NOTICE.
Fuel system prime cycle may need to run 4-5 times after prolonged storage.
6. Allow engine to idle until the system equalizes pressure in the fuel lines and rails.

NOTICE.
If the engine runs rough, do not drive vehicle until engine runs smoothly.

2.4. Vehicle Fueling
NOTICE.
These are general fueling guidelines. Always consult fuel station personnel or
postings for specific fuel dispenser operating instructions and procedures.

2.4.1.

Fuel Properties and Quality

The 6.0L V8 engine is designed to operate on CNG. Clean burning CNG offers reduced
emissions for cleaner air and lower vehicle operating costs.
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.⚠ WARNING.

 Wear approved eye protection when fueling.
 CNG is flammable. Keep sparks and open flames away from CNG. Do not smoke
while fueling vehicle.
 Natural gas is colorless, odorless, and highly flammable. An additive like the
odor of sulfur or rotten eggs is added to CNG to alert to the presence of a gas
leak.

The engine and fuel system require high quality CNG free of dust, oil, or other
contamination.

.⚠ CAUTION.

Use of CNG not meeting SAE J1616 quality standards, or operator failure to properly
cap and clean fueling system connections may decrease engine performance and
damage vital Hexagon Agility® system components or emission controls. Damage to
components resulting from fuel contamination is NOT covered under warranty.

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2.4.2.

Fueling Procedure

.⚠ WARNING.

 Operators must memorize vehicle 1/4-turn manual shutoff valve location and
cylinder manual valve locations. FIGURE 4 Operators untrained or inexperienced
with filling a Hexagon Agility® CNG equipped vehicle should consult a qualified
CNG station operator.
 Never connect fuel fill nozzle to fuel receptacle if O-ring is missing or damaged;
this could cause serious injury or property damage.

Referring to Section 2.3.3., perform the following steps to fuel the vehicle.
1. Turn engine OFF and set parking brake. If required: set wheel chocks.
2. Ensure no open flames or ignition sources are present.
3. Remove dust cap from fuel fill receptacle. FIGURE 8
4. Wipe fuel fill receptacle and fill nozzle. FIGURE 8

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NOTICE.
Check for signs of oil or other contaminants. An oily or dusty condition may
be an indication of poor fuel quality or a station that is not well maintained.
Report unsatisfactory conditions to the station operator.
5. Inspect fuel receptacle O-ring.

.⚠ CAUTION.

Verify O-ring is seated in groove and is not damaged or missing. If a new Oring is required, it may be obtained from Hexagon Agility®. Please refer to
“Support, Service, or Parts” above to order.
Connect fill nozzle to fuel receptacle. FIGURE 8

NOTICE.
If natural gas odor is present, the fuel receptacle O-ring may be worn or
damaged.
6. Turn nozzle valve to “FILL” position and CNG will begin to flow.
7. Continue filling until fuel station dispenser shuts off automatically.
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8. Carefully disconnect filling nozzle from fuel receptacle by rotating fill nozzle valve to
the “VENT” position.

NOTICE.
Fuel receptacle is designed to prevent nozzle from disconnecting while under
pressure.
9. Return fueling nozzle to dispenser.
10. Install dust cap on fuel fill receptacle. FIGURE 8

NOTICE.
Drive Away Protection (DAP) safety interlock requires fuel receptacle dust cap
be in place for engine to start.

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2.4.3.

Fast Fill vs. Slow Fill and Pressure/Temperature Relationship

CNG stations typically fill to a service pressure of 3600 psi (250 bar). During fast filling, it
is normal for gas to heat up as it compresses inside the cylinder(s). On a hot day, pressure
from the filling station will indicate a 100% full cylinder with a system pressure of 3600 psi
(250 bar), but the fuel cylinders may not be filled completely.
For example, when the ambient temperature is 120°F (50°C) in the afternoon, the CNG
dispenser stops at 3600 psi (250 bar) as expected. However, later that evening ambient
temperature drops to 70°F (20°C). As the CNG cools, pressure in the cylinder(s)
decreases. Therefore, instead of having a complete fill of 3600 psi (250 bar) at 120°F,
cylinder pressure is about 3000 psi (207 bar) at 70°F (20°C) or approximately 83% full.
Fueling stations can partially compensate for the heat generated during fast filling, but
generally cannot achieve more than 70% to 80% fill rates. On the other hand, slow filling
results in nearly 100% full, because the CNG can cool during the filling process.

