CNG High Pressure Hose
Inspection and Maintenance
ENP-730
February 12, 2020

Copyright ©2020. Agility® Fuel Solutions. All Rights Reserved.

Table of Contents
1. Introduction ............................................................................................................................... 3
1.1. Warning Statements Used in this Bulletin .............................................................................. 3
2. Affected vehicles ....................................................................................................................... 4
3. Tools and Materials ................................................................................................................... 4
4.1. Motion Industries hose – stainless steel braid ....................................................................... 5
4.2. Titeflex hose – stainless steel braid ....................................................................................... 6
4.3. Parker Parflex® 5CNG – fiber reinforced hose ....................................................................... 7
4.4. Swagelok® NG Series – fiber reinforced hose ....................................................................... 8
5. High Pressure CNG Hose Inspection Interval ........................................................................... 9
5.1. Inspection Procedure for All Hose Types ............................................................................... 9
6. Warranty Information............................................................................................................... 11
7. Support, Service or Parts ........................................................................................................ 11
8. Proprietary Statement ............................................................................................................. 12
9. Trademark Notice .................................................................................................................... 12

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1. Introduction
High pressure, flexible CNG fuel hoses can become compromised if exposed to corrosive
chemicals such as road de-icing products, excessive heat or if hoses are altered or moved
during or following a repair. Fuel hoses are also vulnerable to damage from vibration and
subsequent wear.
Agility® Fuel Solutions (Agility®) has established additional high pressure compressed natural
gas (CNG) hose inspection criteria and revised inspection and maintenance intervals.

1.1. Warning Statements Used in this Bulletin

Personal injury or death may occur if procedures are not followed.

Damage to equipment, fuel system or vehicle is possible if instructions are not followed.

Best practices or hints to help an operation or procedure go smoothly.

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2. Affected vehicles
All vehicles equipped with Agility® CNG fuel systems utilizing high pressure CNG fuel hoses.

3. Tools and Materials
To properly inspect high pressure CNG hoses, it will be helpful to have the following tools and
basic supplies on hand:

Item

Function

spray bottle
mild soap and water
soft bristle brush

Clean hoses and heat sleeves

shop rags
flashlight

Illuminate tight spaces

mirror

If necessary: Aid visual inspection

camera

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side cutters

Remove any zip ties securing heat sleeve

Swagelok Snoop®

Leak detection

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4. High Pressure CNG Hose Identification
Agility® CNG fuel systems may include high pressure hoses approved for CNG use
manufactured by several suppliers including Motion Industries, Titeflex, Parker, and Swagelok.

4.1. Motion Industries hose – stainless steel braid
Motion Industry high pressure CNG hoses are electrically conductive and coated with a
thermoplastic outer jacket. A typical high pressure CNG hose manufactured by Motion Industries
(Figure 1) may be identified by the following characteristics:
▪
▪
▪

Exposed stainless steel braid between outer jacket and collet
Indentations on collet crimp area
Metal ID tag with manufacturing and date code. Figure 1

3

4

1

5

2
Figure 1. Motion Industries flexible CNG fuel hose. Note longitudinal crimp marks (1) on
collet (2), unmarked plastic cover (jacket) (3), exposed stainless steel braid (4),
tube stub (5).

Figure 2. Motion Industries CNG hose metal ID tag includes date of manufacture
(circled).

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4.2. Titeflex hose – stainless steel braid
Titeflex high pressure CNG hoses consist of an electrically conductive PTFE inner core with a
DuPont Hytrel® thermoplastic outer jacket, and are temperature rated from -40F to 250F
(-54C to 121C). Titeflex hoses (Figures 3 and 4) typically possess the following distinguishing
features:
▪
▪
▪

Exposed stainless steel braid between outer jacket and collet
Plastic coated paper tag (may or may not be present)F
Titeflex marking and information specific to hose properties and fuel type on jacket

1

3

4

2

5

Figure 3. Titeflex flexible CNG fuel hose. Notice collet style (2) and crimp marks, the
plastic cover (jacket) (1) with markings (3) and exposed metal braid (4). A swaged
compression fitting (5) is attached to this example.

Figure 4. Left: Titeflex plastic coated paper tag may or may not be present.
Right: Titeflex hose outer jacket is imprinted with “TITEFLEX” branding, date of
manufacture (circled), and maximum pressure and temperature range ratings. NOTE:
Hose sample shown for illustration purposes; markings will vary with application.

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4.3. Parker Parflex® 5CNG – fiber reinforced hose
Parker Parflex® 5CNG reinforced nylon hoses do not have a stainless steel braid and may be
identified partially by the red polyurethane cover. Parflex hoses are electrically conductive and
temperature rated from -40F to 180F (-40C to 82C). Figures 5 and 6

1

2

3

Figure 5. Parker Parflex 5CNG fiber reinforced nylon CNG hoses feature a crimped
collet (1), and red plastic outer jacket (3). NOTE: Coiled spring strain relief (2) may not
be present in all applications.)

2
Figure 6. Left: Parflex 5CNG hose metal ID tag includes a plant code, manufacturing
location, and manufacturing date code (not visible).
Right: Red Parflex 5CNG outer jacket is marked “ELECTRICALLY CONDUCTIVE” along
with fuel type, and hose ratings.
Parker recommends visual inspection of hose assemblies on at least a monthly basis. Refer to
Parker Safety Guide, Parker Publication No. 4400-B.1, for more information.

