Solutions It operates the valves of an internal-combustion engine has 7 entries with similar clues
- sumpsCasings holding oil in internal combustion engine
- xenonGas used in thermionic valves
- motorInternal combustion engine
- petrolFuel for the internal combustion engine
- big-endImportant part of the connecting rod in an internal combustion engine
- air-filterCar's feature that keeps particles out of an internal combustion engine
- spark-plugElectrical device in an internal combustion engine