Mec 3072RT User manual

SERVICE AND PARTS MANUAL
Part # 91220 R1
March 2008
3072RT / 3772RT
3772RT HD
Serial Number Range
3072RT: 9201000 - Present
3772RT / 3772RT HD: 9301000 - Present
1775ParkStreet,Suite77
Selma,California93662
Phone:[phone]Fax:[phone]
1775ParkStreet, Suite77
Selma,California93662
Phone:[phone]Fax:[phone]
ART_2497

1775 Park Street, Suite 77 • Selma, CA 93662 USA
Ph: 1-800-387-4575 • 559-891-2488 • Fax: [phone]
E-mail:[e-mail] • Web:www.mecawp.com
Aerial Platform Sales Corp.
Service Section 2
Update illustration: Deutsch Connectors
Add illustrations and update text: Continuity Checks
Page 2-3
Page 2-11
Revision History:
March 2008
Service Section 4
Update Step 3:Setting Counterbalance ValvesPage 4-11
Service Section 5
Update text: Hydraulic Schematic - bold table heads
Update illustration: Hydraulic Schematic
Update illustration: Outrigger Electric Schematic
Update illustration: Generator Option Schematic
Page 5-2
Page 5-3
Page 5-15
Page 5-16
Parts Section 1
Update illustration: Base Control Box
Update parts list to identify key switch and related components
Page 1-8
Page 1-9
Parts Section 4
Update illustration: Rear Axle Assembly
Update parts list to identify valve shields and related components
Page 4-2
Page 4-3
Parts Section 6
Update illustration: Base Assembly
Update parts list to identify Power to Platform Bracket
Update illustration: Control Module
Update parts list to identify Hole Plug
Update illustration: Engine, Dual Fuel
Update illustration: Engine, Dual Fuel
Update parts list to identify new part numbers
Update illustration: Engine, Diesel
Update parts list to identify new part numbers
Update illustration: Engine, Diesel
Update parts list to identify new part numbers
New illustration: Harnesses
Update parts list to identify new part numbers
Update illustration: Outrigger Install
Update parts list to identify Power to Platform Bracket
New Illustration: Generator Option, Dual Fuel
Update parts list to identify new part numbers
New Illustration: Generator Option, Diesel
Update parts list to identify new part numbers
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Reason for update
Pages
Parts Section 7
Update illustration: 3072RT Sides
Update parts list
Update illustration: 3072RT Ends
Update parts list
Update illustration: 3772RT / 3772RT HD Sides
Update parts list
Update illustration: 3772RT / 3772RT HD Ends
Update parts list
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Introduction
Update Specifications Table
Update Illustration
Page V
Page VI

Table of Contents
"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page i
Service Sections
INTRODUCTION ............................................................................................... I
General Safety Tips ............................................................................................... III
Hydraulic System ............................................................................................... IV
Electrical System................................................................................................ IV
Total System ....................................................................................................... IV
Machine Specifications .......................................................................................... V
Primary Machine Components ............................................................................ VII
LUBRICATION ...................................................................................................... VIII
SECTION 1:
HYDRAULIC SYSTEM ............................................................................. 1-1
Hydraulic System - General ................................................................................ 1-2
Hydraulic Fluid ..................................................................................................... 1-3
Hydraulic Fluid Reservoir ................................................................................... 1-6
Hydraulic Pump ................................................................................................... 1-7
Wheel Drive .......................................................................................................... 1-7
Parking Brake and Towing Circuit .................................................................... 1-14
Emergency Systems And Procedures ............................................................. 1-15
Steering Circuit .................................................................................................. 1-16
Platform Lift Circuit ........................................................................................... 1-18
Optional Outriggers ........................................................................................... 1-20
Cylinder Repair .................................................................................................. 1-21
Hydraulic Manifold............................................................................................. 1-24

