What you Should Know About Using Natural Gas Vehicles
Will I Receive the Same Fuel Mileage and Vehicle Performance?
Against popular opinions, methane carries more British Thermal Units (BTUs) than gasoline. The energy content of gasoline is dependent on the season and oxygenated fuel additives like methyl tertiary-butyl ether (MBTE) [used to increase the oxygen levels] that reduce emissions.
BTU levels for gasoline
- 114,500 for a summer gallon of gasoline w/ no additives
- 112,500 for a winter gallon of gasoline w/ no additives
- 112,000 for summer blends with MTBE
- 110,210 for summer blends with ethanol
- 112,210 for winter blends with ethanol
BTU levels for natural gas
- 114,000 year round
BTU levels for diesel
The clear winner and most expensive is diesel with 129,500 BTUs. Because fueling stations don’t have to advertise that they are using a 10% ethanol mix in their gasoline, most don’t; however, most stations dispense this mix.
What is the Difference Between Dedicated and Converted Vehicles?
- Runs on 100% natural gas
- Dependent on CNG fueling stations
- Can not turn off the fuel if it is overheating
- Expensive engine re-configurations to deal with 0 lubricants and high heat levels
- High maintenance costs
- Reduced torque and HP
- Reduced mileage
- High conversion costs
- Runs on gasoline or natural gas
- Runs on diesel + natural gas mixture
- Doubles the driving range
- Switch fuels while driving at the flip of a switch
- Starts on gasoline or diesel to lubricate the engine then switches to natural gas
- Low maintenance costs
- Increased torque and HP
- Increased mileage
- Low conversion costs
What is the Difference Between Aspirated and Direct Injection CNG Kits?
- Aspirated: These systems are first generation simple technology. Aspirated kits usually cost less since and are relatively simple and easy to install. They have a closed loop controller that receives feedback from an oxygen sensor to keep the vehicle operating optimally. The performance of these systems is limited because the air intake must be throttled down for them to work properly. Also, aspirated CNG kits tend to trigger the “Check Engine” light which is a common occurrence. This application is intended for older vehicles with a carburetor.
- Direct Injection. These systems are the leaders in CNG Conversion Kit technology. They utilize a powerful microprocessor which supports the built-in automatic correction and calibration system. Because these systems are designed using advanced electronics and deliver far superior performance they will cost more than aspirated kits. They have evolved significantly in recent years. The latest technology in these systems utilizes extensive electronic sensors, injectors, and a 32 bit computer that integrates with the vehicle’s computer. This provides the best fuel economy and performance. A “Check Engine” light is not acceptable with these installations.
Are There Special Maintenance Needs for CNG Converted Vehicles?
Natural gas engines work essentially the same way as gasoline engines. An air-fuel mixture is injected into the intake manifold, drawn into the combustion chamber, and then ignited by a spark plug. Most engine service requirements are very similar and can be handled by a dealer, automotive shop, or trained mechanic. If there is a retrofit repair needed, such as a faulty injector or loose compression fittings, these would be taken care of by the installer.
Do Conversions Increase my Maintenance Costs?
Converted vehicles require lower maintenance and HALF the normal oil and filter changes. Using CNG maintains the oil viscosity, causing less wear on various engine parts such as the pistons, valves, and the head walls. The gases are burned more efficiently emitting no harmful or filthy carbon deposits which keeps your oil cleaner. Using CNG also extends the life of the engine largely due to the containment of the oil film that collects on the cylinder walls. This containment prevents oil from transporting to other engine parts unlike engines running on gasoline or diesel.
- Gasoline CNG Conversion Kits run on either 100% gasoline or 100% natural gas (Bi-Fuel CNG Conversions). A CNG tank is added to hold the natural gas. The addition of another fuel tank doubles the driving range. Bi-fuel conversions greatly reduce your fuel and maintenance costs. Because the fuel combusts completely, your engine stays much cleaner. These conversions also reduce oil and filter changes. The cleaner burning fuel extends the life of your cars and trucks.
- Diesel CNG Conversion Kits blend a mix of both diesel and natural gas, Dual-Fuel. This greatly reduces the consumption of expensive diesel fuel. Expect an increases your mileage, and a reduction in maintenance of expensive oil and filter changes. The air/natural gas mixture is denser. This denser higher octane mixture creates more power and increased torque. The cleaner burning fuel extends the life of your trucks and buses.
Benefits to the Vehicle
Trucks & Cars Running on CNG
- Natural gas carries higher BTU levels than gasoline (125 vs. 90) due to ethanol and oxygenated fuel additives in the gasoline.
- Reduces the Fuel & Maintenance Costs Approximately 40%.
- Combusts without self-ignition and protects your engine from knocking, even on engines with higher compression and efficiency levels.
- Combusts 100% due to a proper air to natural gas mixture at ambient temperatures.
- The oil that lubricates the engine is less contaminated and reduces oil and filter changes in half.
- There are no sediments and the spark plugs are kept clean. Oil on the walls of the engine cylinders are not washed off.
- Combustion gases are not corrosive. By not damaging metals, the life of the exhaust pipe and silencers is longer.
- The gaseous nature of the fuel eliminates the scanning actions in the cylinders during fast acceleration periods, with the advantage of reducing the corrosion of metal surfaces.
- The engine presents great performance flexibility during accelerations without irregularities or backfires, even at low direct speed.
- Converted vehicles may switch from using CNG to gasoline by simply pushing a button while driving.
- CNG gasoline bi-fuel system doubles the car’s driving range.
- CNG conversions run smoother and more quietly.
- Vehicles operate in all terrains, even across mountains. For example, a truck with a 37-ton load drove above 4,800 meters high in the Peruvian Andes in May 2008.
- CNG works fine under any climate condition. Since the fuel does not freeze not even at low temperatures the vehicle will always be ready to be used.
- System is fully reversible and can be transferred to other vehicles after inspection
Three Main Components to a Vehicle Conversion
- CNG Conversion Kits
- CNG Tanks
- NFPA-52 Certified high pressure parts
The CNG tank can be mounted in several places. Most popular locations are in the trunk or in the bed of the truck. A high pressure fuel line routes the methane through a filter then to the engine department. The newly installed 2-stage regulator will reduce the high pressure down to ambient levels closer to 36 PSI. The added noise reduction injectors will then dispense the gas. This process is controlled by the system’s ECU which is programmed to dispense the natural gas to match car’s or truck’s original fuel mapping. Sensors and computers adjust the fuel-air mixture for peak performance. CNG conversion kits do not reduce your car or truck’s performance.
Fueling at CNG stations is just like you were fueling with gasoline or diesel and takes the same amount of time. The two tanks will double your driving range. You still need to use gasoline as this is required to start, lubricate, and warm the vehicle. CNG conversion kits are programmed to protect against excessive heat, and sudden changes in driving conditions. Should you need to break heavily, suddenly speed up, or hit a steep hill your fuel system will automatically switch back to gasoline for the needed additional power.
Converted vehicles work just like the original. Adding the new fuel system is completely non-invasive and easy to reverse. Sequential port injection systems from trusted manufacturers do not alter or interfere with any of the original engine manufacturer (OEM) factory settings or fuel system nor do they tamper with any engine devices or controls. Because there is no tampering, there is no violation with anti-tampering laws.
Source by Stephanie McGreevy