Installation Procedure for Mounting Hydraulic Thumbs with Tool Bars{6547} Caterpillar

Engine:

G3406 (S/N: KAR1-UP)

Excavator:

330C (S/N: CYA1-UP; MCA1-UP; JAB1-UP; D3C1-UP; JCD1-UP; KDD1-UP; B1K1-UP; JNK1-UP; B2L1-UP; B3M1-UP; MKM1-UP; B4N1-UP; CAP1-UP; GKX1-UP; DKY1-UP)

330D (S/N: NBD1-UP; R2D1-UP; B6H1-UP; EAH1-UP; THJ1-UP; E4K1-UP; FFK1-UP; H3K1-UP; L2K1-UP; PEL1-UP; JJM1-UP; LRM1-UP; ERN1-UP; JLP1-UP; MWP1-UP; HAS1-UP; RAS1-UP; EDX1-UP; MEY1-UP; T2Y1-UP)

336D (S/N: JBF1-UP; J2F1-UP; PRF1-UP; LMG1-UP; MYG1-UP; KDJ1-UP; WRK1-UP; W3K1-UP; MPL1-UP; PPN1-UP; MYP1-UP; JWR1-UP; DTS1-UP; JBT1-UP; KKT1-UP; M4T1-UP; WET1-UP; PGW1-UP)

Thumb:

THUMB (S/N: 7JW1-UP)

Introduction

Special Instruction, REHS3899 is for field installation of hydraulic full rotation thumbs on Caterpillar Excavators.

The installation of the Caterpillar full rotation thumb is a complex procedure. This instruction must be followed as closely as possible in order to ensure the proper installation. Failure to follow the procedures outlined in this document may result in premature wear and failure of the hydraulic thumb.

If you require more information regarding the installation of the thumb please contact your local Caterpillar dealer.

Do not perform any procedure that is outlined in this publication and do not order any parts until you understand the information that is contained in this document.

Refer to your host machine and service literature for the work tool prior to performing this instruction.

Reference

• Reference Service Guide, SEBD0512, "Caterpillar Service Welding Guide"

• Reference Special Instruction, REHS1841, "General Welding Procedures"

• Reference Torque Specifications, SENR3130, "Torque Specifications for All Caterpillar Products"

• Reference Operation and Maintenance Manual, GEBJ0830

• Reference Thumb Ordering and Matching Guide, GEJQ0212

Welding Requirements

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Personal injury or death can result from fumes, gases and ultraviolet rays from the weld arc. Welding can cause fumes, burn skin and produce ultraviolet rays. Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing area. Wear eye, ear and body protection before working. Protect yourself and others; read and understand this warning. Fumes and gases can be dangerous to your health. Ultraviolet rays from the weld arc can injure eyes and burn skin. Electric shock can cause death. Read and understand the manufacturer's instructions and your employer's safety practices. Do not touch live electrical parts. See "American National Standard Z49.1, Safety in Welding and Cutting" published by the American Welding Society. American Welding Society 2501 N.W. 7th Street Miami, Florida 33125 See "OSHA Safety and Health Standards, 29 CFR 1910", available from U.S. Department of Labor. U.S. Department of Labor Washington, D.C. 20210

Welding quality is critical to the success of the installation procedures. Welds must be smooth and continuous. Do not undercut the welds. No overlap is allowed. Grind the ends of the welds to a smooth radius.

Prepare the metal for welding. Refer to ""Preparing the Metal for Welding" ". Refer to the illustrations in this Special Instruction for welding symbols and specifications.

Use AWS E7018 electrodes or equivalent electrodes to weld the guards to the work tool.

All electrodes must be dried. The electrodes can be dried by heating the electrodes to 300°C (572°F). The electrodes must be dried for at least 30 minutes.

Do not weld in windy conditions. Do not weld when temperatures are below 16°C (60°F).

Penetration characteristics may vary greatly depending on the following conditions:

• Electrode diameter

• Shielding gas

• Welding current

• Plate thickness

The following items also affect the welds:

• Geometry of welded joints

• Surface conditions

• Composition of the base metal and of the electrode

A root pass should be applied before each weld is finished.

