Bulletin Number:

SB-21-347

Release Date:

January 26, 2021

Distribution:

Heil Dealers, Heil Customers, Heil Technical Services, Heil Customer Care

Subject:

DuraPack® Python®: Pump-to-Valve 4-Wire Spiral Hydraulic Hoses
Standardization

NOTE: READ THIS BULLETIN IN ITS ENTIRETY BEFORE BEGINNING ANY REPAIR WORK.
Starting August 1, 2020, to ensure the highest hydraulic hose reliability, 4-wire spiral hydraulic hoses
became standard in the locations identified below on all DuraPack® Python® units.
To achieve this change, the following 2-wire braided hydraulic hoses (Parker 387ST-16) have been replaced
with 4-wire spiral hoses (Parker 722ST-16 or equivalent) as applicable:
(1) For units WITHOUT the Dual High-Pressure Filter option (Figure 1 and Figure 3):
(a) Pump P1 to lift valve: one (1) to two (2) hoses
(b) Pump P2 to flow combining tee: one (1) to two (2) hoses
(c) Flow combining tee to main body control valve: one (1) hose
(2) For units WITH the Dual High-Pressure Filter option (Figure 2 and Figure 4):
(a) Pump P1 to first high-pressure filter: one (1) hose
(b) First high-pressure filter to lift valve: one (1) hose (NOTE: changed in production to 4-wire hose
in February 2019)
(c) Pump P2 to second high-pressure filter: one (1) hose
(d) Second high-pressure filter to flow combining tee: one (1) hose (NOTE: changed in production
to 4-wire hose in August 2018)
(e) Flow combining tee to main body control valve: one (1) hose
To address units in the field, Heil Environmental agrees to provide warranty replacement of these OEM
installed hoses on the units listed in the Products Affected section when Hose Specification/Installation
Requirements from Section 3 of this Service Bulletin are followed. ONLY replace these hydraulic hoses if they
are 2-wire braided hydraulic hoses (Parker 387ST-16). Refer to Figures 1-4 on the next two pages.
Additionally, this Service Bulletin outlines the procedure to inspect all hose support clamps for proper
installation and perform Hydraulic System tasks as outlined in the Heil Service Manual Body Preventive
Maintenance Chart.

Copyright 2021, Heil Environmental

Page 1 of 9

FRONT MOUNT
PUMP

FLOW COMBINING TEE
TO MAIN BODY
CONTROL VALVE
PUMP P1 TO
LIFT VALVE:
2 HOSES

PUMP P2 TO
FLOW COMBINING
TEE: 2 HOSES

Figure 1. Units WITHOUT Dual High-Pressure Filter and WITH Front Mount Pump: Hose Configuration

FIRST HIGH-PRESSURE
FILTER TO LIFT VALVE

PUMP P1 TO
FIRST FILTER

SECOND HIGH-PRESSURE
FILTER TO FLOW
COMBINING TEE
FLOW COMBINING TEE
TO MAIN BODY
CONTROL VALVE

FRONT MOUNT
PUMP
PUMP P2 TO
SECOND FILTER

Figure 2. Units WITH Dual High-Pressure Filter and WITH Front Mount Pump: Hose Configuration
Copyright 2021, Heil Environmental

Page 2 of 9

FLOW COMBINING
TEE TO MAIN BODY
CONTROL VALVE

HOSE CONFIGURATION AND
ROUTING MAY VARY WITH
PTO CONFIGURATION AND
UNIT MANUFACTURE DATE

PUMP P2 TO
FLOW
COMBINING TEE
PUMP P1 TO
LIFT VALVE

PTO MOUNTED
PUMP

Figure 3. Units WITHOUT Dual High-Pressure Filter and WITH PTO Mounted Pump: Hose
Configuration
HOSE CONFIGURATION AND
ROUTING MAY VARY WITH
PTO CONFIGURATION AND
UNIT MANUFACTURE DATE
FIRST HIGH-PRESSURE
FILTER TO LIFT VALVE

PUMP P1 TO
FIRST

PTO MOUNTED
PUMP

SECOND HIGH-PRESSURE
FILTER TO FLOW
COMBINING TEE

FLOW COMBINING TEE
TO MAIN BODY
CONTROL VALVE

PUMP P2 TO
SECOND FILTER

Figure 4. Units WITH Dual High-Pressure Filter and WITH PTO Mounted Pump: Hose Configuration
Copyright 2021, Heil Environmental

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1.

