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Fuel systemÖ

The fuel system comprises the fuel cap, the filler pipe which leads to the fuel tank, the fuel tank itself, the fuel pump (which is often contained in the fuel tank), the fuel line from the fuel tank to the engine bay, the fuel filter, the fuel injection system (or the carburettor in the case of naturally aspirated vehicles) and, finally, the combustion chambers.

The main contaminants of the fuel system are the particulate contaminants in the fuel itself, which are the reason for the need for a fuel filter, the gummy deposits that accumulate in the fuel injectors over time as a result of the fuel constantly passing through them and the carbon deposits that accumulate in the combustion chambers over time as a by-product of the fuel combustion.

Left unchecked, all of these contaminants will diminish the effectiveness and efficiency of the fuel system, resulting in poor fuel economy and requiring expensive repairs.  However, the fuel system is best maintained internally with a high-quality fuel additive so that components like the fuel injectors never need to be disassembled.  This same fuel additive can prevent carbon deposits from forming in the combustion chambers.

A little attention paid to your vehicleís fuel system will ensure that you get the best possible performance and fuel economy from your vehicle on an ongoing basis.  Here are all of the things that are important to pay attention to:

Donít let fuel stain your vehicleís paintwork when filling upÖ

After filling up the fuel tank with fuel at the service station and putting the fuel cap back on the filler pipe to the fuel tank, itís important to wash the area right around the fuel cap down with water from a plastic watering can, which is normally on hand, to remove any traces of fuel which may have spilled onto the vehicleís paintwork or onto any other parts of the vehicle while filling the fuel tank.

Fuel spilled on the paintwork or other parts of the vehicle can cause permanent staining if itís not washed off.  It doesnít take very long at all to permanently stain the paintwork and the result is very unsightly.  Itís best to wash the area right around the fuel cap down in this way as a precaution even if youíre not aware of having spilled any fuel onto the paintwork or other parts of the vehicle.

If you are aware of spilling fuel on the paintwork or other parts of the vehicle in the course of filling the fuel tank, donít wait until youíre finished filling the fuel tank to wash the fuel off with water like I did once.  After continuing to pump the fuel until the tank was full, replacing the fuel cap on the filler pipe and then washing the spilled fuel off of the paintwork, polyurethane bumper, tyre and wheel, I discovered to my horror that I had barely stopped the fuel from staining the paintwork.  It literally takes less than two minutes for the fuel to stain the paintwork in this way.

So if you spill fuel while pumping fuel, hang the fuel nozzle up, even if you havenít finished filling the tank, put the fuel cap back on the filler pipe to the fuel tank and wash the fuel off with water immediately.  After washing it off, you can finish filling the fuel tank with fuel.  Next time, Iíll take my own advice.

Use GreenSky fuel conditioner to clean the fuel systemÖ

Use GreenSky 3-in-1 fuel conditioner every time you fill up your vehicle with fuel to keep the fuel system free of carbon deposits, varnish and gummy deposits from the fuel.  This includes the fuel injection system and extends to the combustion chambers in the cylinders which are also kept free of carbon deposits through the use of this fuel additive. The net result of all of this is more efficient operation of the fuel injection system, smoother engine performance and better fuel economy.

Itís important to keep the combustion chambers free of carbon deposits because they interfere with the correct combustion of the fuel according to the preset ignition timing.  Hot, glowing carbon deposits in the combustion chambers tend to ignite the fuel/air mixture earlier than it otherwise would be by the spark plug, which impedes fuel economy.  This is also known as pre-ignition.

What ends up happening is that the force generated by the early combustion of the fuel opposes the movement of the piston which is still on the up-stroke rather than driving it downwards on the down-stroke as it should.  This opposition between the piston moving upwards and the early combustion of the fuel generating force downwards can lead to serious engine damage.

The use of GreenSky 3-in-1 fuel conditioner also improves upper cylinder lubrication and thereby reduces wear in the cylinders where the piston rings meet the cylinder walls.

It makes a lot more sense to use a high-quality fuel additive like GreenSky fuel conditioner every time you fill up the vehicle with fuel to keep the fuel injection system clean all the time than it does to pay a mechanic so many hundreds of dollars to pull the fuel injection system apart and clean the fuel injectors of carbon deposits, varnish and gummy deposits from the fuel.  Itís a lot cheaper also, costing less than 1 cent per kilometre.  The fuel injection system contains precision-engineered components which are much better off being cleaned internally by a high-quality fuel additive than being disassembled, cleaned and reassembled.

A sure sign of a vehicle thatís maintained properly and correctly is that thereís seldom a need to pull anything on the vehicle apart, apart from expected routine auto maintenance.  I personally use GreenSky 3-in-1 fuel conditioner every time I fill up with fuel so that, among other things, I never have to disassemble the fuel injection system.