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4.4. Swagelok® NG Series – fiber reinforced hose
Swagelok NG Series hoses do not have a stainless steel braid and may be identified partially
by a perforated polyurethane cover. Nylon Swagelok NG hoses feature fiber reinforcement, are
electrically conductive, and are temperature rated from -40F to 150F (-40C to 65C). Figures
7 and 8

1
3

2
Figure 7. Swagelok NG Series hoses feature crimped collets (1), perforated
polyurethane outer jacket (2), stainless steel ends (3).

Figure 8. Left: Swagelok NG Series hose outer jacket marked “SWAGELOK®” with size
and pressure rating and “ELECTRICALLY CONDUCTIVE”.
Right: Swagelok hose decal includes date of manufacture (DOM) (circled).

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5. High Pressure CNG Hose Inspection Interval
Agility® recommends the following inspection intervals for high pressure CNG hoses:
Monthly
OR
Every 200 hours.

5.1. Inspection Procedure for All Hose Types
Regardless of hose type or manufacturer, use the following inspection procedure:
1. Clean hose ends and fittings with mild soap and water; if applicable: use a soft bristled
brush to expose hose braid.
2. If hose end is covered by protective loom or fire sleeve, the sleeve may be temporarily
moved to expose the hose for inspection. Figure 9. Inspect the entire length of hose and
sleeve: if there is any damage to the sleeve, remove sleeve and inspect the hose
underneath at the damaged area. Replace hose immediately if any damage to the hose is
present.

1

2

3

4

5

Figure 9. If hose is covered with a fire sleeve (1) or split loom, remove sleeve or loom to
enable inspection of hose cover (2), braid (3), collet (4) and fitting (5). Always inspect
fire sleeve (1) or slip loom for damage.
3. Inspect hose routing by verifying there is no potential for rubbing or strain. Verify that hoses
do not contact any metal parts, electrical parts, battery cables, hydraulic hoses, etc.
4. Confirm hoses are routed in accordance with minimum distances to heat sources and, if
applicable, shielded.

Application

Minimum distance to
heat source

Heat shielding*
required?

2-in. (50.8mm)

Yes

8-in. (203.2mm)

No

Hoses**
*Heat shielding shall be reflective metal shielding.
**Fire sleeve required in engine compartment or near exhaust.

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Heat shields must be undamaged and firmly in place. Replace shields or fasteners if
missing or damaged.
Verify any additional protection devices—heat sleeve, tubing or other outer wraps—
are in place and in good condition and do not show signs of abrasion or wear.
5. Confirm mounting clips are present and properly installed.

Verify hose support clips are in place. Replace clipping hardware with identical or
better UV resistant materials.
6. For metal braided hose:
A. Inspect hose for date of manufacture (DOM). Refer to Section 4 above. For hoses
covered in fire sleeve or split loom, remove a section of the sleeve to verify date of
manufacture. If DOM is five years or greater, replace the hose assembly immediately.
B. Inspect for any signs of damage, including, but not limited to broken wire braid strands,
corrosion, kinks, cuts, abrasion, heat, chemical attack, etc.
C. Replace hose immediately if any damage is present, or every 5 years, whichever comes
first.
D. Use DOM on the hose to establish 5 year replacement date.

Neglecting to replace hoses at recommended intervals may lead to sudden hose
failure.
E. Check for leaks from hose or fittings. Refer to Section 6 below.

Any of the above conditions require immediate shut down and replacement of the
hose assembly. Refer to Section 7 below.
7. For fiber reinforced hose:
A. Inspect for any signs of damage, including, but not limited to cracks, abrasions, cuts,
kinks, bulges, blisters, heat damage, chemical attack, etc.
B. Check for leaks from hose or fittings. Refer to Section 6 below.

Any of the above conditions require immediate shut down and replacement of the
hose assembly. Refer to Section 7 below.
C. Replace hose immediately if any damage is present. There is no replacement schedule
for fiber-reinforced hoses.

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6. Warranty Information
This procedure is part of normal scheduled maintenance and not subject to warranty coverage.

7. Support, Service or Parts
Fuel system in- or out- of warranty product support may be obtained by calling Agility Fuel
Solutions Customer Care or via email.

Customer Care
+1 855 500 2445 (toll-free, U.S. and Canada)
+1 949 267-7745
Support
[email protected]
Parts Orders
[email protected]
When calling or emailing, please provide your name, phone number, email address, and
complete vehicle information: VIN, year, make, model, mileage, unit number vehicle owner, and
current vehicle location. A service advisor will contact you to arrange vehicle repair or ship a part.

Agility Fuel Solutions
3335 Susan Street, Suite 100
Costa Mesa, CA 92626
www.agilityfuelsolutions.com

A. All replacement parts must adhere to standards and ratings specified by Agility®.
Using any part not approved by Agility® is not recommended and may compromise
the integrity and safety of the system.
B. Do not remove components from original packaging until necessary. Any
components to be reinstalled must be thoroughly cleaned, inspected and stored in a
satisfactory manner until reinstallation.

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8. Proprietary Statement
The information provided within this document is proprietary and confidential. All prior versions,
including updates and revisions forwarded separately, are proprietary. The information provided
by Agility® to its customers and clients is solely for the use of those customers and clients. No
portion of this publication may be reproduced or distributed without express written consent of
Agility®. Agility® reserves the right to utilize the intellectual property contained within this
publication as content for any other publication produced by Agility®.

9. Trademark Notice
Agility® is a registered trademark of Agility® Fuel Solutions. Trademarks of other manufacturers
are the property of their respective companies.

Revision
--

ENP-730

Description
Initial Release

Author

Approved By

Date

C.Grasso

Management Team

2/12//2020

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