Table of Contents
March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page ii
SECTION 2:
ELECTRICAL SYSTEM ........................................................................... 2-1
Electrical System - General ................................................................................ 2-2
Deutsch Connectors............................................................................................ 2-3
Battery .................................................................................................................. 2-4
Battery Preventative Maintenance:................................................................... 2-5
Battery Replacement........................................................................................ 2-6
Alarms and Switches .......................................................................................... 2-7
Tilt Alarm .......................................................................................................... 2-8
Relays .............................................................................................................. 2-9
Limit Switch ....................................................................................................... 2-10
Optional Outriggers Switches .......................................................................... 2-10
Continuity Checks ............................................................................................. 2-11
SECTION 3:
MECHANICAL COMPONENTS ............................................................... 3-1
Torque Specifications ......................................................................................... 3-2
Mechanical Components .................................................................................... 3-3
Base/ Undercarriage ........................................................................................ 3-3
Raising the Machine ......................................................................................... 3-3
Tires ................................................................................................................. 3-4
Drive Motors ..................................................................................................... 3-5
Steer Cylinder .................................................................................................. 3-6
Hoses and Cables ............................................................................................ 3-7
Platform Removal ............................................................................................. 3-7
Lift Cylinder Removal and Installation .............................................................. 3-8
Scissor Beam Assembly................................................................................... 3-8
Engine Maintenance ............................................................................................ 3-9
Diesel Engine ................................................................................................... 3-9
Gasoline and Dual Fuel Engine...................................................................... 3-12
Outrigger Function ............................................................................................ 3-14
Outrigger Calibration ...................................................................................... 3-15
GP106 Outrigger Control Module Troubleshooting ......................................... 3-17
Outrigger Module GP106 LED Flash Codes .................................................. 3-18

Table of Contents
"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page iii
SECTION 4:
TROUBLESHOOTING ............................................................................. 4-1
Troubleshooting ................................................................................................... 4-3
General Troubleshooting Tips ........................................................................... 4-3
Common Causes of Hydraulic System Malfunctions:....................................... 4-3
Hydraulic Pressure Adjustment Procedures..................................................... 4-9
Proportional Speed Adjustment ....................................................................... 4-12
Controls and Switches ...................................................................................... 4-14
SECTION 5:
SCHEMATICS ..........................................................................................5-1
Hydraulic Schematic ........................................................................................... 5-2
Main Hydraulic Manifold ................................................................................... 5-4
Optional Outriggers Hydraulic Manifold ............................................................ 5-5
Electric Schematics ............................................................................................. 5-6
Circuit Board .................................................................................................... 5-8
Controls .......................................................................................................... 5-10
Engine ............................................................................................................ 5-13
Optional Outriggers ........................................................................................ 5-15
Optional Generator ......................................................................................... 5-16

Table of Contents
March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page iv
Parts Sections
SECTION 1: CONTROL BOXES
SECTION 2: PLATFORM AND RAILS
SECTION 3: SCISSORS
SECTION 4: AXLES
SECTION 5: HYDRAULICS
SECTION 6: BASE
SECTION 7: DECALS

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page I
INTRODUCTION
This manual consists of Service and Parts illustrations sections.
The Service Section of this manual is designed to provide you, the customer, with the instructions
needed to properly maintain the MEC self-propelled scissors lift. When used in conjunction with
the illustrated parts section and the Operators Manual (provided separately), this manual will
assist you in making necessary adjustments, repairs, identifying, and ordering the correct re-
placement parts.
All parts represented here are manufactured and supplied in accordance with MEC’s quality
standards.
We recommend that you use Genuine MEC parts to insure proper OPERATION and reliable
PERFORMANCE.
To obtain maximum benefits from your MEC scissors lift, always follow the proper operating and
maintenance procedures. Only trained authorized personnel should be allowed to operate or
service this machine. Service personnel should read and study the Operator’s, Service and Parts
Manuals in order to gain a thorough understanding of the unit prior to making any repairs.
To help you recognize important safety information, we have identified warnings and instructions
that directly impact on safety with the following signals:
“DANGER” INDICATES AN IMMINENTLY HAZARDOUS SITUATION
WHICH, IF NOT AVOIDED, WILL RESULT IN DEATH OR SERIOUS
INJURY. THIS SIGNAL WORD IS LIMITED TO THE MOST EXTREME
SITUATIONS.
“WARNING” INDICATES A POTENTIALLY HAZARDOUS SITUATION
WHICH, IF NOT AVOIDED, COULD RESULT IN DEATH OR SERIOUS
INJURY.
“CAUTION” INDICATES A POTENTIALLY HAZARDOUS SITUATION
WHICH, IF NOT AVOIDED, MAY RESULT IN MINOR OR MODERATE
INJURY. IT MAY ALSO BE USED TO ALERT AGAINST UNSAFE
PRACTICES. “CAUTION” IS USED FOR PROPERTY-DAMAGE ONLY
ACCIDENTS.

