Tesco ML50-30 User manual

MAINTENANCE LIFT
Maintenance Manual

  co 

Property of American Airlines

2-Contents
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Page
ML50-30 MAINTENANCE LIFT TESCO EQUIPMENT LLC
TABLE OF CONTENTS
CHAPTER 2: MAINTENANCE
Section 1: Servicing
PERIODIC MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
HYDRAULIC OIL RECOMMENDATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
CHECKING HYDRAULIC OIL LEVEL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
FILLING HYDRAULIC OIL RESERVOIR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
LUBRICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Grease Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Oil Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Section 2: Hydraulic System Adjustments
HYDRAULIC ADJUSTMENTS - HYDRAULIC POWER MODULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
HYDRAULIC ADJUSTMENTS - TRAVERSING PLATFORM VALVE. . . . . . . . . . . . . . . . . . . . . . . . . . 4
Flow Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
COUNTER BALANCE/HOLDING VALVE-HOLD PRESSURE ADJUSTMENT . . . . . . . . . . . . . . . . . . 5
LIFT DOWN FLOW CONTROL VALVE ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Section 3: Troubleshooting
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
HYDRAULIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
ELECTRICAL SYSTEM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Troubleshooting Chart - General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Section 4: Repairs
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
STRUCTURAL REPAIRS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Scissor arms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Scissor frame or van body. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Handrails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Surface rust or scratches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Section 5: System Schematics
HYDRAULIC SCHEMATIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
4 Stabilizers & 12VDC Pump with Return Filter . . . . . . . . . . . . . . . . . . . . . . . . . Figure 1 . . . . 1
Apr. 17
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TESCO EQUIPMENT LLC ML50-30 MAINTENANCE LIFT
ELECTRICAL SCHEMATIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
How to Read This Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2 . . . . . 1
Electrical Schematic, Engine & Chassis - Sheet 1 of 9 . . . . . . . . . . . . . . . . . . . . Figure 3 . . . . . 1
Electrical Schematic, Lighting - Sheet 2 of 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4 . . . . . 1
Electrical Schematic, Lift & Stab. Control - Sheet 3 of 9 . . . . . . . . . . . . . . . . . . . Figure 5 . . . . . 1
Electrical Schematic, Lift & Stab. Control - Sheet 4 of 9 . . . . . . . . . . . . . . . . . . . Figure 6 . . . . . 1
Electrical Schematic, Options - Sheet 5 of 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 7 . . . . . 1
Electrical Schematic, Options - Sheet 6 of 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 8 . . . . . 1
Electrical Schematic, Options - Sheet 7 of 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 9 . . . . . 1
Electrical Schematic, Tables of Veh. Connections - Sheet 8 of 9 . . . . . . . . . . . . Figure 10 . . . . 1
Electrical Schematic, Tables of Veh. Connections
DPDT & SPDT Relay Wiring - Sheet 9 of 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 11 . . . . 1
Apr. 17
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2-Figures
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ML50-30 MAINTENANCE LIFT TESCO EQUIPMENT LLC
LIST OF FIGURES
CHAPTER 2: MAINTENANCE
Section 1: Servicing
2-1 Figure 1 HYDRAULIC OIL FILL POINT......................................................................... Page 3
2-1 Figure 2 GREASE POINTS DIAGRAM ......................................................................... Page 5
2-1 Figure 3 GREASE POINTS - LIFT CYLINDERS UPPER.............................................. Page 6
2-1 Figure 4 GREASE POINTS - LIFT CYLINDERS BOTTOM........................................... Page 7
2-1 Figure 5 GREASE POINTS - STABILIZERS................................................................. Page 7
2-1 Figure 6 GREASE POINTS - TRAVERSING CYLINDER AND ROLLERS................... Page 8
2-1 Figure 7 GREASE POINTS - SCISSOR ROLLERS AND PINS.................................... Page 9
2-1 Figure 8 GREASE POINT - LOWER BOOSTER ARM.................................................. Page 10