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2.4.4.

Fueling Station Locations

Public and private CNG filling station locations are listed on the following U.S. government
website:

http://www.afdc.energy.gov/locator/stations/

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3. Service and Maintenance
3.1.

Recommended Fluids

The Hexagon Agility® CNG fuel system is a purpose built for medium duty compressed
natural gas operation. Proper maintenance is critical to protect your investment. Poor
maintenance can lead to premature engine wear and fuel system damage. Keep records
to document proper maintenance as outlined in this manual. Failure to properly maintain
fluids can result in costly repairs not covered by warranty.

.⚠ CAUTION.

The use of OEM recommended fluids is critical to proper engine and fuel system
operation and longevity. Failure to use correct fluids can lead to engine and fuel
system damage not covered by warranty.

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3.1.1.

Fuel System Coolant

The Hexagon Agility® pressure regulator is supplied with coolant from the OEM coolant
system.

.⚠ CAUTION.

Follow OEM recommended coolant specifications.

.⚠ CAUTION.

Do not use well water to mix with coolant. Well water contains minerals which
promote cooling system electrolysis; this can cause premature cooling system
damage.

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3.2.

Maintenance Schedule

Hexagon Agility® has established the following maintenance intervals to ensure safe and
reliable engine fuel system operation. For questions regarding engine and fuel system
service and maintenance please refer to the Hexagon Agility® website for the latest contact
information.

Required Engine & Fuel System
Service

Years

Interval*
mi.

km

Replace spark plugs

n/a

50000

80000

Drain and change LP fuel filter element

n/a

5000

8000

Drain and change HP fuel filter element

n/a

7500

12000

Inspect CNG cylinders and mounts**

1

100000

161000

Visually inspect all CNG hoses and lines**

1†

100000

161000

*Vehicles operating in harsh environments may require more comprehensive or more frequent
inspections.
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**Check with Authority Having Jurisdiction for additional cylinder and/or fuel system inspection
schedule requirements. Refer to Section 3.2.1.
†All CNG hoses must be inspected every month or 200 hours.

.⚠ WARNING.

Personal injury or death could result from neglecting to perform the above
recommended services.

.⚠ CAUTION.

Failure to perform the above services according to manufacturer recommendations
may void fuel system warranty.

NOTICE.
The above services must be performed by trained professionals.

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3.2.1.

CNG Fuel Cylinder and Fuel System Inspection Requirements

U.S. Federal Motor Vehicle Safety Standards (FMVSS) Section 304 requires visual CNG
cylinder inspections every 12 months or sooner.

.⚠ CAUTION.

Inspections must be performed by certified inspectors using guidelines from the
fuel cylinder manufacturer in addition to the guidelines listed in this manual.

.⚠ WARNING.

If a CNG-fueled vehicle has been involved in an accident or fire, the system and
cylinders must be inspected by a certified (CGA C-6.4 or other) CNG fuel system
inspector.

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For detailed fuel system inspections, Hexagon Agility® recommends two practical fuel
system inspection schedules–to be selected by the vehicle owner:
1. The common industry recommendation of every 3 years or 36000 miles, whichever
occurs first,
OR
2. After every 1 year or 100,000 miles, whichever occurs first.
In addition, Hexagon Agility® recommends a daily walk-around or pre- and post-trip visual
inspection be performed, regardless of which detailed fuel system inspection schedule is
followed. Refer to Section 2.1. Pre-trip Inspection.

