Classic/Antique Car Repair: hot 65 impala, impala super sport, clutch fan

Question
I have a 1965 impala super sport with out air. All original as far as I can tell. When the car is hot and has sat for about 45 min. it will not start. ( motor does spin)I removed thermostat the car is running a little bit cooler.I wrap all fuel line with header tape to keep heat away. A friend told me the car needs a shroud, It's a 5 blade clutch fan about 2" from the radiator and I see no place to bolt on a shroud.

Help,  

Tom

Answer
If the motor spins but does not fire there could be three problems. First you have a problem in the ignition system that is effected by heat and causing no spark. Secondly it could be vapor lock causing the fuel to boil and turn to steam rather than a liquid that can be processed by the carburetor. And last it could be heat washing the oil down of the cylinder walls reducing compression. You are going to have to run some diagnostics when the engine is hot and won't start. Check for the presence of spark. Pull the coil wire out of the center of the distributor cap and hold the end of the wire about a 1/4 inch from a good metal surface. Preferably with a pair of insulated pliers. Then have some one crank the engine over. You should have a good strong blue spark. Next take off the air filter and with the key off and the engine not running, look down into the throat of the carburetor. Pump the gas pedal or linkage and watch for a couple of streams of fuel from the accelerator nozzles. No fuel, vapor lock or low fuel pump pressure. If you have spark and fuel and the engine does not run, the problem sounds like compression. A compression test is in order. Good Luck.
Brad