ML50-20 rev 7 · ml50-20 maintenance lift tesco equipment llc ml50-20 maintenance lift operation...

MAINTENANCE LIFT

Operator

Manufactured by

Tl8t:D TE co EQUIPf\.fENT LLCCoral Springs, Florida

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ML50-20 MAINTENANCE LIFT TESCO EQUIPMENT LLC

ML50-20 MAINTENANCE LIFT

OPERATION AND MAINTENANCE MANUALWITH

ILLUSTRATED PARTS LIST

EDITION 3, JANUARY 2011FOR USE WITH ML50-20 MAINTENANCE LIFT

Revision 8

PREPARED FOR Federal Express

SERIAL NUMBER:14-04-11475-F-ML5020 TO 14-04-11488-F-ML5020

and up

FedEx Asset No.502469 TO 502482

and up

MANUFACTURED BY

TESCO EQUIPMENT LLC3661 NW 126th AvenueCoral Springs, FL 33065

TELEPHONE: (954) 752-7994FAX: (954) 341-3802

http://www.tescohilift.com/

January 2015

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RECORD OF REVISIONS

REV.NO.

ISSUEDATE

INSERTDATE BY REV.

NO.ISSUEDATE

INSERTDATE BY

1 1/11

2 5/11

3 8/11

4 5/13

5 10/13

6 11/13

7 1/14

Jan. 14

8 1/15

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LIST OF EFFECTIVE PAGES

Chapter/Section Page(s) Revison Level/Date Shown

Cover Rev. 7 / Jan. 14

Editon Page Rev. 8 / Jan.15

Record of Revisions Rev. 8 / Jan. 15

List of Effective Pages 1 Rev. 8 / Jan. 15

1-1 2 Rev. 7 / Jan. 14

1-1 2 Rev. 7 / Jan. 14

1-2 4 Rev. 7 / Jan. 14

1-2 5 Rev. 1 / Jan. 11

1-2 9 Rev. 7 / Jan. 14

1-2 13 Rev. 7 / Jan. 14

1-3 1 Rev. 7 / Jan. 14

2-Contents 1-2 Rev. 7 / Jan. 14

2-Figures 1 Rev. 7 / Jan. 14

2-2 4 Rev. 2 / May 11

2-2 5 Rev. 7 / Jan. 14

2-5 1 Rev. 7 / Jan. 14

2-5 2-3 Rev. 6 / Nov. 13

2-5 6-12 Rev. 7 / Jan. 14

4-Contents 1 Rev. 1 / Jan. 11

4-1 2 Rev. 1 / Jan. 11

4-1 3 Rev. 7 / Jan. 14

4-4 1 Rev. 1 / Jan. 11

4-4 2 Rev. 7 / Jan. 14

4-4 7-10 Rev. 7 / Jan. 14

4-4 12-13 Rev. 1 / Jan. 11

4-4 14 Rev. 7 / Jan. 14

Jan. 14

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1-1Page 2

TESCO EQUIPMENT LLC ML50-20 MAINTENANCE LIFT

4-4 16 Rev. 1 / Jan. 11

4-4 20 Rev. 7 / Jan. 14

4-4 21 Rev. 1 / Jan. 11

4-4 22 Rev. 7 / Jan. 14

4-4 23-26 Rev. 1 / Jan. 11

4-4 8-9 Rev. 8 / Jan. 15

5-Contents 1 Rev. 7 / Jan. 14

Chapter/Section Page(s) Revison Level/Date Shown

Jan. 14

5-5 1-6 Rev. 7 / Jan. 14

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This manual contains information for the ML50-20 Maintenance Lift and includes: general information,operating procedures, maintenance, overhaul/repairs, and illustrated parts list.

It is a compilation of the best information available at the time of writing. Tesco strives to be the best in theindustry; however, we realize that there is always room for improvement. If you have any comments orcorrections to this manual that you feel should be addressed, please contact us by phone or fax. We will reviewyour suggestions promptly and take any necessary actions required to improve.

Your new ML50-20 unit’s serial number can be found on the “Serial Number/Mfg. Nameplate,” which is locatedon the scissor lift unit’s lower left side frame rail.

Thank you for letting Tesco Equipment LLC serve your ground support equipment needs.

CONFIDENTIALTHIS MANUAL CONTAINS CONFIDENTIAL AND PROPRIETARY INFORMATION OF TESCO EQUIPMENTLLC AND CANNOT BE DUPLICATED, USED OR DISCLOSED IN WHOLE OR IN PART WITHOUTWRITTEN AUTHORIZATION FROM TESCO EQUIPMENT LLC.

© 2008 TESCO EQUIPMENT LLC, all rights reserved as an unpublished work.

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LIMITED WARRANTYTesco Equipment LLC warrants to the original purchaser all Tesco equipment against defective materials orworkmanship (but not against failures or defects resulting, directly or indirectly, from accident, abuse,modification, alteration, lack of recommended maintenance, normal wear and tear, misuse, use of parts andcomponents not recommended by Tesco, or use for purposes not reasonably intended) for a period of twelve(12) months from the date of shipment to the original purchaser. The warrant of purchased functionalcomponents is limited to that specified by the component manufacturer.

THIS LIMITED WARRANTY IS NOT ASSIGNABLE BY THE ORIGINAL PURCHASER OF TESCOEQUIPMENT. ANY PURPORTED ASSIGNMENT OF THIS LIMITED WARRANTY SHALL BE VOID ANDTESCO SHALL HAVE NO OBLIGATION TO HONOR OR PERFORM UNDER THIS LIMITED WARRANTY INFAVOR OF ANY PERSON OR ENTITY OTHER THAN THE ORIGINAL PURCHASER.

Tesco will, at its sole option, repair or replace any component, part or parts, if found on examination by Tescoto be defective and if the necessary return charges are prepaid by the original purchaser. Installation labor willbe the original purchaser’s responsibility. The above only applies to Tesco manufactured components.Purchased components will be handled based on their individual warranties.

