noun
- Plural of blowby; the escape of combustion gases past the piston rings in an internal combustion engine into the crankcase.
Usage: technical; automotive
Examples
- Excessive blowbys can indicate worn piston rings that need replacement.
- The mechanic detected high levels of blowbys during the engine diagnostic test.
- Blowbys contribute to increased crankcase pressure and oil degradation.
- Modern engines are designed to minimize blowbys through improved ring sealing.
- The technician measured blowbys to assess the engine's overall condition.