Maintain a 3 mm (0.12 inch) minimum root opening on all cross welds and circle welds.

All welds to the stick must be welded in the direction from the rear of the stick toward the front of the stick.

For more welding information, consult the Caterpillar Service Welding Guide, SEBD0512.

Preparing the Metal for Welding

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Personal injury can result from flame cutting or welding on painted areas. The effect of gasses from burned paint is a hazard to the person doing the cutting or welding. Do not flame cut or weld on painted areas.

All grease, paint, and foreign objects must be removed before welding. Any of these materials will discharge gas which will cause porosity in the weld deposit. Water and rust will cause hydrogen embrittlement. Hydrogen embrittlement causes cracks in the weld deposit.

Remove foreign objects with a wire brush, a buffer, or a grinder. Shot blasting the appropriate areas will also remove foreign material.

Remove any oil or grease with a Caterpillar approved solvent.

Welding on Machines and Engines with Electronic Controls

Proper welding procedures are necessary in order to avoid damage to the electronic controls and to the bearings. The following steps should be followed in order to weld on a machine or an engine with electronic controls.

Note: If you are welding on a work tool, Caterpillar recommends removing the work tool from the host machine before welding.

1. Turn off the engine.

2. Turn the battery disconnect switch to the OFF position. If there is no battery disconnect switch, then remove the negative battery cable at the battery.

3. Clamp the ground cable from the welder to the component that will be welded. Place the clamp as close as possible to the weld. Make sure that the electrical path from the ground cable to the component does not go through any bearing. Use this procedure in order to reduce the possibility of damage to the following components:

• Bearings of the drive train

• Hydraulic components

• Electrical components

• Other components of the machine

Protect any wiring harnesses from the debris which is created from welding. Protect any wiring harnesses from the splatter which is created from welding.

Safety Section

General Hazard Information

Crushing Prevention and Cutting Prevention

Support the equipment properly before you perform any work or maintenance beneath the equipment. Do not depend on the hydraulic cylinders to hold up the equipment. Equipment can fall if a control is moved, or if a hydraulic line is broken.

Do not work beneath the cab of the machine unless the cab is properly supported.

Unless you are instructed otherwise, never attempt adjustments while the machine is moving or while the engine is running.

Never jump across the starter solenoid terminals in order to start the engine. Unexpected machine movement could result.

When a control linkage is present, the clearance in the linkage area will change with movement of the equipment or the machine. Stay clear of areas that may have a sudden change in clearance with machine movement or equipment movement.

Stay clear of all rotating and moving parts.

If it is necessary to remove guards in order to perform maintenance, always install the guards after the maintenance is performed.

Keep objects away from moving fan blades. The fan blade will throw objects or cut objects.

Do not use a kinked wire cable or a frayed wire cable. Wear gloves when you handle wire cables.

When you strike a retainer pin with force, the retainer pin can fly out. The loose retainer pin can injure personnel. Make sure that the area is clear of people when you strike the retainer pin. To avoid injury to your eyes, wear protective glasses when you strike a retainer pin.

Chips or other debris can fly off an object when you strike the object. Make sure that no one can be injured by flying debris before you strike any object.

Fluid Penetration

Pressure can be trapped in the hydraulic circuit long after the engine has been stopped. The pressure can cause hydraulic fluid or items such as pipe plugs to escape rapidly if the pressure is not relieved correctly.

Do not remove any hydraulic components or parts until pressure has been relieved or personal injury may occur. Do not disassemble any hydraulic components or parts until pressure has been relieved or personal injury may occur. Refer to the Service Manual of the host machine for any procedures that are required to relieve the hydraulic pressure.

Illustration 1	g00687600

Always use a board or cardboard when you check for a leak. Leaking fluid that is under pressure can penetrate body tissue. Fluid penetration can cause serious injury and possible death. A pin hole leak can cause severe injury. If fluid is injected into your skin, you must get treatment immediately. Seek treatment from a doctor that is familiar with this type of injury.

Lines, Tubes, and Hoses

Do not bend high-pressure lines. Do not strike high-pressure lines. Do not install any lines that are bent or damaged.