THIS ABOVE WARRANTY AND THE ABOVE OBLIGATION TO REPAIR OR REPLACE ARE COMPLETEAND INCLUSIVE. THIS LIMITED WARRANTY IS GIVEN IN LIEU OF ALL OTHER WARRANTIES,EXPRESSED OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY ANDFITNESS FOR A PARTICULAR PURPOSE. ANY IMPLIED WARRANTIES, WHICH MAY BE FOUND INCONNECTION WITH THE PRODUCT, ARE HEREBY LIMITED IN DURATION TO NINETY (90) DAYS FROMTHE DATE OF SHIPMENT TO THE ORIGINAL PURCHASER.

THE SOLE AND EXCLUSIVE REMEDY OF ANY PERSON, AND THE SOLE AND EXCLUSIVE OBLIGATIONAND LIABILITY OF TESCO WITH RESPECT TO TESCO EQUIPMENT IS THE LIMITED WARRANTY SETFORTH HEREIN. TESCO SHALL NOT BE RESPONSIBLE OR LIABLE FOR ANY DAMAGES, WHETHERARISING IN CONTRACT OR IN TORT, OR FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES,INCLUDING LOSS OF USE AND LOST PROFITS, IN CONNECTION WITH THE PURCHASE, SALES,SHIPMENT, SERVICE, REPAIR OR OPERATION OF ANY TESCO EQUIPMENT. IN NO EVENT SHALLTESCO LIABILITY TO ANY PERSON EXCEED THE PURCHASE PRICE OF THE TESCO EQUIPMENT.

Any expense incurred without Tesco’s prior consent for repairs or replacement will not be allowed. Allmodifications by the end-user must be approved by Tesco in writing in order that the expressed warrantyremain in effect.

Tesco reserves the right to make changes in design and changes or improvements upon its products withoutany obligation upon itself to install the same upon its products theretofore manufactured.

Hi-Lifts with known failed or defective parts must be immediately removed from service.

This warranty requires proper and timely maintenance and periodic inspections of the Tesco Hi-Lift asindicated in the operator’s manual furnished with each Tesco unit. The cost of routine or required maintenanceand service is the responsibility of the customer. The customer is required to keep documented evidence ofwhen and by whom maintenance and service are performed.

Inquires concerning this limited warranty should be addressed to:

Tesco Equipment LLC Phone Number: (954) 752-79943661 NW 126th Avenue Fax Number: (954) 341-3802Coral Springs, FL 33065

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Warnings/CautionsPage 1


LIST OF WARNINGS AND CAUTIONS USED IN THIS MANUAL

WARNING

A WARNING MEANS THAT A PROCEDURE THAT FOLLOWS COULD CAUSE DEATH OR INJURY TO YOU OR OTHER PERSONNEL IN THE AREA IF THE PROCEDURE IS NOT FOLLOWED AS WRITTEN.

CAUTION

A CAUTION MEANS THAT A PROCEDURE THAT FOLLOWS COULD CAUSE DAMAGE TO EQUIPMENT IF THE PROCEDURE IS NOT FOLLOWED AS WRITTEN.

The following warnings and cautions are used in this manual. Read all of them and follow the instructions whenperforming the procedures.

WARNING

DO NOT OPERATE THE HI-LIFT DEVICE UNLESS YOU HAVE BEEN TRAINED IN THE SAFE OPERATION OF THE UNIT AND ARE FAMILIAR WITH THE INSTRUCTIONS AND SAFETY WARNINGS CONTAINED IN THIS MANUAL. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

DO NOT OPERATE A HI-LIFT UNIT THAT HAS VISIBLE DAMAGE TO STRUCTURAL OR HYDRAULIC COMPONENTS INCLUDING HOSES. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

DO NOT ATTEMPT TO STABILIZE A HI-LIFT UNIT ON SOFT GROUND OR ON INCLINES BY SHIMMING STABILIZER’S. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

DO NOT RETRACT OR ADJUST STABILIZERS WHEN HI-LIFT UNIT IS IN RAISED POSITION. TAMPERING WITH THE STABILIZER CONTROLS OR STABILIZERS MAY CAUSE THE UNIT TO BE UNSTABLE. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

DO NOT RAISE THE HI-LIFT UNIT UNLESS THE STABILIZERS HAVE BEEN DEPLOYED. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

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WARNING

THE HI-LIFT UNIT AND COMPONENTS ARE NOT INSULATED AGAINST ELECTRICAL SHOCK. ENSURE PROPER CLEARANCE AROUND THE BODY/PLATFORM AND HI-LIFT STRUCTURE. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

ENSURE ALL PERSONNEL ARE STANDING CLEAR OF STABILIZERS AND STABILIZER PAD CONTACT AREA WHEN DEPLOYING AND RETRACTING STABILIZERS. CRUSHING AND/OR PINCHING INJURY MAY RESULT.

WARNING

DO NOT ATTEMPT TO PERFORM ANY MAINTENANCE WORK OR REPAIRS ON A RAISED SCISSOR LIFT/PLATFORM WITHOUT ENGAGING THE MAINTENANCE PROP. FAILURE TO COMPLY COULD CAUSE DEATH OR INJURY.

CAUTION

DO NOT LEAVE WHEN HI-LIFT UNIT IS IN RAISED POSITION UNATTENDED.

WARNING

DO NOT DRIVE OR MOVE THE TRUCK IF ANY OF THE INDICATOR WARNING LIGHTS ON THE DASH BOARD ARE LIT. SERIOUS INJURY TO OPERATOR OR DAMAGE TO THE UNIT MAY RESULT.

WARNING

STAND CLEAR OF STABILIZERS PAD, WHILE OPERATING THE STABILIZER CONTROLS. CRUSHING INJURY TO OPERATORS FEET COULD RESULT.

