LUBRI CATION
Since the U.S. EPA issued its ultra low sulfur
diesel (ULSD) mandate in mid-2006 to help
lower emissions, diesel vehicles have experienced
a multitude of issues. Since 2012, all
non-road diesel fuel engines have also been
forced to use ULSD. Th is includes farm and
construction equipment, as well as locomotive
and marine applications.
Since the switch to ULSD, many fl eets and
service technicians have experienced one or
more of the following issues:
Lower energy content (BTUs) compared to
low sulfur diesel (LSD), resulting in lower fuel
economy.
30 Fleet Maintenance | AUGUST 2017
Because ULSD is hygroscopic, it absorbs
moisture from the air.
Reduced levels of lubricity.
Poor cold fl ow characteristics.
Aggressive chemicals causing corrosion.
Besides fuel quality and characteristic issues
like these, fuel systems can develop ULSD
related problems over time. Some of the most
common issues that fl eets and service technicians
face today are:
Rust and corrosion can form in lines and
tanks from the aggressive chemicals found
in ULSD.
Low fuel lubricity causes wear or scarring
in pumps and injectors.
Sludge can build up inside tanks and result
in plugged fi lters.
IDID
However, one of the biggest problems diesel
owners face can be the size of just a few
microns: internal diesel injector deposits
(IDID). Common in high-pressure common rail
fuel injectors, these deposits continue to show
up more frequently as manufacturers develop
injection systems with even tighter clearances.
Modern injectors are precision instruments.
With tolerances as small as 1 micron and as
many as 24 holes in the injector tip, any deposit
can rob economy and power.
IDID can be separated into two types: coking
and sticking. Coking deposits are formed on
the inside nozzle fuel fl ow holes and the tip of
the injector. Coking deposits have been around
well before ULSD, aff ecting fuel spray pattern
and fuel volume delivery.
Sticking deposits are found inside the injector
on internal moving parts. Th ese deposits aff ect
injection timing and fuel volume delivery.
Incompatibility of commonly used and
widely accepted corrosion inhibitors can lead
to both kinds of deposits. Additionally, trace
amounts of sodium have shown up in ULSD,
and many injector deposits are identifi ed as
carboxylate salts.
Injector deposits are nothing new, and with
varying quality fuel across the country and
injection systems constantly being developed
with tighter clearances, IDID promise to be an
issue for a while longer.
Fuel Additives
Both fuel quality issues and fuel system issues
can be addressed by incorporating a fuel additive
into a fl eet’s maintenance routine. Most
fl eets will cringe at having to take the time
to add a fuel additive at every fi ll up, but not
every additive needs to be used each time fuel
is added.
A fuel additive, such as Hot Shot’s Secret
Diesel Extreme, for example, addresses every
issue noted previously, including IDID, and is
formulated for use once every six months.
The Future
What’s next for the diesel industry? As diesel
emissions are scrutinized even more, the
EPA might push fuel manufacturers further
towards plant-based biofuels, such as biodiesel.
Both renewable and biodegradable, biodiesel
promises to be a viable option in the future.
Common biofuel sources like soy beans and
corn can still leave an impact on the environment
by requiring farmable land and freshwater
for its production.
According to ExxonMobil’s website, their
scientists have developed a strain of algae
that can convert carbon into record amounts
of energy-rich fat, which can then be processed
into biodiesel. While this algae process isn’t
new, it shows how far scientists are searching
for answers.
Issues With Ultra
Low Sulfur Fuel
Common problems that develop over time
By Chris Gabrelcik
PRESIDENT & CEO, LUBRICATION SPECIALTIES
The company (www.lubricationspecialties.com) provides
solutions with the formulation of new additives,
lubrication or equipment. With the development of
Hot Shot Secret Stiction Eliminator in 2004 followed
by Diesel Extreme, it has developed more than 30
additives, with a concentration on diesel performance
across multiple markets, including fleet, heavy duty
transportation, light vehicle, marine, powersports,
agriculture/construction, RV and industrial. Gabrelcik
is one of the few people worldwide to hold both the
certifications of Lubrication Specialist (CLS) and Oil
Management Analysis (OMA).
» Injector deposits affect fuel spray patterns,
leading to lower fuel economy and power.
Photo courtesy of Lubrication Specialties
IDID is a big problem.