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page II
NOTE: The best method to protect yourself and others from injury or death is to use
common sense. If you are unsure of any operation, don’t start until you are satis-
fied that it is safe to proceed and have discussed the situation with your supervi-
sor.
Service personnel and machine operators must understand and comply with all warnings and
instructional decals on the body of the machine, at the ground controls, and platform control
console.
MODIFICATIONS OF THIS MACHINE FROM THE ORIGINAL DESIGN
AND SPECIFICATIONS WITHOUT WRITTEN PERMISSION FROM
MEC ARE STRICTLY FORBIDDEN. A MODIFICATION MAY
COMPROMISE THE SAFETY OF THE MACHINE, SUBJECTING
OPERATOR(S) TO SERIOUS INJURY OR DEATH.
MEC’s policies and procedures demonstrate our commitment to Quality and our relentless ongo-
ing efforts towards Continuous Improvement, due to which product specifications are subject to
change without notice.
Any procedures not found within this manual must be evaluated by the individual to assure one-
self that they are “proper and safe.”
Your MEC Scissors Lift has been designed, built, and tested to provide many years of safe, de-
pendable service. Only trained, authorized personnel should be allowed to operate or service the
machine.
MEC, As Manufacturer, Has No Direct Control Over Machine Application And Operation. Proper
Safety Practices Are The Responsibility Of The User And All Operating Personnel.
If There Is A Question On Application And/Or Operation Contact:
Aerial Platform Sales Corp.
1775 Park Street, Suite 77 • Selma, CA 93662 USA
Ph: 1-800-387-4575 • 559-891-2488 • Fax: [phone]
www.mecawp.com

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page III
GENERAL SAFETY TIPS
Regular inspection and conscientious maintenance is the key to efficient economical operation of
your scissors lift. It will help to assure that your equipment will perform satisfactorily with a mini-
mum of service and repair.
The actual operating environment of the machine governs the inspection schedule. Correct lubri-
cation is an essential part of the preventative maintenance to minimize wear on working parts
and ensure against premature failure. By maintaining correct lubrication, the possibility of me-
chanical failure and resulting downtime is reduced to a minimum.
NEVER PERFORM SERVICE ON THE MACHINE (WITH THE
PLATFORM ELEVATED) WITHOUT FIRST BLOCKING THE BEAMS
(SCISSORS) ASSEMBLY IN PLACE USING THE MAINTENANCE
LOCK!
•Block scissors assembly using Maintenance Lock if
machine is in the elevated/extended position.
•Never leave hydraulic components or hoses open.
They must be protected from contamination (includ-
ing rain) at all times.
•Never open a hydraulic system when there are con-
taminants in the air.
•Always clean the surrounding area before opening
hydraulic systems.
•Use only recommended lubricants. Improper lubri-
cants or incompatible lubricants may be as harmful
as no lubrication.
•Watch for makeshift “fixes” which can jeopardize
safety as well as lead to more costly repair.
Maintenance Lock In Position
3072RT
3772RT