WARNING

DO NOT ATTEMPT TO RAISE THE WORK PLATFORM UNLESS THE STABLIZERS ARE EXTENDED AND SET. SERIOUS INJURY OR DEATH TO OPEATOR MAY RESULT IF UNIT UPSETS.

WARNING

DO NOT OVERLOAD HI-LIFT UNIT, DO NOT EXCEED THE RATED CAPACITY. SERIOUS DAMAGE TO THE HI-LIFT WILL RESULT, WITH POSSIBLE INJURY TO OPERATORS.

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CAUTION

MAINTAIN A SPACE OF AT LEAST 12 IN (304 MM) BETWEEN THE AIRCRAFT AND WORK PLATFORM. DO NOT MAKE CONTACT WITH ANY PART OF THE AIRCRAFT.

CAUTION

THE HI-LIFT MUST BE PROPERLY STOWED BEFORE ATTEMPTING TO DRIVE THE VEHICLE. INDICATOR LIGHTS WILL BE LIT IF THE HI-LIFT IS NOT IN THE STOWED POSITION. SERIOUS DAMAGE CAN OCCUR IF THE VEHICLE IS MOVED WITHOUT PROPERLY STOWING THE HI-LIFT.

WARNING

ENSURE THAT THE HI-LIFT IS FULLY LOWERED BEFORE ATTEMPING TO RETRACT STABILIZERS.

CAUTION

STAND CLEAR OF DESCENDING HI-LIFT. SERIOUS INJURY TO OPERATOR MAY OCCUR IF STRUCK BY DESCENDING LIFT.

CAUTION

DO NOT SHIP THE UNIT ABOVE DECK WHERE IT CAN BE EXPOSED TO SALT WATER.

CAUTION

AFTER PERFORMING MAINTENANCE ON THE HI-LIFT, DISPOSE OF ANY ENVIRONMENTALLY SENSITIVE MATERIALS ACCORDING TO LOCAL ENVIRONMENTAL REGULATIONS. EXAMPLES OF SUCH MATERIALS INCLUDE: BATTERIES, RUBBER BELTS, LUBRICANTS (MOTOR OILS AND GREASE), AND HYDRAULIC OIL.

WARNING

THE SCISSOR LIFT MUST BE SECURED WITH THE MAINTENANCE PROP BEFORE ACCESSING THE GREASE POINTS.

WARNING

BEFORE STARTING ANY ADJUSTMENT PROCEDURE THAT REQUIRES THE PLATFORM TO BE IN AN ELEVATED POSITION, MOVE THE MAINTENANCE STAND INTO POSITION AND LOWER THE PLATFORM FULLY AGAINST THE MAINTENANCE PROP.

WARNING

IT IS MANDATORY THAT EYE PROTECTION (SAFETY GOGGLES OR FACE SHIELD) BE WORN

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WHEN MAKING PRESSURE CHECKS AND/OR ADJUSTMENTS ON THE HYDRAULIC SYSTEM. HYDRAULIC OIL WILL CAUSE EYE INJURIES. IF HYDRAULIC OIL GETS ON THE SKIN, WASH AFFECTED AREA IMMEDIATELY TO AVOID IRRITATION.

WARNING

DRIVE WHEELS MUST BE CHOCKED TO PREVENT MOVEMENT OF THE UNIT IN EITHER DIRECTION.

WARNING

WHEN MAKING PRESSURE CHECKS OR ADJUSTMENTS, USE GAUGES WITH KNOWN ACCURACY. IMPROPER HYDRAULIC ADJUSTMENTS CAN CAUSE INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT.

WARNING

DO NOT REMOVE GAUGE PORT PLUGS OR GAUGES, OR LOOSEN HYDRAULIC CONNECTIONS WITH THE UNIT RUNNING. HYDRAULIC PRESSURE IN THE SYSTEMS COULD CAUSE HYDRAULIC OIL TO SPRAY ON PERSONNEL.

CAUTION

USE EXTREME CARE TO PREVENT CONTAMINATION OF HYDRAULIC SYSTEM WHEN INSTALLING GAUGES, FITTINGS, OR REPLACING A COMPONENT. CONTAMINATION CAN RESULT IN EQUIPMENT DAMAGE.

CAUTION

WHENEVER AN ADJUSTABLE HYDRAULIC RELIEF VALVE OR PRESSURE REDUCING VALVE IS REPLACED, REDUCE THE PRESSURE SETTING PRIOR TO STARTING THE UNIT. ADJUST THE REPLACED COMPONENT TO SPECIFICATION AS OUTLINED IN THE ADJUSTMENT PROCEDURES.

CAUTION

WHEN MAKING HYDRAULIC SYSTEM ADJUSTMENTS, THE HYDRAULIC OIL MUST BE AT NORMAL OPERATING TEMPERATURE.

WARNING

ONLY QUALIFIED TECHNICIANS, WHO HAVE BEEN TRAINED IN THE USE AND OPERATION OF THIS EQUIPMENT, SHOULD ATTEMPT ANY TROUBLESHOOTING. THE CHASSIS WHEELS MUST BE CHOCKED TO PREVENT THE HI-LIFT UNIT FROM MOVING IN EITHER DIRECTION. THE MAINTENANCE PROP MUST BE INSTALLED FOR SUPPORT WHENEVER THE PLATFORM IS RAISED FOR MAINTENANCE OR ADJUSTMENTS. FAILURE TO FOLLOW GOOD SAFETY PRACTICES DURING MAINTENANCE OR TROUBLESHOOTING COULD RESULT IN DEATH OR SERIOUS INJURY TO PERSONNEL AND/OR DAMAGE TO EQUIPMENT.

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WARNING

DO NOT ALLOW PERSONNEL UNDER THE HI-LIFT UNLESS THE MAINTENANCE PROPS ARE IN PLACE. FAILURE TO SUPPORT THE PLATFORM MAY ALLOW PLATFORM TO FALL, RESULTING IN DEATH OR INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT.

