| Tanks | Store fuel. Most singles have one per wing; some types add a header tank for fuel feed under negative g or as a minimum reserve |
| Fuel selector | Positions typically LEFT, RIGHT, BOTH, OFF. BOTH is common on high-wings (gravity feed from both tanks simultaneously); low-wings often have only L/R |
| Gascolator / strainer | Lowest point in the system. Collects water and sediment. Drain before every flight |
| Engine-driven fuel pump | Main pump on the engine accessory case — mechanical |
| Electric auxiliary / boost pump | Used for start, take-off, landing and as backup if the mechanical pump fails |
| Primer | Injects fuel directly into the intake manifold for cold starts |
| Fuel quantity gauges | Float-based; per CS-23.1337 must read "zero" when tank empty. Unreliable — always confirm by dipstick / visual check |