2-1 Figure 9 GREASE POINTS - TRACKS AND BOOSTER ARM UPPER LIP ................. Page 10
2-1 Figure 10 OIL POINTS .................................................................................................... Page 11
Section 2: Hydraulic System Adjustments
2-2 Figure 1 HYDRAULIC SYSTEM.................................................................................... Page 3
2-2 Figure 2 TRAVERSING PLATFORM VALVE................................................................ Page 4
2-2 Figure 3 COUNTER BALANCE/HOLDING VALVE....................................................... Page 5
2-2 Figure 4 LIFT DOWN FLOW CONTROL VALVE ADJUSTMENT................................. Page 6
Section 3: Troubleshooting
Section 4: Repairs
Section 5: System Schematics
2-5 Figure 1 HYDRAULIC SCHEMATIC - 4 STABILIZERS & 12V PUMP
WITH RETURN FILTER.................................................................................. Page 2
2-5 Figure 2 HOW TO READ THIS SCHEMATIC ............................................................... Page 5
2-5 Figure 3 ELECTRICAL SCHEMATIC, ENGINE & CHASSIS - SHEET 1 OF 9............. Page 6
2-5 Figure 4 ELECTRICAL SCHEMATIC, LIGHTING - SHEET 2 OF 9.............................. Page 7
2-5 Figure 5 ELECTRICAL SCHEMATIC, LIFT & STAB. CONTROL - SHEET 3 OF 9...... Page 8
Apr. 17
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2-Figures
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TESCO EQUIPMENT LLC ML50-30 MAINTENANCE LIFT
2-5 Figure 6 ELECTRICAL SCHEMATIC, LIFT & STAB. CONTROL - SHEET 4 OF 9...... Page 9
2-5 Figure 7 ELECTRICAL SCHEMATIC, OPTIONS - SHEET 5 OF 9............................... Page 10
2-5 Figure 8 ELECTRICAL SCHEMATIC, OPTIONS - SHEET 6 OF 9............................... Page 11
2-5 Figure 9 ELECTRICAL SCHEMATIC, OPTIONS - SHEET 7 OF 9............................... Page 12
2-5 Figure 10 ELECTRICAL SCHEMATIC, TABLES OF VEH. CONNECTIONS
- SHEET 8 OF 9 ............................................................................................. Page 13
2-5 Figure 11 ELECTRICAL SCHEMATIC, TABLES OF VEH. CONNECTIONS
DPDT & SPDT RELAY WIRING - SHEET 9 OF 9........................................... Page 14
Apr. 17
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SERVICING 2-1
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ML50-30 MAINTENANCE LIFT TESCO EQUIPMENT LLC
CHAPTER 2: MAINTENANCE
Section 1: Servicing
1. PERIODIC MAINTENANCE
Regular maintenance is required to ensure optimum performance and long life for machine components.
Maintain the unit by performing periodic maintenance at the intervals listed in the Periodic Maintenance
Chart below.
If the unit is being operated in severe weather conditions such as extreme heat or cold, or in sandy,
dusty, or snowy areas, increase the frequency of periodic maintenance as necessary.
NOTE: Refer to the chassis manufacturer’s manual for service requirements to the chassis.
PERIODIC MAINTENANCE CHART
PROCEDURE PERIOD (HOURS)
8250 OTHER
Perform walk-around inspection and check for damage, missing
parts and fluid leaks. X
Check spotlights, indicator lights, and beacon lights. X
Check hydraulic oil level. X
Check condition of all handrails and mounting brackets. X
Check condition of operator’s boarding steps. X
Check fire extinguisher levels. Make sure they are secured in
their mounting brackets. X
Inspect pivot pins on platform cylinders for wear. X
Check scissors pivot pins and rollers for wear. X
Inspect condition of all hydraulic hoses and fittings and check for
leakage. X
Inspect all hydraulic components for fluid leakage. X
Inspect all wiring harnesses for damage and security. X
Check condition of bumpers. X
Check operation of the platform mounted pendant control station. X
Check condition of Hi-Lift/scissors structure. Check for stress
cracks, physical damage, or corrosion. X
Check platform under structure for cracked welds or corrosion. X
Check condition of placards and safety warning decals. X
Mar. 09
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MAINTENANCE
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TESCO EQUIPMENT LLC ML50-30 MAINTENANCE LIFT
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.
2. HYDRAULIC OIL RECOMMENDATIONS
The hydraulic oil reservoir is factory filled with ISO 15 hydraulic oil at the time of shipping.
SEVERE CLIMATE OPERATION
• If platform lowering becomes too slow in severe cold weather operations, a lower viscosity fluid
may be substituted.
3. CHECKING HYDRAULIC OIL LEVEL
Maintaining proper hydraulic oil level is important. DO NOT overfill the hydraulic oil reservoir. Hydraulic
oil expands when heated.