Repair any lines that are loose or damaged. Leaks can cause fires. Consult your Caterpillar dealer for repair or replacement parts.

Check lines, tubes, and hoses carefully. Do not use your bare hand to check leaks. Use a board or cardboard to check for leaks. Tighten all connections to the recommended torque.

Replace the parts if any of the following conditions are present:

• End fittings are damaged or leaking.

• Outer coverings are chafed or cut.

• Wires are exposed.

• Outer coverings are ballooning.

• Flexible part of the hoses is kinked.

• Outer covers have embedded armoring.

• The end fittings are displaced.

Make sure that all clamps, guards, and heat shields are installed correctly. During machine operation, doing this will help to prevent vibration, rubbing against other parts and excessive heat.

Installation Instructions

Illustration 2	g01766653
Excavator with a Full Rotation Thumb Installed. (A) Stick Pin (B) Replacement Bucket Idler Link (C) Idler Link Pin (D) Full Rotation Idler link (E) Integrated Stop (F) Power Link Mount (G) Cylinder Mounting Bracket (H) Tool Bar (I) Thumb Frame

Installation of the Hydraulic Pin Grabber for the Full Rotation Thumb

Installation of the Full Rotation Thumb Frame

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Personal injury or death can result from improper lifting or blocking. When a hoist or jack is used to lift any part or component, stand clear of the area. Be sure the hoist or jack has the correct capacity to lift a component. Install blocks or stands before performance of any work under a heavy component. Approximate weights of the components are shown. Clean all surfaces where parts are to be installed.

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Personal injury or death can result from sudden work tool movement. Sudden movement of the work tool can cause injury to persons near the work tool. To prevent injury or death, make sure that the area around the work tool is clear of personnel and obstructions before operating the work tool.

Ensure that the host machine is in park and is on a flat level surface.

1. Support the Work Tool properly.

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Illustration 3	g01766797
View

2. Remove the hydraulic cylinder, tool bar, idler link pin, and replacement bucket linkage from the thumb. Reassemble the linkage of the thumb without the cylinder.

3. Prepare the stick for welding of the thumb cylinder bracket. Refer to Table 1 for the approximate location of the cylinder bracket.

   Note: Do not install the thumb cylinder bracket at this time. Installation of the thumb cylinder bracket will take place later in the installation procedure.

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   Table 1

   Location that is Measured from the Center of the Stick Pin
   Part Number	Bracket
   309-9654	1667 mm (65.63 inch)
   318-1075	1665 mm (65.55 inch)

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Illustration 4	g01766958
Right Side View

4. Position the thumb underneath the boom of the excavator by using a suitable lifting device. Refer to Table 2 for the approximate weight of the thumb.

   Note: The Excavator boom will prevent an overhead lifting device from providing an adequate range of motion in order to position the thumb. It is a preferred practice to utilize a surface mounted lifting device, such as an engine hoist or a fork truck.

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   Table 2

   Weight of Thumb
   Part Number	Gross Weight	Frame Only
   309-9654	864 kg (1904 lb)	472 kg (1041 lb)
   318-1075	949 kg (2092 lb)	491 kg (1082 lb)

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Illustration 5	g01767362
Right Side View

5. Position the coupler so that the coupler rests on a flat, level surface. Ensure that the stick is positioned directly above the coupler. Also ensure that the stick exerts no down pressure on the coupler.

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Illustration 6	g01767514
Right Side View

6. Remove the main stick pin (1) from the stick and the coupler.

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Illustration 7	g01770215
Right Side View

7. Align the pin bores of the thumb with the pin bores of the stick and coupler.

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Illustration 8	g01770275

8. Center the thumb frame with the stick.

   Note: Do not use the bosses on the coupler as a guide. The bosses on the coupler may not be of equal thickness on both sides of the coupler.

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Illustration 9	g01770393
Left Side View (A) Stick Pin

9. Insert new stick pin (A) through the thumb, the coupler, and the stick. Utilize the correct number of shims on each side of the stick as listed in Table 3.

   Note: The shims in Table 3 are provided as a guide only. Proper alignment of the thumb may require a different configuration of shims.