The easiest way to dispense GreenSky fuel conditioner into the fuel tank is to keep the following items in a plastic carton in the boot of your vehicle:

  • Two 360mL (12 ounce) containers of GreenSky fuel conditioner which will last about 20 tanks of fuel based on fills of 45L (12 gallons) and an application rate of 30mL (1 ounce) of GreenSky fuel conditioner per 38 litres (10 gallons) of fuel which equates to about 32mL of additive per 40L of fuel.  (One ounce is approximately 30mL and 1 gallon is 3.8L.)
  • A small, air-tight, plastic container with a lid that locks closed for holding approximately 50-100mL (2-3 ounces) of GreenSky fuel conditioner.
  • Two 25mL (1 ounce) plastic syringes in a labelled, snap-lock bag for filling up with the correct volume of fuel additive out of the above, opened, plastic container (holding approximately 50-100mL (2-3 ounces) of fuel additive) and for dispensing the fuel additive into the fuel tank.  You can purchase these plastic syringes from your local chemist, pharmacist or drugstore.

    You can also keep several other plastic syringes as spares in a separate, labelled, snap-lock bag because after about four uses, the fuel additive will dissolve the volume scale marked on the outside of the plastic syringes so that you canít read it, which renders them useless for measuring out the correct amount of fuel additive to be used.

After dispensing the fuel additive into the fuel tank from the plastic syringes and screwing the fuel cap back on, itís important to wash the area around the fuel tank opening down with water to wash away any fuel additive that may have spilled onto it.  The fuel additive can dissolve the paintwork in the same way that it removes deposits from inside the fuel injectors and combustion chambers.

Change the fuel filter every 12 months or 20,000 kilometres, whichever comes firstÖ

Change the fuel filter every 12 months or 20,000 kilometres (12,000 miles), whichever comes first.  Itís best to change the fuel filter every twelve months even if as little as 10,000 kilometres (6,000 miles) has been driven.  A blocked fuel filter can cause the electric fuel pump to fail prematurely.  This pump is often located inside the fuel tank itself and is therefore often hard to get to and expensive to replace.  In contrast, replacing the fuel filter is relatively inexpensive.  So itís good insurance and a small price to pay to simply change the fuel filter every 12 months or 20,000 kilometres (12,000 miles), whichever comes first, to prevent the electric fuel pump from failing prematurely.

If your vehicleís engine has electronic fuel injection (EFI), be sure to relieve the high fuel pressure in the fuel lines connected to the fuel filter, according to the instructions in the workshop manual for your specific vehicle, before disconnecting these lines from the filter.  An engine with EFI operates with a much higher fuel pressure in the fuel lines than an engine with a carburettor.

Failure to relieve the pressure in the fuel lines will result in fuel spraying out everywhere (including into your face and over your clothes) at high pressure from the hose fittings connected to the filter as you unfasten them.  This is very unpleasant and is best avoided.  Even after the pressure in the fuel lines has been relieved, itís still worth placing a rag over the hose fittings at the filter when disconnecting them so as to capture any fuel that might still spray out.

Change the air filter regularly at the required service interval...

Change the air filter at the service interval specified in the ownerís manual or workshop manual for your particular vehicle or even sooner.  A clogged air filter will have a detrimental effect on fuel economy because insufficient air will flow to the combustion chambers to enable the fuel to burn, which results in wasted, unburnt fuel and less power being supplied to the wheels.

Better still, purchase a high-quality, reusable K&N air filter for your vehicle.  A K&N air filter captures smaller particles of dirt than a disposable filter can and also, amazingly, increases the air flow to the engine, enabling more efficient combustion of the fuel, which leads to better fuel economy and more power when needed.

One outstanding benefit of this brand of filter is that itís guaranteed to last for ten years from the date of purchase.  It also requires very little maintenance.  Cleaning and re-oiling it once a year is more than adequate to keep it in peak condition.  This sure beats purchasing a new disposable air filter every six to twelve months and results in much better engine performance and fuel economy.  The website for K&N air filters is www.knfilters.com.

Check the engine idle speed every 12 months or 20,000 kilometres, whichever comes firstÖ

Check the engine idle speed every 12 months or 20,000 kilometres (12,000 miles), whichever comes first, and set it correctly according to specifications if you find that itís out of adjustment.  An excessively high engine idle speed causes excessive fuel consumption and poor engine performance which obviously means poor fuel economy.

The correct idle speed for a vehicleís engine can be found on the Vehicle Emission Control Information label on the underside of the front of the bonnet, provided that the engine in the vehicle is the original, factory-fitted engine or one identical to it (such as a reconditioned engine of the same type).  Refer to a workshop manual for your particular vehicle for the correct procedure and the equipment required for setting the engine idle speed.

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Copyright 2016 Andrew Mackinnon.  All rights reserved.