coils can go bad. When the coil heats up, the wire expands and wire ends at the break quit touching or the insulation breaks down so the spark jumps from coil to coil with the end result of the coil not working. Let everything cool down and it starts to work again.
It might be easier to install new points, condensor, coil, and spark plug wires. Other than the coil, the other stuff is really cheap and it is basically just a tune-up which the truck probably needs anyway.
Hope this helps.
Dennis
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