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page IV
Hydraulic System
HYDRAULIC FLUID UNDER PRESSURE CAN PENETRATE AND
BURN SKIN, DAMAGE EYES, AND MAY CAUSE SERIOUS INJURY,
BLINDNESS, AND EVEN DEATH.
CORRECT LEAKS IMMEDIATELY.
Hydraulicfluid leaks under pressure may not always be visible.
Check for pin hole leaks with a piece of cardboard, not your hand.
Electrical System
Prevent damage to battery and/or electrical system;
• Always disconnect the negative battery cable first.
• Always connect the positive battery cable first.
If contact is made between the positive side of the battery and a metal surface on the machine
when the negative cable is installed a spark will occur. This can cause damage to the electrical
system, battery explosion, and personal injury.
Total System
Engine coolant level must be checked only after engine has cooled.
If radiator cap is removed while the coolant is at normal operating
temperature, pressure within the coolant system will force hot liquid
out through the filler opening and possibly cause severe scalding.
Failure to perform preventive maintenance at recommended
intervals may result in the unit being operated with a defect that
could result in injury or death of the operator.
Immediately report to your supervisor any Defect or malfunction.
Any defect shall be repaired prior to continued use of the scissors
lift.
Inspection and maintenance should be performed by qualified
personnel familiar with the equipment.

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page V
WorkingHeight*
Platform Height
Platform Entry Height
Stowed Height
RailsFolded Down
RailsUp
Maximum Number of Occupants
Lift Capacity (Evenly Distributed)
Roll-out Deck Capacity
Platform Dimensions
With Roll-Out Deck Extended
With Roll-Out Deck Retracted
Deck Width
Guardrail Height
Toeboard Height
Roll-out Deck Length
Overall Length
Overall Width
Wheel Base
Wheel Track
TurningRadiusInside
Outside
Ground Clearance
Machine Weight** (Unloaded) (Approx.)
Drive System (Proportional)
Drive Speed (Platform Elevated)
Drive Speed (Platform Lowered)
Lift/Lower Speed (Approx.)
Gradeability
Ground Pressure/Wheel (Maximum)
Tire Size-Standard
12 Ply Foam-Filled (Option)
Tire Pressure, 12 Ply Pneumatic
Wheel Load
Wheel LugNut Torque
Hydraulic Pressure Main System
Lift System
Steer
Standard
Option
Hydraulic Fluid Capacity
Fuel Capacity
Power System – Voltage
Alternator (LightingCoil)
Engine Availability
Meetsrequirementsof ANSI A92.6-2006 Section 4.
*Working height adds6 feet (2 m) to platform height.
**Weight may increase with certain optionsor country standards.
3072RT 3772RT 3772RT HD
2 Wheel Drive Standard, 4 Wheel Drive Option
26.0-12.0-380 26.0-12.0-380 26.0-12.0-380
Kubota DF752E, 22 HP (16.4 kW), Dual Fuel, Liquid Cooled
Kubota D905E, 20 HP (14.9kW), Diesel, Liquid Cooled
36.0 ft*
30.0 ft
54 in
108.5 in
78.5 in
3
1,000 lb
400 lb
158 in
110 in
60 in
43.5 in
6.0 in
48 in
117.25 ft
72 in
86.0 in
60.5 in
73.25 in
14 ft 2.5 in
9.5 in
7,062 lb**
0 – 0.4 mph
0 – 4.0 mph
91 psi
60 psi 60 psi 60 psi
2,722 lb
75-85 ft/lb
2800 psi
2500 psi
1500 psi
23 GAL
15 GAL
12 Volts DC
40 Amp
26 sec / 28 sec 28 sec / 31 sec 28 sec / 31 sec
45% / 24.2° 40% / 21.5° 40% / 21.5°
Foam-Filled
11.14 m*
9.14 m
1.4 m
2.75 m
1.99 m
3
454 kg
181 kg
4.01 m
2.79 m
1.52 m
1.10 m
15.0 cm
1.22 m
2.98 m
1.83 m
2.18 m
1.54 m
1.86 m
4.33 m
24 cm
3203 kg**
0 –0.6 km/h
0 – 6.4 km/hr
6.4 kg/cm²
4.14 bar 4.14 bar 4.14 bar
1235 kg
102-115 Nm
193 bar
172 bar
103 bar
87 liters
57 liters
12 Volts DC
40 Amp
26 sec / 28 sec 28 sec / 31 sec 28 sec / 31 sec
45% / 24.2° 40% / 21.5° 40% / 21.5°
Foam-Filled
750 lb
400 lb
158 in
110 in
60 in
43.5 in
6.0 in
48 in
117.25 ft
72 in
86.0 in
60.5 in
73.25 in
14 ft 2.5 in
9.5 in
7,975 lb**
0 – 0.4 mph
0 – 4.0 mph
97 psi
2,921 lb
75-85 ft/lb
3000 psi
2500 psi
1500 psi
23 GAL
15 GAL
12 Volts DC
40 Amp
43 ft*
37 ft
61 in
105.75 in
74 in
3
Foam-Filled
340 kg
181 kg
4.01 m
2.79 m
1.52 m
1.10 m
15.0 cm
1.22 m
2.98 m
1.83 m
2.18 m
1.54 m
1.86 m
4.33 m
24 cm
3589 kg**
0 –0.6 km/h
0 – 6.4 km/hr
6.8 kg/cm²
1325 kg
102-115 Nm
207 bar
172 bar
103 bar
87 liters
57 liters
12 Volts DC
40 Amp
13.28 m*
11.28 m
1.5 m
2.62 m
1.88 m
3
Foam-Filled
1,000 lb
400 lb
158 in
110 in
60 in
43.5 in
6.0 in
48 in
140 in
73.25 in
86.0 in
60.5 in
73.25 in
14 ft 2.5 in
9.5 in
8,585 lb**
0 – 0.4 mph
0 – 4.0 mph
100 psi
2,996 lb
75-85 ft/lb
3000 psi
2500 psi
1500 psi
23 GAL
15 GAL
12 Volts DC
40 Amp
43 ft*
37 ft
61 in
105.75 in
74 in
3
Foam-Filled
454 kg
181 kg
4.01 m
2.79 m
1.52 m
1.10 m
15.0 cm
1.22 m
3.56 m
1.86 m
2.18 m
1.54 m
1.86 m
4.33 m
24 cm
3863 kg**
0 –0.6 km/h
0 – 6.4 km/hr
7.0 kg/cm²
1359 kg
102-115 Nm
207 bar
172 bar
103 bar
87 liters
57 liters
12 Volts DC
40 Amp
13.28 m*
11.28 m
1.5 m
2.62 m
1.88 m
3
Foam-Filled
MACHINE SPECIFICATIONS

