Powered Parachute Flying Handbook

Chapter 4 — Powerplants

Fuel Systems

The fuel system is designed to provide an uninterrupted flow of clean fuel from the fuel tank to the engine. See Chapter 3 for more information on fuel tanks. The fuel must be available to the engine under all conditions of engine power, altitude, attitude, and during all approved flight maneuvers. [Figure 4-12]

Fuel Pumps

Powered parachutes have fuel pump systems. The main pump system is engine-driven and sometimes an electrically-driven auxiliary pump is provided for use in engine starting and in the event the engine pump fails. The auxiliary pump, also known as a boost pump, provides added reliability to the fuel system. The electrically-driven auxiliary pump is controlled by a switch in the cockpit.

A diaphragm pump is the primary pump in the fuel system for two-stroke engines. Air pulses in the crankcase actuate a diaphragm and provide fuel under pressure to the carburetor. Four-stroke engines have a mechanical pump driven directly off the engine.

Fuel Plunger Primer

The fuel plunger primer is used to draw fuel from the tanks to supply it directly into the cylinders prior to starting the engine. This is particularly helpful during cold weather when engines are hard to start because there is not enough heat available to vaporize the fuel in the carburetor. For some powered parachutes, it is the only way to deliver fuel to the engine when first starting. After the engine starts and is running, the fuel pump pushes fuel to the carburetors and begins normal fuel delivery. To avoid overpriming, read the priming instructions in your POH for your powered parachute.


A choke or fuel enrichening system is an alternate method to provide additional fuel to the engine for initial cold starting. Actuating the choke control allows more fuel to flow into the carburetor.

Fuel Bulb Primer

The fuel bulb primer is manually actuated by squeezing the bulb to draw fuel from the tanks. This charges the fuel lines and carburetor float bowls before starting the engine the first time on a given day. After the engine starts, the fuel pump is able to deliver the fuel to the fuel bowls.

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