PLANNING INFORMATION
A. Products Affected
This Service Bulletin applies to DuraPack® Python® units manufactured between January 1, 2017
and July 31, 2020, excluding Waste Management units.

B.

Compliance
Each Dealer must perform these tasks as outlined in this Service Bulletin for each unit identified
above in the Products Affected section no later than March 19, 2021. The tasks outlined in this
Service Bulletin must be performed by a qualified technician.

C. Manpower
The labor effort required to accomplish the tasks in this Service Bulletin is shown in Table 1.
Table 1. Manpower

TASK

MAN HOURS REQUIRED

Replace high-pressure hydraulic hoses as described in this Service Bulletin

0.5 per replaced hose

D. Tools, Materials and Parts Needed
The tools and parts necessary to perform the rework are outlined in Table 2 and Table 3.
Item
Personal Protective Equipment
Wrench Set
Torque Wrench
Bucket

Table 2. Tools and Materials
Part Number
Commercially available
Commercially available
Commercially available
Commercially available

Application
Safety protection as required by employer
To disconnect/connect hydraulic fittings
To properly tighten hydraulic fittings
To capture hydraulic fluid

Table 3. Parts

PART NUMBER

DESCRIPTION

MP6-FKFK-020,
MP6-FKFK-021,
MP6-FKFK-022,
through
MP6-FKFK-100

Hydraulic Hose, 4000 PSI
Minimum Working Pressure, 4Wire Spiral, 1”

N/A

Crimp Fitting, -16 (1”), Female 37
Degree, JIC, Straight Swivel
Clamp, 4-Wire Spiral Hydraulic
Hose, 1”

QTY PER
UNIT
3-5

SPECIAL INSTRUCTIONS
Hose part number varies with chassis
configuration. Heil part number ends in
hose length in inches.
Use Parker 722ST-16 or equivalent. See
Table 4.

036-1982-50380

Copyright 2021, Heil Environmental

4

Hose end crimp fittings are specific to
the brand and model of hose.

3

Page 4 of 9

Table 4. Replacement OEM Hose Brand and Model Equivalents
BRAND
Parker
Gates
Eaton / Aeroquip
Eaton / Weatherhead
Eaton / Weatherhead
Semperit
Kurt
Pirtek

2.

MODEL
722ST
EFG4K
GH493
H430
H471
FLEXLINE 4000
E-Z BEND 4SK
100CS3

PREPARING THE UNIT AND WORK AREA

Prior to performing Lock-Out/Tag-Out, make sure to LOWER the arms and forks FULLY DOWN to
the ground or RAISE the arms FULLY UP against the arm stops.
Be certain that all hydraulic pressure has been fully relieved before beginning any hydraulic
rework.
To relief the hydraulic pressure in the system:
(1) When there are in-cab controls, turn the ignition switch to ON then:
(a) Move the switches of the hydraulic controls. This relieves the pressure in the cylinders.
(b) Turn the ignition switch to OFF.
(c) When there are no in-cab controls, move the outside control levers to relieve the pressure
in the cylinders.
Make sure that the unit is in Lock-Out/Tag-Out mode before performing re-work. Refer to and follow
your company’s Lock-Out/Tag-Out policies and procedures. At a minimum, refer to and follow the LockOut/Tag-Out procedure found in your Heil Service Manual. Always wear appropriate Personal Protective
Equipment as required by your employer (but to always include at a minimum, safety glasses and OSHA
approved hard-toed boots) when repairing a unit or performing scheduled maintenance on a unit. Clear
the work area around the unit of all unnecessary people and equipment.