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page VI
3072RT
3772RT HD
Front
Front
Platform Assembly
Rollout Deck
Lift Assembly
Lift Assembly
Power Module
Upper ControlsMaintenance
Lock
Maintenance
Lock
Control Module
Outrigger
Assembly
Liquid Propane
(Dual Fuel Option)
Liquid Propane
(Dual Fuel Option)

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page VII
Component Service Section Parts Section
Platform Assembly
UpperControls2 | 4 | 5 1 | 2
Deck and Rails32
ChainClosure2
Optional Gate 2
Rollout Deck 2
Control Terminal Strip 1
Horn (optional) 2 1
Lift Assembly
Beamsintro3
Maintenance Lock intro3
Lift Cylinders 1 | 3 | 4 | 5 3 | 5
Limit Switch 2 | 4 3
Base Assembly
Front Drive Motors intro | 1 | 3 | 4 | 5 4 | 5 | 6
R Drive Motors w/Brakesintro | 1 | 3 | 4 | 5 4 | 5 | 6
Steering Components1 | 3 3 | 5 | 6
Steering Components1 | 3 | 4 | 5 3 | 5 | 6
Wheels& Tiresintro | 3 6
Hubsintro6
Slide Block intro6
Emergency Lowering1
Hoses& Cables1 | 2 | 3 | 5 | 6
Outrigger(Option) 1 | 3 | 4 | 5 5 | 6
LPG (Option)36
Power Module
Engine 3 | 4 | 5 6
Hydraulic Pump 1 | 3 | 4 | 5 6
Hydraulic reservoirintro | 1 6
Hydraulic Filterintro | 1 6
Component Service Section Parts Section
Control Module
LowerControls2 | 3 | 4 | 5 1 | 6
Hydraulic Manifold 1 | 3 | 4 | 5 5 | 6
Parking Brake Release1
Emergency Lowering1
Fuel Tank6
Fuel Shutoff 6
Powerto Platform6
Tilt Sensor2 | 3 | 4 | 5 6
Battery & Disconnect 2 | 3 | 4 | 5 6
OutriggerManifold 1 | 3 | 4 | 5 5 | 6
OutriggerControl Module
(OutriggerOption)2|5 6
AC Generator(Option) 5 5 | 6
Relays
Platform Power2 | 4 | 5 1
Torque Speed 2 | 4 | 5 6
Throttle 2 | 4 | 5 6
Preheat 2 | 4 | 5 6
Outrigger(Option) 3 | 4 | 5 6
AC Generator(Option) 5 6
PRIMARY MACHINE COMPONENTS

