TM 9-6115-624-BD
of fuels, increased by vaporization during filing, the blending process is very important. The most direct and expendient
procedure to mix fuels is to add the two fuels at the same time from two separate fuel lines. If added directly to the
vehicle fuel tanks as separate fuels there is not sufficient turbulance in filling or shaking by normal driving to provide a
properly mixed fuel. In vehicles with more than one tank, you could end up with a distinct fuel type in each tank.
D-2. Fuel Blending . In following the blending procedure it must be remembered that the basic fuel is the better of the
two fuels and the extender is the poorer. The blending fuel is the extender. While you can use up to 50 percent (half
and half) of the extender you should not use more than is needed to obtain the supply needed. Also, ensure a fuel tank
or container is available to hold the quantity of fuel needed to perform the mixing operation.
a.
Blending Procedure. The preferred location to accomplish blending is at a fuel dispensing site or in fuel
dispensing vehicles that utilize their own pumps. The least desirable is using vehicle's fuel tanks. Blending in vehicle
fuel tanks should only be done as a last resort because it is imprecise and time consuming.
(1) Blending in fuel dispensing vehicles. Add the blending fuel to the fuel tank and mix by reconnecting the
pump inlet hose to the vehicle and recirculating the fuel for a minimum of 15 minutes.
(2)
Blending in 55 gallon drums. Add the blending fuel directly into a drum and mix by rolling the drum.
(3) Blending in gravity feed tanks (stationary) not equipped with fuel transfer pumps. Blending fuel can be
added manually or by using the pump and meter of a fuel dispensing vehicle. Add the blending fuel and mix by
recirculating from the tank outlet to the tank truck pump inlet.
NOTE
Blending in the fuel tanks of using equipment and vehicles should be undertaken only as a last
resort. Add both fuels to the fuel tank at the same time with dual nozzle, or from fuel cans.
b.
Elimination of POI Substitute Fuel After Use. If expedient fuels are not used completely during the operation,
they should be drained or pumped out. Fill the vehicle fuel tanks with 10-15 gallons of an approved primary fuel and run
the engine for at least 1/2 hour. Operate the engine under a load or drive the vehicle a sufficient distance to bring the
engine up to operating temperature.
D-3. Lubricants and Hydraulic Fluids . This section lists a few elementary characteristics of importance although there
are no expedient means of measuring or predicting them. A list of basic fluids which can be used is provided in order of
priority. Cautions on incompatible fluids are mentioned and a means suggested to flush the system.
a.
Substitute Lubricants and Hydraulic Fluids. Table D-2 provides a list of basic fluids which can be used as
substitutes (alternate and expedient). It is structured around the vehicle lube order. Alternate products shown are NATO
equivalents to the US specifications and can really be considered primary fluids. There are no corresponding ASTM
designators. The expedients are emergency only substitutions. They may cause one of three problems either
individually or in combination.
(1)
They may not allow proper or efficient operations because of improper viscosity.
(2)
They may cause high wear rate because of improper viscosity.
(3)
They may cause seal damage or create deposits because of improper chemical composition.
b.
Time Limit on Use of Substitute Lubricants and Hydraulic Fluids. There are no established time constraints on
these expedients but the shorter the time used the better.
D-4. Flushing Lubricant and Hydraulic Systems.
Expedient lubricant and hydraulic fluids must be removed as soon
as possible, and the system cleaned and inspected.
a.
Flushing Oil Systems. For those systems using oil, flushing involves draining, refilling with the proper
product, operating to insure complete circulation and when possible stable operating temperature (this usually means at
least 1/2 hour), a redrain and a refill. For the transmission and hydraulic system
D-2