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4. Warranty
The following warranty is, to the maximum extent permitted by law, the sole and exclusive
warranty made by Hexagon Agility® and is expressly in lieu of any other warranties,
remedies and conditions by operation of law or otherwise, whether oral or written, or
expressed or implied, including any implied warranty of merchantability and fitness or fitness
for any particular purpose or use. This warranty is made by Hexagon Agility® solely to the
original Customer, is not transferable or assignable by the original Customer and is
conditional upon proper installation (if applicable), operation and use by Customer. Hexagon
Agility® warrants the products to be delivered pursuant to any purchase order between
Hexagon Agility® and Customer to be free of defects in design, materials and workmanship
under normal use and service within the other limits described below. The warranty period
(the “Warranty Period”) shall be:

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1)

For a period of three years (36 months) or 60000 miles, whichever comes first,
from the verified vehicle in service date, Hexagon Agility® warrants the:
a. Engine Fuel System – fuel rails, injectors, fuel injector spacers.
b. Chassis Mounted Fuel System – fuel cylinders, cylinder mounts, fuel lines,
valves, solenoids, pressure regulator, PRD vent lines, PRDs, wiring harness,
electrical components supplied by Hexagon Agility®.
Hexagon Agility®’s obligation covered in this limited warranty is limited to the repair or
replacement of such parts as shall, under normal use and service, appear to have been
defective in workmanship or material. This warranty is applicable to Hexagon Agility®
products that are registered and operated in the United States of America, Canada and
Mexico. This warranty shall not be enlarged, nor shall any obligation or liability of Hexagon
Agility® be created, by Hexagon Agility® providing technical advice, facilities or service in
connection with any product. The Warranty Period begins on the date the vehicle is
delivered to the first user (“in service date”).

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THE REMEDIES SET FORTH HEREIN ARE EXCLUSIVE. UNDER NO
CIRCUMSTANCES, AND IN NO EVENT, WILL HEXAGON AGILITY®, INCLUDING ANY
OF ITS DIRECT OR INDIRECT SUBSIDIARIES OR AFFILIATES, BE LIABLE TO
CUSTOMER OR ANY OTHER PERSON OR ENTITY FOR PERSONAL INJURY OR
PROPERTY DAMAGE OR ANY OTHER LOSS, DAMAGE, COST OF REPAIRS OR
INCIDENTAL, PUNITIVE, SPECIAL, CONSEQUENTIAL, DIRECT, INDIRECT,
EXEMPLARY, COMPENSATORY OR LIQUIDATED DAMAGES OF ANY KIND,
INCLUDING WITHOUT LIMITATION COSTS, LOST REVENUES OR LOST PROFITS,
WHETHER BASED UPON WARRANTY, CONTRACT, STRICT LIABILITY, NEGLIGENCE,
TORT LIABILITY, OR ANY OTHER CAUSE OF ACTION ARISING IN CONNECTION WITH
THE
DELIVERY,
DESIGN,
MANUFACTURE,
SALE,
TRANSPORTATION,
INSTALLATION, USE, FAILURE, REPAIR OR REPLACEMENT OF ANY PRODUCTS
SOLD BY HEXAGON AGILITY® OR ANY OTHER CAUSE WHATSOEVER. BY
ACCEPTING DELIVERY OF THE PRODUCT(S) SOLD TO CUSTOMER, CUSTOMER
HEREBY (1) ACCEPTS THIS LIMITATION OF REMEDIES AS REASONABLE AND
ENFORCEABLE AND (2) EXPRESSLY ACKNOWLEDGES AND AGREES THAT
HEXAGON AGILITY®’S (INCLUDING ITS DIRECT OR INDIRECT SUBSIDIARIES AND
AFFILIATES) AGGREGATE LIABILITY, IF ANY, SHALL BE LIMITED TO, AT HEXAGON
AGILITY®’S OPTION, THE COST OF REPAIR OR REPLACEMENT OF THE APPLICABLE
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PRODUCT, OR, IN LIEU OF SUCH REPAIR OR REPLACEMENT AT HEXAGON
AGILITY®’S OPTION, A REFUND OF THE NEW SALES PRICE OF THE APPLICABLE
PRODUCT. NO ADDITIONAL ALLOWANCE SHALL BE MADE FOR THE LABOR OR
EXPENSE OF REPAIRING OR REPLACING PRODUCTS OR WORKMANSHIP OR
DAMAGE RESULTING FROM THE SAME OTHER THAN THAT PROVIDED IN THE FLAT
RATE LABOR SCHEDULE OUTLINED IN EXHIBIT A. EXCEPT AS EXPRESSLY SET
FORTH HEREIN, ALL PRODUCTS AND/OR PARTS PROVIDED BY HEXAGON AGILITY®
ARE PROVIDED “AS IS,” “WHERE IS” AND “WITH ALL FAULTS.” NO PERSON,
INCLUDING SALESPERSONS, DEALERS, OR FACTORY REPRESENTATIVES OF
HEXAGON AGILITY®, IS AUTHORIZED TO MAKE ANY REPRESENTATION OR
WARRANTY CONCERNING HEXAGON AGILITY® PRODUCTS EXCEPT TO REFER
PURCHASERS TO THIS LIMITED WARRANTY. HEXAGON AGILITY® MAKES NO
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