1. The hydraulic oil reservoir is equipped with a sight gauge. Ensure that the Hi-Lift is fully lowered
and stabilizers must be in stowed position when checking hydraulic oil level using the sight
gauge. The oil level should be near the “High” mark and must not be below the “Low” mark.
Replace return filter 6 mos.
Check that all wiring terminals are secure. 6 mos.
Replace corrosion inhibitor in main electrical control box. Annually
Drain hydraulic reservoir and clean. Annually
Check hoist rollers for wear X No more than
1/4” wear
OIL OPERATING TEMPERATURE RANGE
RECOMMENDED
GRADE OF
HYDRAULIC FLUID CLIMATE AMBIENT
TEMPERATURE
MAXIMUM BULK OIL
(RESERVOIR
TEMP.)
ISO 32 Hot Above 60° F (15° C) 180° F (82° C)
ISO 15 Moderate 20° F (-7° C) -100° F (38° C) 165° F (74° C)
ISO 5 Cold Below 32° F (0° C) 150° F (60° C)
PERIODIC MAINTENANCE CHART
PROCEDURE PERIOD (HOURS)
8250 OTHER
Mar. 09
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SERVICING 2-1
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ML50-30 MAINTENANCE LIFT TESCO EQUIPMENT LLC
4. FILLING HYDRAULIC OIL RESERVOIR
1. Check hydraulic oil level as described above.
2. Determine the amount of oil to be added: 2.5 gallons of oil will raise the level in the reservoir
about 1 inch.
3. Raise the work platform if necessary to access the reservoir filler cap. Support platform with the
maintenance stand.
4. Clean the area around the filler/breather cap.
5. Remove cap and check strainer screen for any foreign material.
6. Clean thoroughly before putting hydraulic oil into the reservoir.
7. Use only clean, uncontaminated oil, filtered to 10M. Add the quantity of oil determined in step 2.
8. Secure cap when finished.
9. Recheck hydraulic oil level.
Figure 1
HYDRAULIC OIL FILL POINT
5. LUBRICATION
A. Grease Points
NOTE: Use any commercially available “MP” multipurpose grease which meets NLGI Grade 1 or
2 standards.
Wipe grease fittings clean and apply grease. Before coating tracks with grease, clean surfaces to
remove dirt and foreign material (ref. Figure 2 thru Figure 8).
B. Oil Points
NOTE: Use SAE 5W-30W oil or other adequate Lubricants with brush or oil can as appropriate
(ref. Figure 9).
Lift Cylinder Rods - Apply oil to reduce cylinder noise as needed which may be caused by dry
seals.
HYDRAULIC FILL POINT
(HYDRAULIC OIL ONLY)
Mar. 17
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MAINTENANCE
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TESCO EQUIPMENT LLC ML50-30 MAINTENANCE LIFT
NOTE: The scissors lift must be raised to access the grease points. Make sure to put maintenance
prop up.
NOTE: Check at intervals listed and lubricate as required. In unusual weather conditions, check at
more frequent intervals.
GREASE POINTS
ITEM COMPONENT TOTAL
FITTINGS INTERVAL
1 Scissor pivot pins (Upper/Middle/Lower) 12 6 mos.
2 Scissor Arm End Pins 4 6 mos.
3 Scissor roller (Upper/Lower) 8 6 mos.
4 Traversing roller pins 4 6 mos.
5 Lift cylinder (Upper/Lower) 8 6 mos.
6 Traversing cylinder rod ends 2 6 mos.
7 Booster arm pivot 1 6 mos.
8 Stabilizers 16 6 mos.
9 Roller Tracks 3 mos.
GREASE
Mar. 17
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SERVICING 2-1
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ML50-30 MAINTENANCE LIFT TESCO EQUIPMENT LLC
WARNING
THE SCISSOR LIFT MUST BE SECURED WITH THE MAINTENANCE PROP BEFORE
ACCESSING THE GREASE POINTS.
Figure 2
GREASE POINTS DIAGRAM
Ref. Figure 7
Ref. Figure 8
Ref. Figure 7
Ref. Figure 6
Ref. Figure 3
1
36
7
1
5
1
3
2
4
5
Ref. Figure 3
& Figure 4
Ref. Figure 6
Ref. Figure 7
Ref. Figure 7
Ref. Figure 7
Ref. Figure 7
Mar. 17
Property of American Airlines