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page VIII
FRONT REAR
3
5
4
Drain Plug
Zerk Fittings
Zerk Fittings
1
2
X72-Lube
LUBRICATION
SPECIFICATION FREQUENCYITEM
NO.
2
3
4
5
1 Hydraulic
Reservoir
Hydraulic
Filter
Front Hubs
Steering
Pivots
Slide Block
Fixed
Filter Element
Lithium N.L.G. #2 EP
Purge Old Grease
Lithium N.L.G. #2 EP
Purge Old Grease
Lithium N.L.G. #2 EP
Purge Old Grease
Fill To The Middle Of The Sight Gauge
With Platform In The Stowed Position.
Mobile 424. Do not substitute with
lower grade oils as pump damage
may result.
Change Every Six Months Or
500 Hours, Whichever Occurs
First For Normal Usage.
Change Every Three Months
Or 300 Hours, Whichever
Occurs First For Severe
Usage.
Monthly or Every 25 Hours,
Whichever Occurs First
Monthly or Every 25 Hours,
Whichever Occurs First
Monthly or Every 25 Hours,
Whichever Occurs First
Check Daily.
Change Yearly Or Every 1,000
Hours, Whichever Occurs First.

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page 1-1
SECTION 1:
HYDRAULIC
SYSTEM
SECTION 1:
HYDRAULIC SYSTEM .............................................................................. 1-1
Hydraulic System - General ........................................................................................................................... 1-2
Hydraulic Fluid ............................................................................................................................................... 1-3
Hydraulic Fluid Reservoir ............................................................................................................................... 1-6
Hydraulic Pump ............................................................................................................................................. 1-7
Wheel Drive ................................................................................................................................................... 1-7
Parking Brake and Towing Circuit ................................................................................................................ 1-14
Emergency Systems And Procedures ......................................................................................................... 1-15
Steering Circuit ............................................................................................................................................ 1-16
Platform Lift Circuit ....................................................................................................................................... 1-18
Optional Outriggers ...................................................................................................................................... 1-20
Cylinder Repair ............................................................................................................................................ 1-21
Hydraulic Manifold ....................................................................................................................................... 1-24

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page 1-2
HYDRAULIC SYSTEM - GENERAL
The hydraulic system is an open center, open- loop type. Generally in this type of system, hydrau-
lic fluid is provided by a variable displacement, pressure compensated, piston type pump which is
directly coupled to the engine. As the engine turns, the hydraulic pump drains oil from the reser-
voir and pumps this fluid to the valve packages.
If no function is selected to perform, the pump remains on standby and no fluid is pumped
through the manifold. Each function has a maximum pressure control limit set by pressure relief
valve.
Hydraulic integrated circuit, generally known as the manifold system (valve type) is designed to
control all or part of machine functions by integrating various hydraulic cartridge valves into a
manifold to provide directional, pressure, flow, and load control.