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   Table 3

   Shims
   Thumb	Qty (Right Side)	Qty (Left Side)
   309-9654	2	2
   318-1075	11	1

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NOTICE
Ensure that the thumb frame is centered on the stick. There is a maximum allowable tolerance of 6 mm (0.24 inch). Failure to properly center the thumb frame will result in increased cylinder wear and premature failure.

10. Secure the stick pin.

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Illustration 10	g01770813
Left Side View

11. Lower the thumb to the surface the coupler is resting upon.

Installation of the Full Rotation Thumb Linkage

Illustration 11	g01770835
Left Side View

1. Remove the existing bucket idler link.

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Illustration 12	g01771014
Left Side View (B) Bucket Idler Link

2. Install bucket idler link (B). Secure the link at the bucket cylinder pin only.

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The linkage can move and form a pinch point which can cause personal injury. Keep hands away from the linkage.

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Illustration 13	g01772894
Left Side Idler

3. Slide pin (3) outward in order to allow right side idler link (D) to rotate independently. Do not remove pin (3) .

4. Using a suitable lifting device, raise the linkage of the thumb until left side idler link (D) can be positioned over the existing idler pin (2). Pin (2) may need moved inward to allow for idler link (D) to be positioned.

Note: Do not remove the lifting device until the installation of the thumb idler linkage is complete.

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Illustration 14	g01773473
Left Side View

5. Use new idler pin (C) to drive the old pin from the stick. Ensure pin (C) does not contact the right side bucket link. The pin must pass through the right side bucket link and idler link.

   Note: The left side and right side bucket links will need to be supported while installing pin (C) .

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Illustration 15	g01773414
Right Side View

6. Position right side idler link (D) as shown. Install pin (C) through the bore of right side idler link (D). Secure pin (C) using the retainer, bolt, and nuts provided.

7. Install and secure pin (3) through right side and left side idler links (D) .

Installation of the Hydraulic Cylinder

Illustration 16	g01773677
Curl of the Coupler

Illustration 17	g01773754
Thumb in Raised Position

1. Raise the thumb into the retracted position by rotating the coupler. Ensure that the thumb frame does not contact the sides of the coupler during rotation.

Note: The thumb frame is designed to provide clearance with the coupler, when the thumb frame is properly aligned. If interference occurs the thumb is not centered properly. Refer to the previous procedures to center the thumb.

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NOTICE
Do not allow the thumb frame to contact the sides of the coupler. Failure to prevent contact will result damage to the thumb and coupler.

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Illustration 18	g01773833
Left Side View

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The linkage can move and form a pinch point which can cause personal injury. Keep hands away from the linkage.

2. By using a suitable lifting device, position the cylinder along the stick and pin the cylinder to the thumb. Refer to Table 4for the weight of the cylinder.
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   Table 4

   Cylinder Weight
   Part Number of Thumb	Cylinder Part Number	Cylinder Weight
   309-9654	264-5128	152 kg (335 lb)
   318-1075	264-5128	152 kg (335 lb)

Note: Support the thumb idler links in order to prevent the links from falling.

3. Lower the cylinder to a resting position.

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Illustration 19	g01776353
Right Side View

4. Pin the cylinder mounting bracket (J) to the cylinder. Ensure that the hard line of the cylinder is located on the left side of the machine.

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Illustration 20	g01776453
Right Side View

5. Curl the stick into a position for transport. Ensure that the linkage guides (F) rest against the stick.

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NOTICE
If the linkage guides will not contact the stick because the integrated stop is contacting the thumb frame first, then material will need to be removed from the bottom of the integrated stop to allow the linkage guides to contact the stick.

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Illustration 21	g01776560
View of Area (AA)

6. Inspect the thumb frame in order to ensure that there is a minimum of 8 mm (0.31 inch) of clearance between the thumb frame opening and the stick (AA). Refer to Illustration 21.

7. Trim the thumb frame and grind the thumb frame smooth no more than 10 mm (0.40 inch) of material. Perform this task in order to obtain the desired 8 mm (0.31 inch) of clearance.

