Engine Lubrication System
Purpose of Lubrication System
- Reduces friction and removes heat.
- Delivers lubricant to all friction parts.
- Vital parts are fed under pressure.
- Other parts rely on gravity and splash feeds.
Lubricating Cycle Overview
Initial Setup
- Motor Oil: Filled into the engine.
- Oil Sump: Drains oil via timing drive cavity and dedicated channels.
- Houses dipstick and oil pickup with strainer.
Activation
- Start Engine: Activates oil pump, drawing in oil and creating pressure.
- Oil Pump: Can be chain-driven from crankshaft, gear driven, or directly mounted.
- Pressure Relief Valve: Controls pressure limits, opens when pressure is too high.
Oil Pump Functionality
- Gear pumps (internal/external gear meshing) and gerotor pumps are common types.
- Variable Discharge Oil Pump: Another type of pump.
Oil Journey
- Oil Filter: Cleans metal dust and impurities.
- Bypass Valve: Allows oil to pass without filter if clogged.
- Oil Pressure Sensor: Located at the outlet.
- Cylinder's Block Oil Gallery: Directs oil to crankshaft's main journals.
- Lubricates main journals and bearings under pressure.
Crankshaft and Connecting Rods
- Crankshaft Channels: Direct oil to rod journals and bearings.
- Oil Mist: Created by sprayed oil, lubricates cylinder walls and pistons.
- Oil Sump: Oil returns here, cycle repeats.
Additional Components
- Cylinder Block and Head Oil Gallery: Lubricates camshaft and timing drive.
- Gravity and splash feed lubrication.
System Indicators
- Oil Pressure Sensor: Essential for monitoring system pressure.
- Placed downstream of the filter, and/or at the end of the oil gallery.
- Multiple sensors possible (upstream and downstream).
- Warning Light: Alerts low oil pressure.
Advanced Features
- Complex systems may include:
- Oil temperature sensors.
- Oil level sensors.
- Air or water-cooled radiators.
- Improved Lubrication: Additional oil passages, holes in connecting rods, oil jet nozzles.
- Lubrication for optional systems like turbochargers.
- Hydraulic lash adjusters and timing drives tensioner depend on lubricated systems.
Maintenance
- Oil Control Rings and Valve Stem Seals: Prevent excess oil in combustion chamber.
- Gaskets and Seals: Prevent oil leakage between stationary and moving parts.
- Regular Oil Changes: Necessary to prevent contamination and engine wear.
Summary: Regular maintenance and understanding of the lubrication system are crucial for engine longevity and efficiency. Subscribe for more educational videos on engine systems.