WARNING

USE EYE PROTECTION AND PROTECTIVE CLOTHING RECOMMENDED BY THE MANUFACTURER OF THE WELDING EQUIPMENT THAT IS USED.

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1-ContentsPage 1

Page


TABLE OF CONTENTS

CHAPTER 1: GENERAL INFORMATION AND OPERATING INSTRUCTIONS

Section 1: DescriptionDESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

MAJOR COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Scissor Lift Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Platform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Telescopic Stabilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Control Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Hydraulic System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Section 2: OperationGENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

SAFETY FEATURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Standard Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Safety Interlocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

SAFETY PROCEDURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

CONTROLS AND INDICATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Dash Mounted Indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Lower Control Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Upper Control Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Upper Pendant Control Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Stabilizer Control Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

HI-LIFT VEHICLE OPERATING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Preliminary Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Driving the Vehicle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Hi-Lift (Body) Control Station Operating Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Returning Vehicle to Normal Driving Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

MAINTENANCE PROP OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

EMERGENCY FEATURES – OPERATING PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Manual Emergency Handpump Retracting (Stowing) Stabilizers . . . . . . . . . . . . . . . . . . . . . . . 13Emergency Hi-Lift Lowering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Section 3: SpecificationsDIMENSIONS & WEIGHT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

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1-ContentsPage 2


CAPACITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

PERFORMANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

MAJOR COMPONENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Chassis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Platform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Hi-Lift Single Acting Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Double Acting Stabilizer Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Hydraulic System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Section 4: ShippingGENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

DOMESTIC SHIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

OVERSEAS SHIPMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 5: StorageSHORT-TERM STORAGE – ONE MONTH MAXIMUM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

LONG-TERM STORAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

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1-FiguresPage 1


LIST OF FIGURES


Section 1: Description

1-1 Figure 1 ML50-20 MAINTENANCE LIFT....................................................................... Page 2

Section 2: Operation

1-2 Figure 1 CONTROL STATION LOCATION................................................................... Page 4

1-2 Figure 2 DASH MOUNTED INDICATORS .................................................................... Page 5

1-2 Figure 3 LOWER CONTROL STATION ........................................................................ Page 6

1-2 Figure 4 UPPER CONTROL STATION......................................................................... Page 7

1-2 Figure 5 UPPER PENDANT CONTROL STATION....................................................... Page 8

1-2 Figure 6 STABILIZER CONTROL STATION................................................................. Page 9

1-2 Figure 7 MAINTENANCE PROP INSTALLED............................................................... Page 12

1-2 Figure 8 EMERGENCY OVERRIDE PROCEDURE...................................................... Page 13

1-2 Figure 9 EMERGENCY HI-LIFT CYLINDER LOWERING ............................................ Page 14

Section 3: Specifications

1-3 Figure 1 TYPICAL ML50-20 MAINTENANCE LIFT - SIDE VIEW................................. Page 3

1-3 Figure 2 TYPICAL ML50-20 MAINTENANCE LIFT - REAR VIEW ............................... Page 4

Section 4: Shipping

Section 5: Storage

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DESCRIPTION 1-1Page 1



Section 1: Description

1. DESCRIPTION

The Tesco ML50-20 Maintenance Lift is designed to maintain and inspect aircraft.

The ML50-20 is a scissor hi-lift unit mounted on a commercial truck chassis with a minimum grossvehicle weight (GVW) rating of 14,500 lb (6577 kg). The work platform operates from a minimum of 52.5in (1.33 m) floor height up to a maximum 228 in (5.8 m) floor height. The maximum payload capacity is3,000 lb (1361 kg).

The ML50-20 is designed and manufactured in full compliance with existing ANSI/SIA A92.2-2001,ANSI/SIA A92.7-1998, SAE and OSHA safety standards.

2. MAJOR COMPONENTS

A. Chassis

Any commercially available truck chassis that meets the Gross Vehicle Weight (G.V.W.) rating,and 120” of Cab to Axle (CA) dimension requirements can be used.

NOTE: Refer to the chassis manufacturer’s manual for further information.

B. Scissor Lift Unit

The ML50-20 consists of two single acting (power up/gravity down) telescopic hydraulic cylinders.

Each of the two (2) hydraulic cylinders is equipped with a positive locking safety holding valve,which will stop and hold the hi-lift in a raised position.

C. Platform

The platform’s floor surface consists of grating. Three (3) safety harness restraint D-rings aremounted in the floor. The folding side and socket mounted end safety handrails are 41 in (1.04m) high and constructed of structural steel tubing. The platform has 99 ft2 (9.2 m2) of workingsurface. The perimeter outside edges are fitted with non-marking rubber bumpers to protect theaircraft from any inadvertent contact.

D. Telescopic Stabilizers

Four (4) double acting telescopic stablizers are mounted to the lower scissor frame, two (2) on thefront of the frame and (2) on the back of the frame. The stabilizers are designed to deploy straightdown via double acting, hard industrial chrome-plated hydraulic cylinders, which are mountedinside the stabilizer leg housing. Each stabilizer is equipped with a double, pilot operated safety-holding valve, which safeguards the stabilizers from inadvertently retracting after being set orextending while driving the vehicle.

NOTE: The Telescopic Stabilizers are not designed to lift the entire vehicle’s weight from the ground. The stabilizers are designed to work in conjunction with the vehicle chassis suspension during hi-lift operation.

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GENERAL INFORMATION AND OPERATING INSTRUCTIONS1-1Page 2


Figure 1ML50-20 MAINTENANCE LIFT

SCISSORS

PLATFORM

TELESCOPICSTABILIZERS

STEPS

CHASSIS LOWER CONTROL

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DESCRIPTION 1-1Page 3


E. Control Stations

Four (4) control stations operate the Hi-Lift functions.

