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Lessons Learned Provide Opportunity
Winter of 2006-2007 is over and winter 2007-2008 is closing in. Now it's time to reflect on the problems encountered during cold weather and
the use of ultra low sulfur diesel fuel. Any fleet running trucks in the northern states, more than likely, encountered some issues that can be traced to the use of ULSD. Most fuel
problems involved premature gelling of ULSD fuel in low temperatures, not the extreme low temperatures encountered in the past. Fleets affected also found that a lot of fuel additives used in
prior years would not lower the pour point of ULSD to the same level as years past. Testing several brands of fuel additive would be difficult so most fleets relied upon their past suppliers
and took the risk of finding out the hard way just how low the temperature needed to get before problems occurred. Fleets found that doubling and tripling the additive had little effect on
lowering the pour point of ULSD much below the single dose treatment. The traditional practice of blending #1 and #2 fuels was not an option in most areas because of the limited supply of ultra
low sulfur kerosene.
When the temperatures fell into the single digits, truck operation problems compounded. Batteries and starters were pushed to the limit
resulting in wrecker bills and extended wait times at dealers and other repair vendors. Companies providing road service to fleets were also stretched to the limit.
Some brands of engines running on ULSD started easier and responded better than others in the extreme low temperatures. However, it's safe to
say, most diesel powered trucks operating in the extreme low temperature had their own sets of problems. Starting trucks in cold areas with strict anti-idling rules was also an added concern.
Fleet managers were surprised to discover even trucks with block heaters plugged in had problems. Trucks would start OK, but would not
stay running long enough to warm the fuel in the tank, the fuel lines, and fuel filter. Affected trucks would run for 10 to 15 minutes and shut down due to fuel gelling in the fuel system
between the fuel filter and the fuel tank. Some fleets had trucks get twenty to thirty miles out and shut down due to fuel tank temperatures being low enough to promote gelling in fuel lines
and filters.
Even duel draw fuel systems encountered gelling problems between the tank and engine, most notably creating an uneven fuel return condition
which resulted in fuel tanks over flowing on one side and running out of fuel on the other side.
One thing is for sure, blaming the fuel suppliers and EPA will not do any good. ULSD is here for the long haul, figuring out how to deal
with it before next winter is about all fleets can do to prevent a repeat of this winter's woes.
One fleet in the Midwest is not waiting for the beginning of next winter to start working on a solution. The anti-idling rules, high idle
percentages for the fleet, and driver hotel niceties, had the fleet already looking and testing engine powered Auxiliary Power Units. The negative aspects of running an engine powered APU
prompted the maintenance director to look at battery powered systems. After going through the winter and experiencing the added problems contributed to ULSD, plans got underway to come up with
a total system that would provide creature comforts with the engine off and ensure the truck would start and stay running in low, single digit or below, temperatures. The maintenance
director found the outside help he needed and assembled a total system using a battery powered APU. His goal was to, not only cool the truck in warm weather but, heat the sleeper bunk, the fuel
water separator, the engine block, as well as, circulate warm fuel from the fuel water separator back to both fuel tanks while the truck is unattended.
The heating system, while being controlled by the bunk controls, will operate full time to accommodate driver occupied time. An extra
pump is included to capture the thermal energy from the engine after shut down. A thermostat allows pump operation until the engine temperature falls below 110 degrees. At that point the
diesel fired heater fires up and continues the heating process.
In unattended mode the heating system operates on a seven day timer allowing the heater to fire up according to timer settings and run for two
hours each selected day.
The decision was also made to put the power inverter on the auxiliary batteries to ensure the truck would not be sharing its battery power with
driver hotel niceties. The truck alternator was upgraded to 170 amps to keep both battery sets charged while the truck engine is running. Batteries are deep cycle and long life.
Battery life will depend upon several factors, some yet to be determined.
With the help of Jeff McCord of Espar Heater Systems, Greg Landuyt of Lubrication Specialist, and Steve Emery of Fontaine Modification Centers
the components were assembled, installed and tested. The weather cooperated by dropping the temperature down into the low twenties so testing of the heating system could be conducted in real
world conditions. The truck had already been sent to south Texas to test the cooling part of the system a few days earlier. The combined results were favorable enough to prompt the fleet
to work and get the system installed on new trucks with 07 emission engines.
Even though nobody responsible for fleet maintenance looks forward to winter, this fleet is well on its way to ensure the trucks will start and
run under most conditions, provided the snow plows are running.
If you would like to respond to this article or inquire on how to assemble a similar unit, respond to m2dick@rmsinternationalinc.com, we'll put you in touch with the right people. You can also view a video of an installation by clicking on this link. View Video
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