Copyright 2021, Heil Environmental

Page 5 of 9

3.

CORRECTIVE ACTIONS

With the unit prepared as described in step 2 of this Service Bulletin, in Lock-Out/Tag-Out mode,
carefully follow the steps below. Repeat procedure for all affected high-pressure hoses.

A.

Inspect for Affected High-Pressure Hydraulic Hoses
Visually inspect the high-pressure hoses listed below to determine if they are 2-wire braided
hydraulic hoses (Parker 387ST-16). ONLY 2-wire braided hydraulic hoses (Parker 387ST-16)
should be replaced with 4-wire spiral hoses (Parker 722ST-16 or equivalent; See Table 4). The
Parker hose model number will be clearly printed on the outside of the hose.
(1) For units WITHOUT the Dual High-Pressure Filter option, inspect:
(a) Pump P1 to lift valve: one (1) to two (2) hoses
(b) Pump P2 to flow combining tee: one (1) to two (2) hoses
(c) Flow combining tee to main body control valve: one (1) hose
(2) For units WITH the Dual High-Pressure Filter option, inspect:
(a) Pump P1 to first high-pressure filter: one (1) hose
(b) First high-pressure filter to lift valve: one (1) hose (NOTE: changed in production to 4-wire
hose in February 2019)
(c) Pump P2 to second high-pressure filter: one (1) hose
(d) Second high-pressure filter to flow combining tee: one (1) hose (NOTE: changed in
production to 4-wire hose in August 2018)
(e) Flow combining tee to main body control valve: one (1) hose

B.

Replace ONLY 2-Wire Braided Hydraulic High-Pressure Hydraulic Hoses
Refer to Table 3 for Heil part numbers and Table 4 for the Parker replacement hose and nonParker hose equivalents.
(1) Identify the hydraulic hoses to be replaced. Refer to Figures 1-4.
NOTE: For units equipped with the Dual High-Pressure Filter option, the hose from the
first high-pressure filter to the lift valve and the hose from the second dual highpressure filter to the flow combining tee may already be 4-Wire Spiral, and therefore
would not need to be replaced. Check the hose model number printed on the hose.
(2) Detach the hydraulic fittings and drain remaining oil from the old hose into the container.
(3) Procure new 1” diameter high-pressure hoses (Parker 722ST-16 or equivalent) with new
fittings that meet the requirements below. Some unit configurations may require different length
hoses than the hose that is being replaced in order to achieve the following installation
requirements, however the hose length of the hose being replaced can be used as a baseline
for determining the replacement hose length.

Copyright 2021, Heil Environmental

Page 6 of 9

Hose Specification/Installation Requirements:
(a) The required minimum Bend Radius specification of the replacement hose material is 6”
or less.
(b) Length of the replacement hose must allow the installed hose Bend Radius to be 6” or
more.
(c) Installation of the replacement hose must allow for a straight section of hose adjacent to
the crimp fitting to be a minimum of twice the Outside Diameter (OD) of the hose. For a
Heil supplied hose for this application this is a minimum of 2.75”.
(d) The hose length must be made so that the hose assembly has enough length to allow for
changes in length to occur when the hose is pressured and for the system components to
operate without violating the installation requirements.
(e) The replacement hose must have an integrated Abrasion Resistant Outer Layer. All
replacement hoses are to be of the 4-wire spiral construction and have a minimum of
4000 PSI Working Pressure rating.
(4) Install the new hydraulic hoses. Use a backup wrench to ensure that the hose does not twist
while tightening the fittings. Torque fittings to 130 FT-LBS.

C. Test for Hydraulic Fluid Leaks
(1) Take the unit out of Lock-Out/Tag-Out Mode.
(2) Operate all unit functions. Then check for leaks. If there are leaks, loosen and re-torque the
hydraulic fittings that are leaking and then check again for leaks. When there are no leaks,
check hydraulic oil level and add oil if needed. Contact Technical Services if leaks continue.
(3)

When there are no leaks, check hydraulic oil level and add new oil if needed. Never reuse
drained oil.