The lower control station is located on the driver side forward chassis frame. It is equipped withthree (3) push buttons to operate the hi-lift up and down functions, and a beacon switch. It alsocontains a mushroom head emergency stop switch.

The two (2) upper control stations are located at the forward left corner of the platform. Oneupper control is mounted on a pedestal and equipped with rotary type switches to operate worklights, remote engine stop and start, and compressor off and on, and a mushroom heademergency stop switch. Another upper control is pendant type enclosure. It is equipped with three(3) push buttons to operate the hi-lift up and down functions and a mushroom head emergencystop switch.

The fourth control station operates the stabilizers. The stabilizer control station is located on thedriver side center chassis frame. It is equipped with two (2) momentary push buttons to retractand extend the stabilizers. The stabilizers must be extended before the platform can be raised.

The dash inside of the cab also has indicator lights for lift and stabilizer functions.

F. Hydraulic System

The hydraulic system supplies the actuating power to the stabilizers and hi-lift. An arrangementof valves regulates fluid flow from the engine-driven pump to the actuating cylinders duringoperation. An adjustable relief valve controls the system pressure, and restrictor valves regulaterates of flow. Load holding valves prevent retraction of the platform lift cylinders and the stabilizercylinders if power is lost. The electrical system actuates the solenoid valves. See Chapter 2,Section 5 for schematic diagram.

G. Electrical System

The electrical system provides control circuits for the hydraulic system, chassis interface, andlighting. The chassis electrical system supplies system power. Manual switches permit operatorcontrol of the system. Inter-connected limit switches and relays assure proper operationalsequence. Circuit breakers protect the system from overloads. See Chapter 2, Section 5 forschematic diagram.

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OPERATION 1-2Page 1


Section 2: Operation

1. GENERAL INFORMATION

“Safety First!” is the motto at Tesco; therefore, the first part of the Operation section begins with safetyfeatures and procedures. Operation of the Tesco ML50-20 Maintenance Lift should not be conducteduntil the operator is familiar with all the safety features and procedures associated with the ML50-20Maintenance Lift. It is strongly advised that this manual be read completely prior to operating the vehicle.

WARNING

DO NOT OPERATE THE HI-LIFT DEVICE UNLESS YOU HAVE BEEN TRAINED IN THE SAFE OPERATION OF THE UNIT AND ARE FAMILIAR WITH THE INSTRUCTIONS AND SAFETY WARNINGS CONTAINED IN THIS MANUAL. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

DO NOT OPERATE A HI-LIFT UNIT THAT HAS VISIBLE DAMAGE TO STRUCTURAL OR HYDRAULIC COMPONENTS INCLUDING HOSES. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING


WARNING

DO NOT RETRACT OR ADJUST STABILIZERS WHEN HI-LIFT UNIT IS IN RAISED POSITION. TAMPERING WITH THE STABILIZER CONTROLS OR STABILIZERS MAY CAUSE THE UNIT TO BE UNSTABLE. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

WARNING

DO NOT RAISE THE HI-LIFT UNIT UNLESS THE STABILIZERS HAVE BEEN DEPLOYED. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

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1-2Page 2


WARNING


WARNING

ENSURE ALL PERSONNEL ARE STANDING CLEAR OF STABILIZERS AND STABILIZER PAD CONTACT AREA WHEN DEPLOYING AND RETRACTING STABILIZERS. CRUSHING AND/OR PINCHING INJURY MAY RESULT.

WARNING


CAUTION

DO NOT LEAVE WHEN HI-LIFT UNIT IS IN RAISED POSITION UNATTENDED.

2. SAFETY FEATURES

A. Standard Features

• Headlights

• Combination tail and stoplights

• Back up lights

• Turn signals and hazard warning

• Parking brake

• Emergency lowering

• Handrails around platform

• Maintenance prop for maintenance access beneath platform

B. Safety Interlocks

• Stabilizers and hi-lift will not operate unless the transmission shift lever is set on neutral or parkand the parking brake is on.

• Stabilizers cannot be retracted unless the Hi-Lift is fully lowered.

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OPERATION 1-2Page 3


• The vehicle cannot be moved or driven while in lift mode.

NOTE: When parking brake is on, it will activate the LIFT mode. With the parking brake off the unit will be in DRIVE mode.

3. SAFETY PROCEDURES

WARNING

DO NOT OPERATE A UNIT THAT HAS VISIBLE DAMAGE TO STRUCTURAL OR HYDRAULIC COMPONENTS. FAILURE TO HEED WARNINGS MAY RESULT IN SERIOUS INJURY OR DEATH TO OPERATOR AND/OR CREW.

• Ensure operator and crew are familiar with all phases of the units operation.

• Follow the local station safety rules and regulations, including the safe maximum load capacities of the equipment.

• Visually check the vehicle’s overall condition. DO NOT operate the vehicle if any defects or damage are noted.

• Ensure all appropriate routine maintenance and inspections have been performed.

• Keep hands and feet clear of the vehicle’s tires and Hi-Lift mechanism.

• Securely fasten seat belt before driving the vehicle.

• Ensure the vehicle is stopped, transmission is in neutral, and manual parking brake is set before dismounting the vehicle.

• DO NOT shift transmission into gear when engine speed is above idle.

• Ensure vehicle is at a complete stop before shifting gears.

• Ensure path is clear before backing up. Follow your local established procedures for alerting other personnel prior to back up.

• Exercise extra caution in congested areas and around blind corners.

• DO NOT operate the vehicle at speeds higher than conditions permit.

• DO NOT attempt to drive the vehicle with the platform partially raised or the stabilizers deployed.

• Slow vehicle to a creep speed when approaching within 20 ft (6 m) of the aircraft.

• Stop vehicle when the platform’s bumper is approximately 12 in (304 mm) from the aircraft.

• Ensure that ample overhead clearance is available, and no soft ground or obstructions are present under the stabilizers pad contact area.

