The Effects of Diesel Fuel Contamination
Not only can these failures be
extremely costly to repair, but these catastrophic failures can be dangerous,
especially when they occur on the road or at high speeds.
Fortunately, many of these failures can
be prevented through preventative solutions such as a dependable Fuel Management Solution.
Let's take a look at the symptoms,
causes, testing, and solutions for diesel fuel contamination.
Symptoms of Fuel Contamination
Don't Ignore Your Engine Check Light
Many people have been or have known
someone that was in a situation where the “check engine” light comes on in
their vehicle out of seemingly nowhere. Anxious at first, they tone down their
driving to see if they can feel any difference in how the vehicle is running.
Strangely enough, it doesn’t feel any
different than before- so they convince themselves it probably isn’t anything
other than the truck being a bit “finicky”.
At first, a few days go by and then a
few months. The light is still on and since the vehicle
doesn’t feel to be running any different, it’s running just as often
and hard as it normally would.
However, under the hood, components are
not operating as designed and the continuous operation of worn parts is
damaging the very systems that keep the vehicle running.
At this point, detrimental engine
failure could be just a matter of time,
Clogged Fuel Filters
Frequently clogged fuel filters are
oftentimes one of the first initial signs of possible diesel fuel
contamination. The filter is designed to capture particles in your fuel before
they pass into the engine and these pieces of matter can be made up of clumps
of sludge, metallic particles, or other unwanted particulates.
If a fuel system is experiencing an
atypical recurrence of fuel filter replacements, the problem’s root could lie
in the quality of the fuel being supplied to the filter.
Heavily contaminated fuel would
consistently provide particulates and other undesired materials that quickly
clog filters, possibly leading to other issues in the fuel system.
This contamination could be stemming
from either the fuel source itself or from the internal corrosion of the very
fuel tank being used to fuel the engine.
Failing Fuel Pump
With frequent fuel filter clogging,
fuel pump failure is often to follow. Because of the restriction caused by the
clogged filters, the fuel pump could be working harder than designed to deliver
fuel from the tank to the engine.
While a fuel pump is failing, the fuel
pump will not be able to deliver a steady flow of fuel, interrupting the
mechanical stroke and function of the engine. This can be especially noticeable
under acceleration, where fuel demand is increased however the fuel pump is
unable to deliver the fuel at the requested rate.
Symptoms of a failing fuel pump may
include:
· Jerks
or sputters at high speeds
· Power
loss on acceleration
· Power
loss while driving up a slope
· Power
loss while towing
· Engine
surging while acceleration is not engaged
· Engine
will not fire
When a fuel pump is exerted to the
point of failure, it is past the point of simple maintenance to get the engine
running again. When a fuel pump fails, fuel line pressure is lost thus not
being able to deliver any fuel for the engine to fire up. Downtime of equipment
for major repair is expected at this point to get the fuel flowing properly
again.
The above diagram explains how
combustion in a diesel engine is achieved. During the combustion cycle, fuel is
injected into the cylinder and ignites, creating the energy needed to transfer
to the mechanical output that drives the vehicle or equipment.
Diesel fuel injectors are designed with
specific functional tolerances as per the truck’s manufacturer. If these
injectors begin to fail or veer from the designed tolerances in any way, then
the fuel spray trajectory within the combustion chamber is drastically
affected.
Catastrophic Engine Injector Failure
When catastrophic engine injector
failures are experienced, the engine fails to continue operation due to these
sudden occurrences. Typically, these experienced events can only be restored
through costly repairs that often result in prolonged equipment downtime.
Operations and equipment managers rely
on proper equipment functionality to maintain revenue margins and business
profitability. It is for these reasons that attention should be directed at
managing, predicting, and preventing these failures from occurring through
proper equipment maintenance and operation.
Equipment specialists and OEMs typically
operate their equipment around recommended maintenance procedures that are
designed to limit component failure and prolong equipment life.
It is common for OEMs to recommend
these maintenance procedures to uphold warranties. Fuel injector replacements
are a critical component to these OEM warranties, with recommendations often
being at the engine’s half-life. Using contaminated diesel, shortens the time
before an engine is considered to have reached half-life.
Although equipment maintenance
personnel are responsible for managing engine equipment and remediating
potential issues, not all can be predicted and/or prevented. This is often the
case with contaminated fuel, as operations managers are often not aware of the
quality of the fuel they are procuring or filling up with enroute.
With the use of contaminated fuel,
erosion of the injector valve seat is likely, resulting in a partial functional
failure that will eventually lead to a full functional failure of the fuel
injector valve.
The Failure Chain Reaction
· Contaminated
fuel is sent through fuel injectors
· Fuel
injector valve deterioration begins
· Fuel
pressure through injector nozzle reduces
· Fuel
volume through the injection system reduces
· Engine
ECU increases fuel load to compensate
· Reduced
fuel atomization
· Soot
generation within the cylinder
· Emissions
increased
· Experienced
power loss
· Partial
injection failure point
· Injector
wear continues
· Fuel
consumption increases dramatically
· Visible
and audible signs of engine distress
· Full
injection failure
To recap: Fuel injector nozzles are designed to spray a mist of fuel into the cylinder for piston compression and fuel combustion through precise inlets. When injector tolerances have been compromised, fuel droplets from the injector nozzle may not be able to achieve complete combustion, often resulting in smoke and soot emissions.
If the issue is not addressed, soot will build on the injector tips and eventually cause blockages. These blockages can also occur within the engine valves, cylinder walls, and exhaust system and lead to catastrophic engine failure.
Detect contaminated diesel directly from the tank
