- Off-Highway Truck:
- 777D (S/N: FKR1-UP)
Introduction
The following Special Instruction contains the necessary instructions for upgrading the 175-0183 Support Assembly on the 777D Off-Highway Truck. The 388-4702 Reinforcement Plate Gp Kit is required for this procedure.
ReferenceSpecial Instruction, REHS1841, "General Welding Procedures"
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Do not operate or work on this machine unless you have read and understand the instructions and warnings in the Operation and Maintenance Manuals. Failure to follow the instructions or heed the warnings could result in injury or death. Contact your Cat dealer for replacement manuals. Proper care is your responsibility. |
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Accidental engine starting can cause injury or death to personnel working on the equipment. To avoid accidental engine starting, disconnect the battery cable from the negative (−) battery terminal. Completely tape all metal surfaces of the disconnected battery cable end in order to prevent contact with other metal surfaces which could activate the engine electrical system. Place a Do Not Operate tag at the Start/Stop switch location to inform personnel that the equipment is being worked on. |
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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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| NOTICE |
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Keep all parts clean from contaminants. Contaminants may cause rapid wear and shortened component life. |
Required Parts
| Parts List for 388-4702 Reinforcement Plate Gp Kit | ||
| Qty | Part Number | Description |
| 1 | 368-9948 | Plate |
| 1 | 368-9950 | Plate |
| 3 | 368-9951 | Plate |
| 10 | 5P-2566 | Bolt |
| 10 | 8T-7971 | Hard Washer |
Important Safety Information
Follow all safety warnings. Most accidents that involve product operation, maintenance, or repair are caused by failure to observe safety warnings. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. Personnel should be properly trained in order to perform maintenance, repair, or operate any machine. Safety precautions and warnings are provided this instruction and on Caterpillar products. These warnings should be observed before performing any procedures. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. The warnings in this publication and on the product are not all inclusive.
The hazards are identified by the "Safety Alert Symbol" which is followed by a "Signal Word" such as "DANGER", "WARNING" or "CAUTION". The "WARNING" Safety Alert Symbol is shown in Illustration 1.
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| Illustration 1 | g00008666 |
This safety alert symbol means:
Pay Attention!
Become Alert!
Your Safety is Involved.
The message that appears under the safety alert symbol explains the hazard.
Operations that may cause product damage are identified by "NOTICE" labels on the product and in this publication.
The information, the specifications, and the illustrations that exist in this guideline are based on information which was available at the time of publication. The specifications, torques, pressures, measurements, adjustments, illustrations, and other items can change at any time. These changes can affect the service that is given to the product. Obtain the complete, most current information before you start any job. Caterpillar dealers can supply the most current information.
Basic Precautions
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Improper operation, lubrication, maintenance or repair of this product can be dangerous and could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information. |
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Always observe the list of basic precautions that follows:
Safety Signs
Safety signs include the items that follow: signs, information plates and decals. Read all "Safety" signs on the machine before operating, lubricating, or repairing the machine. Understand all "Safety" signs on the machine before operating, lubricating, or repairing the machine. Replace any safety signs that are in the conditions that follow: damage, unreadable and missing.
Protective Equipment
When you are welding, use the appropriate protective equipment that is required by the job conditions. Protective equipment for welding includes the items that follow: gloves, welding hood, goggles and apron. Do not wear loose clothing or jewelry that can catch on parts of the machine.
Specifications for Cables, Chains, and Lifting Devices
Use approved cables, chains, and lifting devices in order to lift components. Refer to the manufacturer's weight's in order to determine the application when you select the following items: cable, chain and lifting devices. When you lift a component, the lift angle is critical. Refer to the Illustration that follows in order to see the effect of the lift angle on the working load limit.
Note: The lifting devices that are shown in this publication are not Caterpillar parts.
Note: Ensure that the hooks are equipped with a safety latch. Do not place a side load on the lifting eyes during a lifting operation.
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| Illustration 2 | g00629745 |
Lift angles for lifting slings. (A) The load capacity is 100% of the working load limit for the sling. (B) The load capacity is 86% of the working load limit for the sling. (C) The load capacity is 70% of the working load limit for the sling. (D) The load capacity is 50% of the working load limit for the sling. | |
Machine Preparation
- Move the machine to a hard level surface.
- Avoid sudden steering inputs when you are parking the machine.
- Apply the service brakes in order to stop the machine.
- Move the transmission control lever to the NEUTRAL position.
- Move the parking brake switch rearward to the ON position in order to engage the parking brake.
- If the body is fully lowered, place the hoist control lever in the FLOAT position for at least 10 seconds.
- If the body is in the raised position, ensure that all of the body pins have been installed correctly, or that the retaining cable has been installed correctly. Refer to Operation and Maintenance Manual, "Body Retaining Pins - Installation", or Operation and Maintenance Manual, "Cable (Truck Body Retaining) - Installation" for instructions on securing the truck body. Place the hoist control lever in the FLOAT position for at least 10 seconds.
- Turn the engine start switch to the OFF position in order to stop the engine.
- Turn the battery disconnect switch to the OFF position.
- Disconnect the battery. Refer to Special Instruction, SEHS7633, "Battery Maintenance Procedure" for additional information on the battery.
- Chock the front wheels and the rear wheels. Refer to Disassembly and Assembly, "Wheel Chock (Front and Rear) - Remove and Install".
Welding Qualifications and Preparation
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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 kill. Read and understand the manufacturer's instruction and your employer's safety practices. Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing zone and the general area. Wear correct eye, ear and body protection. Do not touch live electric parts. Refer to the American National Standard Z49.1, "Safety in Welding and Cutting" published by the American Welding Society, 2501 N.W. 7th Street, Miami, Florida 33125: OSHA Safety and Health Standards, 29 CFR 1910, available from U.S. Dept. of Labor, