Fuel System and Nozzles Flashcards
What can add or subtract 100 PSI inside the Heavy-Duty Nozzle
Addition or Subtraction of the Shim by .002
Return Fuel- Opening Pressure Adjustment- Valve Lift Adjustment- Opening Pressure Spring- Locating Clamp- Fuel Inlet- Edge Filter- Nozzle Body- Nozzle Valve- Teflon Sealing Ring- Spray Tip.
Pencil Nozzle
Injection nozzles perform three functions:
1.Disperse fuel spray to mix fuel with air 2. Atomize fuel for efficient combustion 3. Complete nozzle shutoff to prevent fuel leakage
What type of brush do you use to clean nozzles?
Brass wire brush
Nozzle Test:
- Spray Pattern and Chatter 2. Opening Pressure 3. Valve leakage
Prime job of the diesel fuel system?
To inject a precise amount of atomized and pressurized fuel into each cylinder at the proper time
Major parts of the fuel system:
- Fuel Tank 2. Fuel Transfer Pump 3. Fuel Filters 4. Injection Pump 5. Injection Nozzles
The injection system must?
- Supply the correct quantity fuel 2. Time the delivery of the fuel 3. Control the fuel delivery rate
The fuel injection system must? (Continued)
- Break up or atomize the fuel 5. Distribute fuel evenly through the cylinder
Elements of fuel tanks?
Capacity 2. Size 3. Shape 4. Venting 5. Openings
Typical problems of the fuel tanks?
Leaks, condensation, dirt
Methods to locate a leak on tanks?
Wet method
Air pressure method
Two types of electric fuel gauges?
Balancing coil gauge
Thermostatic gauge
Types of diesel fuel lines?
Heavy-Weight
Medium-Weight
Light-Weight
Fuel filtration is critical because?
- Diesel fuel lines tends to contain particles and moisture 2. Injection parts are precision-fitted
Stages of a filtration system?
Filter Screen
Primary Filter
Secondary Filter
Three ways fuel filtration can be done?
Straining
Absorption
Separation
Dual filters function in?
Series
Parallel
Types of injection systems?
- Early common rail 2. Accumulator 3. Injection Pump 4. Electronic Unit Injector 5. Electronic Injector/ High Pressure Common Rail
Types of injection pumps?
In-line
Distribution
Most common fuel injection pumps
Individual pump and nozzle for each cylinder
Pumps in common housing, nozzles for each cylinder (in-line
Most common fuel injection pumps (continued)
Single pump serving injection nozzles for several cylinders (distributor)
Important qualities of gasoline?
- Proper Octane rating 2. Easy Starting 3. High oxidation stability and freedom from gum
Important gas qualities (continued)
- Freedom from foreign matter, (water and dirt) 5. Use of fuel additives 6. Volatility
Why are additives used?
To raise octane number and to combat gum formation and surface ignition
Factors affecting knock
Antiknock quality of gas
Octane number requirement of the engine
What is bad for your engine?
Alcohol
What do you add to your engine?
Dyes
Antioxidants
Carburetor detergents
Antiknock additives
Diesel major grades
1
2
4
Sulfur
15 parts per million is Ultra low sulfur fuel
What is pour point?
Lowest temperature which fuel ceases to flow
What is cloud point/ gel point?
Temperature in which diesel becomes cloudy and forms wax crystals
When does the injection pump perform most efficiently?
When the fuel has the proper “body” or viscosity
What is flash point?
Temperature to which fuel must be heated to create a mixture of fuel vapor and air
What is Carbon residue?
The amount of material left after evaporation of the fuel
What is ash?
Small amounts of non burnable material
What factors should you consider in storing of fuels?
Protection and fuel quality
Safety
Convenience
Cost
What conditions you must control for a satisfactory quality of your gasoline?
Control loss through evaporation
Avoid gum deposits
Protect from water and dirt
Types of close nozzles
Inward
Outward