• Ensure personnel are clear of the platform’s path before lowering hi-lift.

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1-2Page 4


Figure 1CONTROL STATION LOCATION

UPPER FIXED AND PENDANTCONTROL STATIONS

LOWER CONTROLSTATION

DASH MOUNTEDINDICATORS

STABILIZERCONTROLSTATION

ELECTRICAL PANEL BOX

HYDRAULICENCLOSURE/TANK

MANUALOVERRIDE VALVES

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OPERATION 1-2Page 5


4. CONTROLS AND INDICATORS

A. Dash Mounted Indicators

WARNING

DO NOT DRIVE OR MOVE THE TRUCK IF ANY OF THE INDICATOR WARNING LIGHTS ON THE DASH BOARD ARE LIT. SERIOUS INJURY TO OPERATOR OR DAMAGE TO THE UNIT MAY RESULT.

NOTE: Stabilizers and hi-lift will not operate unless the transmission shift lever is set to NEUTRAL/PARK and parking brake is ON.

NOTE: Indicator light will indicate only if engine running.

(1) LIFT UP INDICATOR LIGHT (RED) – when lit, indicates lift out of rest.

(2) STABILIZERS EXTENDED INDICATOR LIGHT (AMBER) – when lit, indicates the stabilizers are extended.

(3) LIFT READY INDICATOR LIGHTS (GREEN) – illuminates when the unit is in LIFT MODE (transmission is in neutral or park, parking brake set), and the platform can be raised or lowered if stabilizers set.

(4) SHORE POWER INDICATOR LIGHT (RED) – When lit, indicates that the unit is connected to an outside electrical source.

NOTE: Truck will shut off when shift into gear with shore power.

Figure 2DASH MOUNTED INDICATORS

1 2 43

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1-2Page 6


B. Lower Control Station

NOTE: In the event of an emergency, depress the red mushroom head control marked EMERGENCY STOP. This cuts power to all control switches and stop the engine. To reset the EMERGENCY STOP, rotate the red mushroom head control clockwise until it releases.

(1) UP SWITCHES – two black push button switches. When both buttons are depressed simultaneously and if the stabilizers are extended, the platform will rise.

NOTE: The hi-lift cannot be raised unless the stabilizers are extended.

(2) DOWN SWITCH – one black push button switch. When depressed, the platform will descend.

(3) BEACON ON-OFF SWITCH – two-position switch. When turned to ON, the beacon light will illuminate. When turned to OFF, the beacon light will extinguish.

(4) EMERGENCY STOP – red mushroom head push button. Cuts power to the control switches and stop the engine when depressed.

NOTE: The emergency stop button must be reset before the chassis engine will restart.

Figure 3LOWER CONTROL STATION

1

2

3

4

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OPERATION 1-2Page 7


C. Upper Control Station

(Ref. Figure 4)


(1) EMERGENCY STOP – red mushroom head push button. Cuts power to the control switches and stop the engine when depressed.

(2) ENGINE OFF-ON-START – three-position spring return from right to center switch. When turned to the START position, the vehicle's engine will engage. When turned to the OFF position, the vehicle's engine will turn off.

(3) WORK LIGHT ON-OFF SWITCH – two-position switch. When turned to ON, the work light will illuminate. When turned to OFF, the work light will extinguish.

(4) COMPRESSOR ON-OFF SWITCH – two-position switch. Turns compressor On or OFF.

NOTE: Compressor will only turn on when air pressure lowers to a preset value, even though compressor switch is on.

NOTE: The emergency stop button must be reset before the chassis engine will restart.

Figure 4UPPER CONTROL STATION

2

3

4

1

SPARE

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1-2Page 8


D. Upper Pendant Control Station

(Ref. Figure 5)


(1) EMERGENCY STOP – red mushroom head push button. Cuts power to the pendant control switches when depressed.

(2) DOWN SWITCH – one black push button switch. When depressed, the platform will descend.

(3) UP SWITCHES – two black push button switches. When both buttons are depressed simultaneously and if the stabilizers are extended, the platform will rise.

NOTE: The hi-lift cannot be raised unless the stabilizers are extended.

NOTE: The emergency stop button must be reset before the hi-lift functions will operate.

Figure 5UPPER PENDANT CONTROL STATION

3

2

1

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OPERATION 1-2Page 9


E. Stabilizer Control Station

(Ref. Figure 6)

(1) STABILIZER RETRACT – black push button switch. When depressed, returns stabilizers to stowed position.

(2) STABILIZER EXTEND – black push button switch. When depressed, the stabilizers are deployed so that the platform can be raised.

NOTE: All stabilizers must be fully extended before raising lift.

Figure 6STABILIZER CONTROL STATION

5. HI-LIFT VEHICLE OPERATING PROCEDURE

A. Preliminary Checks

The following preliminary check list shall be performed before driving the vehicle.

(1) FUEL LEVEL – DO NOT operate vehicle if fuel level is below ¼ tank.

(2) WHEEL BRAKES – DO NOT operate vehicle if the service brake pedal is resting low near the floorboard or if brake pedal is spongy when brake is applied.

(3) TIRES – DO NOT operate this vehicle if tire pressure is low.

(4) OIL LEVEL – Visually check the level of the hydraulic oil on the hydraulic oil reservoir’s sight gauge.

(5) GENERAL CONDITION – Perform a general walk around visual inspection of the vehicle’s overall condition. DO NOT operate vehicle or Hi-Lift if any damage to the vehicle or structure is seen.

1

2

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B. Driving the Vehicle

(1) Ensure the preliminary checklists have been performed before boarding the driver’s cab and operating the vehicle.

(2) Drive vehicle according to the vehicle operator’s manual and applicable laws.

C. Hi-Lift (Body) Control Station Operating Procedures

Normal Operation Sequence to Raise Unit

(1) Slow vehicle to a creep speed when approaching within 20 ft (6 m) of the aircraft.