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Limitations & Exclusions
In addition to the limitations described above, items specifically not covered include but are
not limited to:
 Maintenance Items outlined in the maintenance schedule such as filters, any other
components listed as maintenance items. Failure to properly maintain these
components may lead to extensive damage of the fuel system thus voiding warranty
coverage.
 Loss of use and incidental consequential expenses, including but not limited to
commercial loss, loss of commercial fares, driver time or pay, lease or rental of
substitute vehicle, storage, lodging, meals, telephone calls and other travel costs.
 Wear, wear-out and consumption. This warranty shall not apply to any parts or
components which must be repaired, replaced or adjusted during the Warranty Period
that are due to wear, wear-out or consumption, including but not limited to filters,
lubricants, fluids, bushings, isolators. Wear not only includes friction-type wear but can
also include environmental deterioration including but not limited to surface corrosion
on lines/clamps and UV or chemical degradation of cylinder coatings.
 Any product failure by any of the following: improper handling, use or operation,
misapplication, negligence, neglect, corrosion, heat, fire, acts of nature, improper
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maintenance, lack of reasonable and scheduled maintenance, or installations, repairs,
misuse and/or abuse, including but not limited to excessive operation on unpaved, unmaintained roads, operation on cross-country trails or off-road conditions, collision, fire,
vandalism, explosion, objects striking the vehicle, theft, freezing, riot, flood.
 Vehicle modifications or equipment installations performed without the written approval
of Hexagon Agility® to the extent the modifications or equipment installations adversely
affect other vehicle components or performance, Hexagon Agility® shall not accept any
product liability or claims under the terms of the limited warranty. These claims become
the sole responsibility of the company performing the modifications and/or installations.
 Transportation expenses to deliver the vehicle to a Hexagon Agility® authorized service
provider or nearest vehicle OEM repair facility, including but not limited to fuel, driver
time/pay, mileage and towing.
 Repairs to parts or components which have been previously replaced with parts not
obtained from Hexagon Agility® or failures caused by non-Hexagon Agility® parts or
components. Rework of repairs not performed by or approved by an Hexagon Agility®
or OEM dealer. Defective products shall not be returned to Hexagon Agility® without its
written authorization.

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 Excessive labor hours, premium labor costs, overtime labor costs, local taxes, shop
fees. This limited warranty covers reasonable labor to perform the repair as outlined in
the standard repair time guide.
 Fuel used (though process of venting to atmosphere) either during repair of fuel system
components or through normal consumption or extensive road testing.
 Damage resulting from the use of improper or contaminated fluids, including but not
limited to fuels, lubricants and coolant. Damage caused by using fluids that do not meet
Hexagon Agility® minimum recommendations. Damage caused by the lack of fluids
and/or improper fluid maintenance.
 Overloading the vehicle above the maximum vehicle GVW and design intent operating
conditions.
Hexagon Agility® reserves the right to make changes in design and changes or
improvements upon its products without imposing any obligations upon itself to install the
same upon products theretofore manufactured. Any suit alleging a breach of this limited
warranty or of any other alleged warranty, including any claim for rescission or revocation
of acceptance, must be filed within one year of breach.

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FCCC MT-45 MT-55 CNG FUEL SYSTEM
P80 - P100 - P120 USER MANUAL

USM.0004 Ver. 1.0
April 4, 2022
Hexagon Agility Inc. Copyright © 2022. All Rights Reserved.