Definition

1. Noun:
   • The housing that encloses and protects a crankshaft: In an internal combustion engine, the crankcase is the sturdy metal casing that contains the crankshaft and, in many designs, also contains the engine's oil sump.

Usage

• The primary function of the crankcase is to protect the crankshaft and connecting rods from debris and to contain the engine oil that lubricates these moving parts.
• It is a fundamental component of piston engines, located below the cylinders.

Examples

• Noun:
  • A leak in the crankcase can cause oil to drip onto the ground.
  • The mechanic removed the oil pan to access the bottom of the crankcase.
  • Modern engines often have a crankcase ventilation system to manage pressure.

Advanced Usage

• "Crankcase ventilation": A system that routes gases (blow-by) that escape past the piston rings from the crankcase back into the intake to be burned, reducing emissions and preventing pressure buildup.
  • A clogged PCV valve can disrupt proper crankcase ventilation.

Variants and Related Words

• Crankshaft (n): The main rotating shaft of an engine, which converts the reciprocating motion of the pistons into rotational motion. It is housed within the crankcase.
• Oil pan / Sump (n): The detachable lower part of the crankcase that holds the engine's lubricating oil.

Synonyms

• Engine block lower section (in some contexts, though technically the block and crankcase can be integrated or separate).
• Bedplate (a structural base that forms part of the crankcase in large engines).

Related Phrases

• "Crankcase oil": The lubricating oil contained within the crankcase.
  • It is important to change the crankcase oil regularly.
• "Crankcase explosion": A dangerous condition in large engines where flammable vapors in the crankcase ignite.
  • Proper maintenance helps prevent the risk of a crankcase explosion.

Noun

1. housing for a crankshaft