(2) Position vehicle on level ground with a space of at least 12 in (304 mm) between the aircraft and work platform. DO NOT make contact with any part of the aircraft.

NOTE: An assistant may be required when positioning the vehicle by the aircraft.

(3) Shift transmission into park and set parking brake.

NOTE: The stabilizers and Hi-Lift functions will not operate unless the transmission is in park and the parking brake is set.

NOTE: Parking brake will activate the LIFT mode.

(4) Dismount the vehicle and extend the stabilizers. Refer to Figure 6.

NOTE: All stabilizers must be fully extended before raising lift.

(5) Set chocks per operational requirements.

WARNING


WARNING

STAND CLEAR OF STABILIZERS PAD, WHILE OPERATING THE STABILIZER CONTROLS. CRUSHING INJURY TO OPERATORS FEET COULD RESULT.

WARNING

DO NOT ATTEMPT TO RAISE THE WORK PLATFORM UNLESS THE STABLIZERS ARE EXTENDED AND SET. SERIOUS INJURY OR DEATH TO OPEATOR MAY RESULT IF UNIT UPSETS.

(6) With the vehicle securely positioned, board the work platform via the boarding steps located at the rear of the unit.

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OPERATION 1-2Page 11


(7) Once onboard the platform, secure the platform’s entryway and locate the upper pendant control station (ref. Figure 1).

(8) Raise the platform by pushing both Up, Up buttons together. Refer to Figure 5.

WARNING


WARNING

DO NOT OVERLOAD HI-LIFT UNIT, DO NOT EXCEED THE RATED CAPACITY. SERIOUS DAMAGE TO THE HI-LIFT WILL RESULT, WITH POSSIBLE INJURY TO OPERATORS.

CAUTION

MAINTAIN A SPACE OF AT LEAST 12 IN (304 MM) BETWEEN THE AIRCRAFT AND WORK PLATFORM. DO NOT MAKE CONTACT WITH ANY PART OF THE AIRCRAFT.


(9) Once the platform is at desired height, the vehicle's engine may be turned off. Rotate the ENGINE OFF-ON-START switch to the OFF position. Refer to Figure 4

Normal Operation Sequence to Lower Unit

(10) Ensure all personnel are away from under the platform before proceeding.

(11) If the engine has been turned off, rotating the engine switch to the START position will restart the chassis engine.

(12) From the upper control station push the DOWN button, and lower the unit until it is in its full resting position.

CAUTION

THE HI-LIFT MUST BE PROPERLY STOWED BEFORE ATTEMPTING TO DRIVE THE VEHICLE. INDICATOR LIGHTS WILL BE LIT IF THE HI-LIFT IS NOT IN THE STOWED POSITION. SERIOUS DAMAGE CAN OCCUR IF THE VEHICLE IS MOVED WITHOUT PROPERLY STOWING THE HI-LIFT.

D. Returning Vehicle to Normal Driving Condition

(1) Ensure the Hi-Lift is fully lowered, and all stabilizers are fully retracted.

NOTE: Stabilize the engine by allowing it to idle before retracting the stabilizers.

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1-2Page 12


(2) Mount vehicle cab and release parking brake. Check the dash mounted warning lights. They should all be extinguished. (e.g., stabilizer and lift are retracted and brake is released.)

NOTE: Attempting to drive the vehicle while in LIFT MODE (parking brake on) will stop the engine. Return the gear selector to NEUTRAL or PARK, and releases the parking brake to activate DRIVE MODE.

6. MAINTENANCE PROP OPERATION

WARNING


The maintenance prop must be used during all service and maintenance where the lift must be raisedand personnel must be under the lifted platform. The maintenance prop is at the rear of the Hi-Lift. Themaintenance prop is designed to be quick and easy so as not to discourage maintenance personnelfrom using it.

1. Raise the scissor high enough to clear the maintenance prop when swung upwards into the raised position.

2. Rotate the maintenance prop up to a vertical position.

3. Lock the maintenance prop into position by inserting the Lock pin through the locking tabs and prop (ref. Figure 7).

4. Lower the scissor securing the maintenance prop in the support position.

5. To remove the maintenance prop, raise the scissor high enough to disengage the maintenance prop and provide clearance for the maintenance prop to swing down.

6. Remove the Lock pin (ref. Figure 7).

7. Rotate the maintenance prop down to the stored position.

Figure 7MAINTENANCE PROP INSTALLED

MAINTENANCEPROPRAISED

LOCK PININSTALLED

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OPERATION 1-2Page 13


7. EMERGENCY FEATURES – OPERATING PROCEDURES

Figure 8EMERGENCY OVERRIDE PROCEDURE

A. Manual Emergency Handpump Retracting (Stowing) Stabilizers

WARNING

ENSURE THAT THE HI-LIFT IS FULLY LOWERED BEFORE ATTEMPING TO RETRACT STABILIZERS.

(1) Insert handle into Handpump (ref. Figure 8).

(2) Press and hold valve (A) and pump handle to retract stabilizers.

B

A

HANDPUMP

HANDPUMP HANDLE

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1-2Page 14


B. Emergency Hi-Lift Lowering

CAUTION

STAND CLEAR OF DESCENDING HI-LIFT. SERIOUS INJURY TO OPERATOR MAY OCCUR IF STRUCK BY DESCENDING LIFT.

(1) Close the valve (B) in the hydraulic box (ref. Figure 8) by loosening locknut and turning fully clockwise.

(2) Go under the truck and reach up to the under side of the lift cylinders (ref. Figure 9).

(3) Locate the red manual operation knobs (E).

(4) Push in and turn the red knob counter-clockwise until it pops out.

(5) Return to the box and slowly open the flow control as necessary to bring the lift down safely.

(6) Once down, the valve (E) must be reset by pushing in & twisting clockwise until it locks.

(7) Readjust valve (B) per Hydraulic Adjustment Section 2-2 when unit is functioning again.