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page 1-3
HYDRAULIC FLUID
Handling Precautions
PERSONS IN REGULAR CONTACT WITH MINERAL-BASED
HYDRAULIC FLUID NEED TO BE AWARE OF THE IMPORTANCE OF
THOROUGH HYGIENE, AND THE PROPER METHODS FOR
HANDLING MINERAL OILS IN ORDER TO AVOID POTENTIAL
HAZARDS TO HEALTH.
If mineral- based hydraulic fluid is SPLASHED INTO THE EYES, it must be WASHED OUT
THOROUGHLY using abundant quantities of water. If irritation persists, medical advice should be
sought.
HYDRAULIC FLUID UNDER PRESSURE CAN PENETRATE AND
BURN SKIN, DAMAGE EYES, AND MAY CAUSE SERIOUS INJURY
OR BLINDNESS.
FLUID LEAKS UNDER PRESSURE MAY NOT ALWAYS BE VISIBLE.

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page 1-4
Fluid Recommendations
MEC recommends the use of Mobil 424 hydraulic fluid. Do not substitute with lower grade oils as
pump damage may result.
Hydraulic Fluid Analysis
Use the following as a guide to determine when analysis of the hydraulic fluid is necessary:
• Anytime the hydraulic pump is replaced.
• If fluid discoloration is noticed in the hydraulic reservoir sight gauge tube.
• If after the first 50 hours of operation, the hydraulic filter element is plugged.
• Anytime the hydraulic filter element shows signs of metal contamination.
• Once every six (6) months, under normal operating conditions.
• Every three (3) months, in extremely dusty or dirty operating conditions.
The hydraulic fluid analysis must be done by a qualified laboratory. Always provide the following
information with the test sample.
• Type of hydraulic fluid (see lubrication chart for recommended hydraulic fluid and/or your
records).
• Model and Serial number of machine from which sample was taken.
• Purpose of analysis: pump failure, discoloration, etc.
• Type of analysis: complete to show additive breakdown, acid buildup, viscosity, type and
percent of contaminants; also, comparison to new fluid and recommendations.
Following the above guidelines will prevent premature failure of pumps, cylinder seals, drive
motors, and unnecessary downtime.
If system flushing and replacement of fluid is recommended, refer to the flushing procedure.

"3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications March 2008
Page 1-5
System Flushing Procedure
1. With platform fully down, drain hydraulic fluid from hydraulic reservoir into a clean, empty
container. Use an oil filter cart so the fluid may be reused if analysis is good.
2. When the hydraulic reservoir is empty, remove suction strainer and hoses.
3. Remove the bypass filter and hose.
4. Flush the hoses with clean hydraulic fluid.
5. Discard old bypass filter element and replace.
6. Flush out the tank with hoses removed from the hydraulic reservoir.
7. Reinstall all hoses removed in the previous steps.
8. Fill hydraulic reservoir with filtered, fresh hydraulic fluid (refer to Lubrication Chart).
9. Loosen output hose fittings at pump to flood with hydraulic fluid. Tighten fittings.
10. Start up the machine. Briefly operate all functions. Two or three lift cycles may be neces-
sary to purge all air from lift cylinder(s).
11. When the above procedures have been completed, fill hydraulic reservoir to full mark on
sight gauge.
12. Check all leaks and correct as necessary. Machine is now ready to be placed back in
operation.
NOTE: AVOID MIXING PETROLEUM AND SYNTHETIC BASE OILS. IT IS NOT
ADVISABLE TO MIX OILS OF DIFFERENT BRANDS OR TYPES, EXCEPT AS
RECOMMENDED.

March 2008 "3072RT / 3772RT / 3772RT HD" Service & Parts Manual - ANSI Specifications
Page 1-6
ART_X72-Lube1
Filler Cap
Sight
Gauge
Drain Plug
Filter Element
HYDRAULIC FLUID RESERVOIR
This consists of the tank, a filler cap with breather, a drain plug, a sight gauge, and a bypass filter
with a 10 micron filter element.
• Check tank for signs of leakage, every week.
Hydraulic Reservoir Assembly
All machines are produced with a filter. It is a 10 micron spin-on, bypassing filter. When the filter is
clogged, hydraulic flow bypasses the filter element. The filter element must be changed every six
( 6) months or 500 hours. Extremely dirty conditions may require that the filter be replaced more
often.
BEWARE OF HOT OIL. CONTACT WITH HOT OIL MAY CAUSE
SEVERE BURNS.