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Autogas for Vehicles & Forklifts

• What are the benefits of converting a vehicle to LPG?
• Is it safe to use a domestic exchange cylinder for an Autogas supply?
• When a vehicle is dual fuelled, (LPG and petrol), is there likely to be any reduction in fuel efficiency?
• Will I lose any performance by changing over to LPG?
• Will changing over to LPG effect any warranty provided by the vehicle manufacturer?
• What are the benefits of operating forklift vehicles on LPG?
• What other vehicles can be converted to operate on LPG?

The following are the benefits of converting vehicles to LPG:

• Generally the price of LPG is lower than petrol giving a cost advantage to the vehicle owner.
• Unlike petrol, which enters the engine as a fine mist, LPG enters the engine as a gas. This means that under cold start conditions the unburned petrol washes down the cylinder wall diluting and removing the lubricating oil. LPG therefore extends the life of the oil and decreases engine wear. In addition to this the clean burning properties of LPG extend the life of spark plugs.
• LPG is good for the environment it contains no lead and produces less carbon monoxide, oxides of nitrogen, carbon dioxide, and particulate matter.

Is it safe to use a domestic exchange cylinder for an Autogas supply?

In general the answer is no. The reasons are listed below:

• Domestic cylinders are generally not properly secured into the vehicle and this makes them vulnerable in a crash situation.
• The domestic cylinder valve arrangement is incorrect for the proper operation of the vehicle fuel supply requirements.
  1. The cylinder valve is not provided with excess flow protection, which means that if the valve or supply line is sheared in a crash situation, there will be an uncontrolled flow of LPG into the vehicle interior.
  2. The domestic cylinder valves and the attachments which are typically being used to connect domestic cylinders into vehicles are generally not designed to operate under liquid LPG condition and therefore may not be suitable for the use which is being applied.
  3. The interior of a vehicle can become very hot in some climates. This means that there is a potential for the safety relief valve of the cylinder to open and release excess pressure, again creating a safety hazard within the interior of the vehicle.
  4. In some cases the cylinders are not provided with a safety valve. The flexible connection between the cylinder and the steel line to the engine forms a weak link in the piping system and is therefore vulnerable to rupture, leading to LPG entering the vehicle space.
  5. The design of the gas converter or gas regulator, installed within the engine space that provides fuel to the engine, is generally designed to take liquid LPG and convert it to vapour LPG. Usually a small bore copper or steel line is used to transfer the LPG from the cylinder in the rear of the vehicle to the engine. This is because domestic cylinders are installed into the rear of the vehicle in an upright or lying-on-the-side position.
  6. In both the above cases, only vapour gets transferred from the cylinder to the engine. This is because the cylinder does not have an internal tube that takes the liquid LPG from the cylinder into the supply line to the engine. Due to this, the engine gets starved for fuel during increased load conditions like accelerating or climbing up a slope.

Will changing over to LPG effect any warranty provided by the vehicle manufacturer?

Most vehicle manufacturers recognise the viability of LPG as an automotive fuel and continue to maintain the warranty on engines properly converted to LPG use where the installation and equipment meet all local standards. If there is any doubt check with the vehicle manufacturer or vehicle agent.

What are the benefits of operating forklift vehicles on LPG?

Firstly, the stop start nature of the forklift operation makes the use of LPG a favourite with forklift users, where the cold start and short running of these vehicles produces excessive engine wear. Secondly, the other benefit of operating these vehicles on LPG is the reduction of the exhaust gas emissions compared to diesel and petrol fuelled vehicles. In the generally enclosed environment that forklifts vehicles operate in, emission reduction plays an important part in the health of the workers and improved environmental hygiene, reducing the potential of damage to sensitive products. However it should be remembered that proper ventilation must still be maintained and that the general reduction of exhaust emissions does not preclude the necessity to provide a safe operating and well ventilated working environment.

What other vehicles can be converted to operate on LPG?

Many small engines are converted to operate on LPG including floor sweepers, small tractors, and larger applications such as airport service vehicles, buses, and trucks. LPG is also used a fuel for stationery engines such a generator sets, and pumping applications.