Figure 9EMERGENCY HI-LIFT CYLINDER LOWERING

E

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SPECIFICATIONS 1-3Page 1


Section 3: Specifications

1. DIMENSIONS & WEIGHT

NOTE: Refer to the truck manufacturer’s manual for dimensions and weight of the truck.

• Length 266 in (6.76 m)

• Width 110 in (2.79 m)

• Weight 14,500 lb (6577 kg)

• Minimum Platform Floor Height - Stab. Set 52.5 in (1.33 m)

• Maximum Platform Floor Height 228 in (5.8 m)

2. CAPACITY

• Maximum Payload 3,000 lb (1361 kg)

• Hydraulic Fluid Reservoir 32 US gal (121 l)

3. PERFORMANCE

• Hi-lift Raise Speed .27 fps (8.23 cm/s)

• Hi-lift Lowering Speed .26 fps - .20 fps (7.92 cm/s - 6.1 cm/s)

• Hydraulic System Relief Pressure 1,800 psi (11411 kpa)

NOTE: The hi-lift lowering speed noted is pre-set by Tesco. The hi-lift lowering speed can be faster or slower by opening or closing the adjustable flow control valve.

4. MAJOR COMPONENTS

A. Chassis

Please refer to the chassis manufacturer’s manual.

B. Platform

• Length w/Bumper 165 in (4.19 m)

• Width w/Bumper 110 in (2.79 m

• Handrail Height 41 in (1.04 m)

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1-3Page 2


C. Hi-Lift Single Acting Cylinder

• Cylinder Stages 3

• Cylinder Quantity 2

• Stroke 110 in. (2794 mm)

• Fluid Capacity Retracted 3.5 US gal (13.25 l)

• Fluid Capacity Extended 4.8 US gal (18 l)

D. Double Acting Stabilizer Cylinders

• Cylinder Bore Diameter 2.5 in. (63.5 mm)

• Stroke 16 in (406.4 mm)

• Fluid Capacity Retracted 80 in3 (1.31 l)

• Fluid Capacity Extended 80 in3 (1.31 l)

E. Hydraulic System

• Hydraulic Pump Gear Type

• Pump Flow Rating at 1200 RPM’s 18.5 gpm (70L/m)

F. Electrical System

• Servo Control Valve Solenoids 12VDC negative ground

• Master Control Valve Solenoid 12VDC negative ground

• Circuit Solenoid Switch & Relays 12VDC negative ground

• Electrical Circuit Protection Thermal circuit breakers

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SPECIFICATIONS 1-3Page 3


Figure 1TYPICAL ML50-20 MAINTENANCE LIFT - SIDE VIEW

212 in / 5.38 m

266 in / 6.76 m

228 in (5.8 m)- MAX. FLOOR HT.

STAB. SET

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Figure 2TYPICAL ML50-20 MAINTENANCE LIFT - REAR VIEW

93.5 in / 2.37 m- Stab set

110 in / 2.79 mplatform width

52.5 in / 1.33 mmin floor height

- Stab set

51 in / 1.3 mmin floor height

- Stab set

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SHIPPING 1-4Page 1


Section 4: Shipping

1. GENERAL INFORMATION

This section contains general information on preparing the hi-lift unit for transportation domestically andoverseas. Check regulations of the states and/or countries through which the hi-lift unit will betransported for specific requirements.

Review storage requirements (Section 5) for information on protection that may be required if time enroute is expected to be more than two or three days.

2. DOMESTIC SHIPMENT

There are few special preparations needed to ship the unit domestically.

1. Ensure all stabilizers are fully retracted to stowed position.

2. Ensure the work platform is fully lowered and resting firmly in the stowed position on the rest pads.

3. Ensure the folding handrails (optional) are locked in the raised position or the chain post guard-rails are in raised position.

4. Restrain the hi-lift unit with universal tie-down straps, chains and over-center tensioning devices.

NOTE: Refer to the chassis manufacturer’s manual for any preparations the chassis may need before shipping.

3. OVERSEAS SHIPMENT

CAUTION

DO NOT SHIP THE UNIT ABOVE DECK WHERE IT CAN BE EXPOSED TO SALT WATER.

1. Ensure all stabilizers are fully retracted to stowed position, and the work platform is fully lowered. The folding handrails (optional) are to be locked in the raised position or the chain post guardrails are in raised position.

2. Restrain the hi-lift unit with universal tie-down straps, chains, and over-center tensioning devices, and chocks. Inspect all attaching points to ensure that the restraints are secure and that straps (if used) do not bear against angular surfaces that may cause failure en route due to chafing or vibration.

3. Check for any loose items. If necessary, pack the items separately and place in a secure location.

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STORAGE 1-5Page 1


Section 5: Storage

1. SHORT-TERM STORAGE – ONE MONTH MAXIMUM

1. Perform all periodic maintenance services as prescribed in Chapter 2.

2. Chock drive wheels front and rear to prevent movement in any direction.

3. Disconnect and remove the 12-volt battery and store in cool, dry location.

4. Coat all exposed unpainted metal surfaces with rust preventative. Especially important are exposed hydraulic cylinder rods.

2. LONG-TERM STORAGE

1. The unit should be stored in a shelter to protect it. If a shelter is not available, cover it with tarpaulins or other protective material. Instrument panels should be covered and taped to provide a moisture-proof seal.

2. Perform all periodic maintenance services as prescribed in Chapter 2.

3. Raise and block chassis so that all wheels are off ground.

4. Disconnect and remove the 12-volt battery and store in cool, dry location.

5. Coat all exposed unpainted metal surfaces with rust preventative. Especially important are exposed hydraulic cylinder rods.

NOTE: Refer to the chassis manufacturer’s manual for procedures to be performed for chassis preservation for both short-term and long-term storage.

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ML50-20 rev 7 · ml50-20 maintenance lift tesco equipment llc ml50-20 maintenance lift operation...

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