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NOTICE
There must be 8 mm (0.31 inch) to 10 mm (0.39 inch) of clearance between the thumb frame and the stick when the linkage guide is resting against the stick. Failure to provide this clearance could result in damage to the thumb frame or excavator stick.

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Check valves in the hydraulic system may allow pressure to exist in the hydraulic lines after the engine has been stopped. Pressure must be relieved prior to servicing the components of the hydraulic system. Failure to relieve pressure prior to servicing may result in personal injury.

8. Release the hydraulic system pressure.

   ReferenceRefer to your host machine service literature, Disassembly and Assembly, "Hydraulic System Pressure - Release" or Test and Adjust, "Hydraulic System Pressure - Release" for the correct procedure for releasing system pressure.

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NOTICE
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide"for tools and supplies to collect and contain fluids in Caterpillar machines. Dispose of all fluids according to local regulations.

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Illustration 22	g01776693
Right Side View

9. Attach auxiliary hoses to thumb cylinder.

10. Ensure that the hydraulic cylinder rod has 4.8 ± 1.6 mm (0.19 ± 0.06 inch) of stroke that is remaining in the cylinder. This is measured from the fully retracted position.

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Illustration 23	g01667106
Remaining Cylinder Stroke (L) Hydraulic Thumb Cylinder (M) 4.8 ± 1.6 mm (0.19 ± 0.06 inch)

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Personal injury can result from flame cutting or welding on painted areas. The effect of gasses from burned paint is a hazard to the person doing the cutting or welding. Do not flame cut or weld on painted areas.

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NOTICE
Before carrying out arc welding on the machine or any equipment attached to the machine, disconnect all power and ground leads from the batteries in order to avoid possible damage to electronic components.

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NOTICE
Before welding on the machine or any equipment attached to the machine, remove or cover any components with a suitable welding blanket that could be damaged by weld debris.

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Illustration 24	g01776739
Top View (Underside of Stick)

11. Position the mounting bracket on the stick directly in line with the center of the thumb frame and tack weld in place.

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NOTICE
Do not install the cylinder mounting bracket directly in the center of the stick without checking alignment of the thumb linkages. The cylinder mounting bracket must be installed directly in line with the thumb power link mount. This will ensure that linkages are properly aligned. Failure to align the linkages properly will result in increased cylinder wear and premature failure. Relocate the cylinder mounting bracket or thumb frame as necessary to ensure proper alignment of the linkages.

12. Slowly open and close the thumb four times to purge air from the system. Do not apply pressure to the thumb at this time. Ensure that the cylinder barrel does not contact the stick or any part of the thumb.

Adjustments to the Integrated Stop Linkage

Illustration 25	g01776796

1. Move the stick to the fully extended position. Ensure that the thumb hangs freely below the stick in order to remove any slack in the thumb linkage.

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Illustration 26	g01776873

2. Retract the cylinder until surface (B) contacts the bottom of the stick. Verify the cylinder barrel does not contact the stick or any part of the thumb.

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NOTICE
Do not allow the cylinder to contact the thumb frame or any part of the stick. Failure to prevent contact will result in damage to the cylinder, thumb frame, and stick.

3. Ensure surface (A) contacts the thumb frame and surface (B) contacts the stick simultaneously when the thumb is rotated into the fully retracted position.

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NOTICE
If the integrated stop does not contact the stick and thumb frame simultaneously, slight modifications will be required to ensure proper setup.

Note: If there is a gap between surface (A) of the integrated stop and thumb frame while surface (B) is contacting the stick, material will need to be added to surface (A) and/or the top thumb frame. Again, verify that the integrated stop contacts the thumb frame and stick simultaneously.

Note: If there is a gap between surface (B) and the bottom of the stick while surface (A) is contacting the thumb frame, material will need to be removed from surface (A). Again, verify that the integrated stop contacts the thumb frame and stick simultaneously.

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Illustration 27	g01776916
Left Side View

4. Install the tool bar with a suitable lifting device. The weight of the bar is approximately 90 kg (198 lb) to 300 kg (662 lb).

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Illustration 28	g01776932
Rear View

5. Install the matching bucket. Refer to the Operation and Maintenance Manual of your coupler for the proper coupling procedure.

