Older cars without fuel injection use mechanical fuel pumps that are bolted to the engine blocks. Their simple construction makes them reliable and inexpensive, but they can be misdiagnosed as bad if the fuel hose that brings gasoline from the tank to the pump is not intact. A deteriorated hose allows air in the line and the pump is unable to pump the fuel from the tank. Always make sure the supply hose is in good shape before testing a mechanical fuel pump.
Raise the hood of the car and remove the air cleaner. Use a wrench to remove the fuel line going into the carburetor. This line is often made of steel tubing, so be very careful not to bend or kink it when pulling it out of the carburetor.
Place a fuel hose over the end of the steel line and insert the other in into a plastic cup. Have an assistant crank the engine for 10 to 15 seconds. The cup should nearly fill, and as the engine spins, a forceful pulse of fuel spray in sync with each revolution. If a small, weak stream of fuel is all that ejects from the hose, replace the pump.
Reinstall the fuel line. Be careful and precisely align the steel line before fitting the line retainer back into the carburetor. It is easily crossed and will permanently damage the threads. Replace the air cleaner.
