HAND FUEL PUMP
   

the hand fuel pump is located under the front seat floorboard and just in front of the seat

The fuel, oil, and water pumps on later model Stanley steamers are run from the rear axle of the car. Whenever the car is in motion the pumps are in operation. However, when a Stanley needs to be steamed up the burner must be operated but the car canít be in motion. This would result in depletion of the small quantity of fuel in the fuel pressure tanks in a short matter of time.

The hand fuel pump provides a way to pump fuel from the main fuel tank to the fuel pressure tanks and maintain main fuel system pressure during the firing-up of a Stanley when the burner is firing. The hand fuel pump is located under the front floorboards and the fuel pumpís piston is on a common shaft with the hand water pumpís piston. A pump handle connected to the shaft between the pump pistons rises from the floorboards and is rocked back and forth so that both the hand fuel and water pumps operate.

 

OPERATION OF THE HAND FUEL PUMP

The hand fuel pump is a simple construction of a piston within a cast bronze cylinder housing. There are no check valves incorporated in the hand fuel pumpís housing. Operation of the hand fuel pump relies on two check valves installed at strategic locations within the fuel system plumbing. A check valve in the fuel supply line near the fuel tank (fuel supply check valve), and a second check valve after the fuel pump (power fuel pump check valve), provides the necessary valve action for proper operation of the hand fuel pump.

When the pump handle is moved such that the hand fuel pumpís piston is pulled out of the hand fuel pumpís cylinder, fuel is sucked out of the fuel supply tank at the rear of the car and into the space once occupied by the piston. The power fuel pumpís internal check valves along with the check valve that is located past the power fuel pump insure that fuel is not sucked out of the fuel pressure tanks and back into the hand fuel pumpís cylinder as the piston is moved.

When the pump handle is moved such that the hand fuel pumpís piston is pushed back into the hand fuel pumpís cylinder (i.e. the pump handle is pulled towards the front passenger seat), the fuel in the cylinder and piping connected to the hand fuel pumpís cylinder is pressurized. The check valve just after the fuel tank now closes and stops the fuel from flowing back into the supply tank. However, as the hand fuel pumpís piston continues to be moved into the hand fuel pumpís cylinder, pressure builds in the piping between the fuel supply check valve and the power fuel pump check valve. When the fuel pressure within the piping becomes greater than the pressure of the fuel in the burner fuel pressure tanks, the power fuel pump check valve opens and allows the fuel to flow into the burner fuel pressure tanks. At the end of the stroke the check valve just past the power fuel pump closes to maintain the fuel at the pressure it is at within the burner fuel pressure tanks.

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