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Illustration 29	g01777013
Left Side View

6. Position the bucket in the full dump position by retracting the bucket cylinder.

7. Slowly close the thumb until the cylinder is fully extended. Ensure that the teeth of the thumb rest are either between the bucket teeth or on top of the bucket teeth.

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NOTICE
If the teeth of the thumb interfere with the teeth of the bucket, the work tools may become lodged together and damage can occur.

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Illustration 30	g01777033

8. Carefully open the thumb until the cylinder is fully retracted. Ensure that the cylinder barrel does not contact the stick or any part of the thumb. Ensure the stop contacts the bottom of the stick and the top of the thumb frame simultaneously.

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NOTICE
Do not allow the cylinder to contact the thumb frame or any part of the stick. Failure to prevent contact will result in damage to the cylinder, thumb frame, and stick.

9. Remove the matching bucket. Refer to the Operation and Maintenance Manual of your coupler for the proper coupling procedure.

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Illustration 31	g01777160
Right Side View

10. Move the thumb to the fully open position and curl the stick into the transport position.

Setting Flows and Pressures

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Check valves in the hydraulic system may allow pressure to exist in the hydraulic lines after the engine has been stopped. Pressure must be relieved prior to servicing the components of the hydraulic system. Failure to relieve pressure prior to servicing may result in personal injury.

1. Release the hydraulic system pressure.

   ReferenceRefer to your host machine service literature, Disassembly and Assembly, "Hydraulic System Pressure - Release" or Test and Adjust, "Hydraulic System Pressure - Release" for the correct procedure for releasing system pressure.

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NOTICE
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide"for tools and supplies to collect and contain fluids in Caterpillar machines. Dispose of all fluids according to local regulations.

2. Disconnect auxiliary hydraulic connecting lines from the cylinder.

3. Test and adjust the maximum flows and pressures of the auxiliary hydraulic system, as needed. Refer to Table 5 at the end of this instruction.

Note: If the pressure and flows are not tested at this time it will be necessary to repeat the purging of air from the system.

Final Assembly

Illustration 32	g01777315
Right Side View

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The linkage can move and form a pinch point which can cause personal injury. Keep hands away from the linkage.

1. Remove the thumb cylinder from the mounting bracket.

   Note: Support the thumb idler links in order to prevent the links from falling.

2. Use a suitable lifting device in order to remove the thumb cylinder from the thumb. Refer to Table 4 for the weight of the cylinder.

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Illustration 33	g01777317
Right Side View

3. Use a suitable lifting device in order to raise the thumb linkage off the stick.

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Illustration 34	g01797783
View of Welded Bracket

4. Weld the bracket using a 12 mm (0.47 inch) fillet weld as shown. Do not weld across the stick.

5. Allow the welded area to cool. Prepare the welded area for the application of paint.

6. Apply a coat of rust prevention and a finish coat to the work area that has been completed. Use Caterpillar authorized paint.

7. Install the thumb cylinder by following the procedures listed above.

8. Connect the auxiliary hydraulic lines to the cylinder.

9. Tighten all fasteners to the proper torque specification.

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Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak.

10. Start the engine of the host machine. Cycle the hydraulic controls and check for leaks.

Requirements for the Thumb Circuit

The Caterpillar thumb is hydraulically operated through a three-position control valve. The center position blocks the cylinder ports. This maintains clamping force when the control valve is not actuated. Both working ports must be protected by a relief valve and a make-up check valve. This prevents damage to the thumb cylinder from excessive pressure.

The relief valves must be set at the provided flow and pressure settings, or at least a lesser value. Refer to Table 5 for the specified settings. This will allow the auxiliary hydraulic circuit to be over powered by the bucket circuit. The relief valves have the capacity in order to absorb 10 percent above the supplied auxiliary circuit flow. Make-up (anticavitation) check valves should allow the bucket to displace the thumb without causing cavitation on the rod side of the thumb cylinder.

Illustration 35	g01677215
Circuit Requirement (N) Pressure (P) Return (Q) Tank

Note: Flow and pressure settings shown in the above table reflect both pin on and pin grabber coupler style Full Rotation Thumbs.