BEST EXPO RUNZ ASSISTANCE WEBSITE. NO.1 BEST DELIVERY OF EXAM RUNZ
100% GUARANTEE OF GETTING ANSWERS MIDNIGHT..IT’S OUR CULTURE, NO DOUBT
===================================
SECTION A: ANSWER ALL QUESTIONS
(1)
Phasing refers to the process of ensuring that the fuel injection timing is synchronized with the engine’s crankshaft rotation.
Calibration, on the other hand, refers to the process of adjusting the injector pump’s fuel delivery rate to match the engine’s requirements.
===================================
(2a)
The delivery valve ensures that fuel is delivered under pressure into the fuel injector nozzle and maintains the required pressure.
(2b)
The delivery valve is located in the injector pump, in close proximity to the injector nozzle.
===================================
(3a)
Detonation is a phenomenon that occurs when a portion of the fuel-air mixture in an internal combustion engine ignites prematurely, before the spark plug fires. This premature ignition causes a rapid increase in pressure, resulting in a knocking or pinging sound.
(3b)
A hot spot is an area within an internal combustion engine’s combustion chamber where the temperature is significantly higher than in other areas.
===================================
(4a)
Splines provide a secure and flexible connection between the shaft and other components, such as the propeller or gearbox, allowing for smooth power transmission and accommodating any misalignment or vibration.
(4b)
(i) Tubular shafts are lighter, which reduces the weight and the overall strain on the engine.
(ii) They are stronger due to the structural properties of their hollow shape, offering better resistance to bending and torsional stresses.
===================================
(5)
(i) Tyres
(ii) Brakes
(iii) Engine oil level
(iv) Lights
===================================
(6a)
Universal joints allow for the transmission of rotary motion between components that are not aligned in a straight line, accommodating changes in angles between the drivetrain parts.
(6b)
The propeller shaft is subjected to torsional stress due to the twisting motion caused by the engine’s rotational force, and compressive stress as the shaft transmits force through its length, causing it to bend or compress.
===================================
(7a)
(7b)
Pintal nozzle
Used in early indirect injection (IDI) diesel and most gasoline engines, this nozzle has an inverted conical tip that produces a conical spray pattern. The throttling pintle nozzle is commonly used in indirect-injected engines.
===================================
(8a)
(i) A dial indicator
(ii) A micrometer or vernier caliper
(8b)
The propeller shaft is mounted on a set of bearings, and the dial gauge measures deviations in the shaft’s alignment. Any variation in reading indicates a bend or misalignment.
===================================
(9a)
(i) Wet liner
(ii) Dry liner
(9b)
The sealing ring prevents leakage of coolant, oil, or gases between the liner and the engine block, ensuring efficient operation and preventing contamination.
===================================
(10a)
Sludge forms from the breakdown of oil due to heat, contaminants, or poor-quality oil, leading to the accumulation of carbon, dirt, and other debris in the engine.
(10b)
Vapor lock is a condition where fuel vaporizes in the fuel lines or pump, disrupting fuel flow to the engine, often caused by high temperatures or low fuel pressure.
===================================
SECTION B: ANSWER FIVE(5) QUESTIONS ONLY
(12a)
The function of the accelerator pump is to provide a temporary increase in fuel flow to the engine when the accelerator pedal is suddenly pressed. This helps to prevent a hesitation or stumble in the engine’s response, allowing for smoother acceleration.
(12b)
The acceleration fuel spot refers to the brief, additional amount of fuel injected into the engine’s cylinders during sudden acceleration. This extra fuel helps to enrich the air-fuel mixture, compensating for the increased airflow and ensuring a smooth, responsive engine performance.
===================================
(13a)
(13b)
(i) Plunger
(ii) Barrel
(iii) Roller
(iv) Delivery valve
(13c)
(i) To regulate the fuel pressure and flow rate to the injectors.
(ii) To prevent fuel from flowing back into the pumping element after injection, ensuring a consistent and accurate fuel supply.
===================================
(15a)
(i) Reduced steering effort: Power-assisted steering reduces the physical effort required to steer the vehicle, making it easier to maneuver.
(ii) Improved steering response: Power-assisted steering provides a faster and more precise steering response, enhancing the overall driving experience.
(iii) Increased safety: Power-assisted steering can help prevent accidents by providing more control over the vehicle, especially during emergency maneuvers.
(iv) Reduced driver fatigue: By reducing the physical effort required to steer, power-assisted steering can help reduce driver fatigue on long trips.
(15b)
(i) Power Steering Pump
(ii) Control Valve
(iii) Power Steering Gear
(15c)
Failed safe refers to the design of the power-assisted steering system, which ensures that if the system fails or loses power, the vehicle’s steering will default to a manual mode. This means that the driver will still be able to steer the vehicle, albeit with increased effort, ensuring the vehicle can be safely brought to a stop.
===================================
(17a)
(i) Condensation: Temperature changes cause moisture in the air inside the petrol tank to condense, leading to water droplets.
(ii) Fuel Contamination: Petrol often contains small amounts of water due to contamination during storage or transportation.
(iii) Hygroscopic Properties: Some ethanol-blended fuels can absorb water from the atmosphere, contributing to water accumulation.
(17b)
(i) Combustion by-product: When a new engine operates, it burns fuel and produces exhaust gases. One of the by-products of combustion is water vapor, which can condense in the cooler parts of the exhaust system, leading to water droplets.
(ii) Unburned Fuel: During the break-in period of a new engine, it may not burn fuel as efficiently as after it’s fully broken in. This can lead to more water vapor being produced in the exhaust, which may condense and form droplets.
(17c)
(i) Gearbox: The gearbox is used to adjust the engine’s output to the wheels, providing different torque and speed levels. It allows the driver to control the vehicle’s speed and power for optimal performance and efficiency.
(ii) Overdrive Gear: The overdrive gear is used to reduce the engine’s RPM (revolutions per minute) during cruising at high speeds, improving fuel efficiency and reducing engine wear. It allows the vehicle to maintain speed with lower engine stress.
===================================
COMPLETED….We Remain Your Favourite Site.
Ensure You Subscribe For Your Next Paper
===================================
Leave a Reply