D. Inspect all Hydraulic Hose Support Clamps
Hydraulic tube clamps should never be used on hydraulic hoses. Over time, these types of clamps
will rub through the hose covering and potentially cause hose failure.
(1) Inspect all hose clamps. There must be no daylight coming through between the hose and
clamp, as shown in Figure 5. The clamps must be tight and secure around the hoses, as
shown in Figure 6.

Figure 5. INCORRECT Use of Tube Clamps for
Hoses
Copyright 2021, Heil Environmental

Figure 6. CORRECT Use of Hose Clamps for
Hoses
Page 7 of 9

(2) Replace any tube clamps used for hoses with appropriately sized hose clamps. Refer to Table 5.
Table 5. Hose Support Clamp Part Number for Parker 722ST-16

SINGLE HOSE SUPPORT CLAMP FOR PARKER ABRASION RESISTANT HOSE
WITHOUT FIBER GUARD
HOSE
WORKING
PRESSURE

HOSE
CONSTRUCTION

4000 PSI

4-WIRE SPIRAL

E.

PARKER
HOSE
SERIES

PARKER
HOSE
SIZE

722ST

16

HOSE
OUTSIDE
DIAMETER
INCH

1.49

MM

37.8

HEIL PART
CLAMP NUMBER

CLAMP
BORE
(MM)

036-1982-50380

38.0

Body Hydraulics Preventive Maintenance
Following the Body Preventive Maintenance schedule found in Heil Service Manuals, perform the
Hydraulic System tasks below.
(1) Daily (8 Hours)
(a) Check oil level – add if necessary.
(2) Weekly (40 Hours)
(a) Check cylinders, pump, hoses, tubes, fittings, and adapters for leaks.
(b) Check hoses for cracks, crushes, and cover blisters. Repair or replace if necessary with
genuine Heil parts.
(c) Any replacement hose should be the same size and pressure rating as listed on the
original OEM hose.
(d) Check control valve seals for leaks. Repair or replace if necessary.
(3) Every Six Months (1000 Hours)
(a) Replace filters after first 30 days of operation, then every 6 months or 1000 hours of
operation OR when filter bypass light is ON.
(b) Replace tank breather filter every time you replace filter element.
(4) Yearly (2000 Hours)
(a) Drain, flush, and refill.

(b) Change filter elements.
(c) Change oil when oil sample shows to change oil.

Copyright 2021, Heil Environmental

Page 8 of 9

To obtain reimbursement from Heil for the hydraulic hoses (with fittings) and any re-work as a result of implementing this
Service Bulletin, submit one completed Request For Credit (RFC) for each unit re-worked. Heil Dealers and Service
Centers must file claims electronically using Heil’s online warranty system. Labor will be reimbursed one-half (0.5) hour
per qualified and replaced high-pressure hydraulic hose per re-worked unit on affected units listed in this Service Bulletin.
Heil reserves the right to request the return of any replaced hoses for our inspection to review any
reimbursement claim. All re-work must be completed by March 19, 2021.

If you have any questions regarding the information detailed in this Bulletin, please contact Heil Technical
Service at 866.310.4345.

Heil Environmental Service Bulletin procedures are intended for use by professional technicians, NOT a “do-it-yourselfer.” They are
written to inform experienced technicians of conditions that may occur on some units, or to provide information that could assist in the
proper servicing of a unit. Properly trained technicians have access to and are familiar with the applicable Heil Operation Manual
and Heil Parts and Service Manuals and have the equipment, tools, safety training, and know-how to do a job properly and safely. If a
condition is described, DO NOT assume that the Bulletin instructions apply to your unit, or that your unit will have that condition. See
your Heil Dealer to determine whether your unit may benefit from the information in this Service Bulletin.
This entire bulletin (and any attachments) is confidential and only for the intended recipient(s). Use or distribution by any unintended
recipient is prohibited. If you have received this bulletin in error, delete this entire communication, and notify the sender you have done
so.
Copyright 2021, Heil Environmental

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