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Diesel-Sure Test Kits (Testing for Paraffin)




Testing for Paraffin

Part number DSEN590

WHY TEST DIESEL for diluting with PARAFFIN

Economic supply and demand phenomena as well as efforts to make paraffin more affordable to the poor have resulted in a large price difference between diesel and paraffin. Unscrupulous fuel suppliers stand to make large profits by fraudulently diluting diesel with paraffin or simply selling paraffin as diesel . Although it is true that diesel is routinely cut back at refineries with small amounts of paraffin ( to improve flow qualities in winter). continuous operation with a substantial proportion of paraffin ( possibly 50% or more) will ultimately damage diesel fuel pumps, injectors and diesel engines. The lubricating properties of diesel are critical to the longevity of modern fine-clearance diesel injection systems. Paraffin's lubrication properties are far inferior and cannot be improved with engine oil. Moreover, adulterated diesel may have inferior ignition properties resulting in burnt valves and overheating.     

Manufacturers of engines and fuel injection systems are able to determine whether the presence of excessive paraffin dilution is responsible for equipment failure. At least seven major tractor suppliers have issued a joint statement to the effect that engine failures as a result of using adulterated diesel will not be covered by their warranties. Unfortunately adulterated diesel is not always easy to identify. It may look and even smell like regular diesel. The compact Diesel-sure test kit manufactured is designed to detect diesel that fails to meet the SABS 342 and EUROSPEC EN 590 diesel density specification as a result of the addition of a significant proportion of paraffin.

DIESEL-SURE TEST KIT Patent pending

Why Test Diesel?

Economic supply and demand phenomena as well as efforts to make paraffin more affordable to the poor have resulted in a large price difference between diesel and paraffin.  Diesel retailers stand to make large profits by fraudulently selling paraffin as diesel either by blending it with diesel or by blatant substitution.  Although most diesel engines will run on paraffin, continuous operation with paraffin causes long-term damage.  It is also illegal to run a vehicle on paraffin as it is considered a means of evading tax. The Diesel-sure kit is designed to detect diesel fuel that fails to meet the current SABS 342 diesel density specification as a result of substitution with significant proportion of paraffin.

APPARATUS

100ml Duran glass bottle with blue polypropylene cap and suspended housing containing a black pellet.

Testing Procedure
1.        Before undertaking any fuel test, tell the fuel pump attendant that you need to test diesel before making a purchase. Do not test fuel without the seller’s permission.  
2.        Ensure that the temperature of the unknown fuel is between 5°C and 30°C.
3.        Fill the glass container with unknown fuel up to the 80ml mark.
4.        Screw on the blue / White cap.
5.       Observe whether the pellet floats or sinks.  If the pellet does not float to the surface, this indicates that the fuel does not comply with the current SABS 342 standard.
6.       Observe the clarity of the fuel and check for contamination by water, which may exist in suspension, emulsion or as droplets near the bottom. Look for solid particles (dirt and mud) either suspended or as sediment at the bottom of the glass container (clear sign of poor quality fuel).
7.       if the fuel is acceptable, pour the contents of the glass bottle into your fuel tank. (Diesel-sure test kits are inert and will not contaminate fuel).  Do not store fuel in the glass container (it affects the polymers).

8.       Replace the cap (there is no reason to rinse the inside of the apparatus).

QUESTIONS AND ANSWERS

1.  Can a diesel engine run on fuel other than diesel?

The short answer to this question is yes. A diesel engine burns fuel without a spark by injecting an exact amount of fuel into a cylinder containing air which is made hot enough to burn the fuel by compression alone.  Hence diesel engines fall into the family o compression ignition engines as opposed to spark ignition engines.  Provide the fuel will burn at the temperature created by compression, the engine will run.  History shows that diesel engine have been manipulated to run on a variety of substances including sunflower oil in South Africa, coconut oil in Thailand, cotton seed oil, butter milk, turpentine and paraffin.  Nevertheless, these products may cause harmful long-term effects including; formation of carbon deposits and excessive wear, leading to eventual failure of fuel delivery pumps and injectors.

2.   What will happen if a diesel engine is run on paraffin?

There are reports of diesel engines that have run for hundreds of kilometers on unadulterated paraffin.  However, there are many cases where failures have occurred within a very short period. What is indisputable is that paraffin will ultimately damage a diesel engine.  Firstly, paraffin has far inferior lubricating properties to diesel.  Thus, fuel delivery pumps (which must be lubricated by the fuel they pump) will last only a fraction of their normal lives and injectors will wear faster and have an increased chance of blocking. A common symptom of running on paraffin is for one or more injectors to block and then explode.  Secondly, paraffin compromises the CETANE number of diesel and causes the engine to run at higher temperature often damaging engine valves.  Thermocouples placed in one turbo diesel engine indicated 20°C higher than the normal engine oil temperatures at both the turbo charger and the oil cooler inlet pipe when the engine ran on pure paraffin at less then half maximum output.

3.  Can the Diesel-sure test guarantee that the fuel contains no paraffin?

No.  The Diesel-sure test is designed to alert fuel buyers to instances where large proportions of diesel have been substituted with paraffin to the extend that fuel no longer complies with the SABS 342 density specification.  Manufacturers of diesel are entitled to - and may - blend small proportions of paraffin with diesel provided the product sold as diesel conforms to specification.

4.   Are there any other ways of establishing whether a fuel sold as diesel contains a large proportion of paraffin?

Yes. There are proprietary testing kits which are capable of detecting chemical markers which may be used for the identification of petroleum products that can be illegally substituted for more costly and higher taxed diesel. However sourced from neighboring SADC countries is unlikely to contain any markers.  Moreover, these test kits contain toxic substances, are expensive and the execution and interpretation of the test is time-consuming, complicated and impractical for lay people.

When running on fuel containing a high proportion of paraffin, it may also be possible to smell a distinct aroma of burnt paraffin.  The smell is similar to that of jet exhaust surrounding airports.  This paraffin smell is sometimes detectable when idling or driving slowly and can often be smelt if driving behind another vehicle that is running on paraffin.

SOME PRACTICAL SUGGESTIONS DO’S AND DON’TS

Always tell the pump attendant that you need to test the fuel before the purchase and obtain his/her consent before testing.  
Try to buy fuel from reputable retailers with well-known brand names who have a large turnover and good housekeeping.
Whenever possible, top up fuel tanks at the end of the day.  Half-full tanks contain large volumes of moist air.  As temperatures drop during the night, this moisture condenses against the tank walls and collects at the bottom of your fuel tank.  Water is the enemy of a diesel engine.  It corrodes metal and promotes the growth of bacteria at the water/diesel interface.  
If your diesel tank or fuel filter has a sedimenter, drain it and/or flush it often

To expel water and dirt before it reaches the fuel filter.

Familiarize yourself with the physical characteristics of different diesel fuels - color, smell, clarity as well as the way it refracts light and the way it foams when poured into your tank.  By doing this, you are more likely to recognise fuel that may harm your engine.

When traveling through third-world countries, fill your tanks frequently with tested fuel to avoid being forced to purchase sub-standard fuel out of necessity.
Before filling, watch the local activity and fill your tank from a pump that is popular with local residents.
When traveling through third-world regions, always carry a couple of extra replacement fuel-filters in case you inadvertently buy contaminated diesel (which can block fuel filters).

Before traveling to remote regions, consider carrying extra fuel in jerry cans and/or fitting additional long-range fuel tanks to your vehicle.  However it should be borne in mind that several SADC countries have placed restrictions on extra fuel imported via these means.  Furthermore, extra tank volume increases the risk of water gain and fuel decomposition.


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