Engineering Flashcards
What is a seacock?
water inlet for the water pump
Purpose of oil sump
collect and cool oil collect collect and cool oil
Crankcase
House for the crankshaft
Cooling circuit
Green Square - Water, Red Circle - Oil
Signs of burnt head gasket
Running engine to hot, Oil stains, bubbling cooling water tank, EMULSION (higher reading on dipstick due to water in oil sump)
Torque Wrench
Tighten screws/nuts with equal force ACCORDING TO SPECIFICATION OF THE ENGINE
Blue Smoke
Oil entering compression chamber
White Smoke
Water entering compression chamber
List Items connected to Cam Shaft
1.
2.
3.
4.
5.
- Cam Shaft
- Cam
- Push rod
- Valve Spring - (USED TO CLOSE THE VALVE)
- Rocker Arm
Timing Gears & chain?
Ratio Crankshaft : Camshaft in a 4 stroke engine
Used to transfer rotation of crankshaft to camshaft which moves push rods and rocker arms to OPEN the valves
SPRING - Closes the valves
2:1
Where is the Tappet valve (Cam follower) located
Between the cam and the push rod
What does rocker arm do?
What does valve spring do?
Rocker Arm - Opens the Valve
Spring - Closes the valve
Valve clearance
Located between rocker arm and valve STEM which ensures VALVE CLOSES FULLY AFTER ENGINE WARMS UP
0.025 inches in the normal clearance OR REFER TO ENGINE MANUAL
Which valve normally has a larger diameter
INTAKE
What happens if the valve clearance is to small after the engine warms up?
Valve wont close properly leading to engine COMPRESSION LOSS
Engine wont run smoothly
What happens if the valve clearance is to BIG after the engine warms up?
Valve become NOISY - TAPPING SOUND
Engine wont run smoothly
What does Feeler gauge tool do?
Hand tool for adjusting valve clearance
Gudgeon Pin?
Connects piston to the con rod
Big end bearing?
Small end bearing?
Con rods join the crankshaft
Gugdgeon pin joins the con rod
Main Bearing?
Symtoms of warn out bearing?
Supports crankshaft on the engine block
knocking noise and low engine oil pressure in a running engine
Engine speed?
Number of rotations equivalent to the rotation of the crankshaft
Flywheel
Stores engery during expansion and releases it during the other 3 three strokes to make the engine run SMOOTHLY
Stroke
Distance travelled between TDC and BDC
1 stroke - Camshaft turns 180 degrees (4 stroke engine 720 degrees)
2:1 ratio
Power stroke Piston movement
CLOSE TO TDC, spark which ignites fue/air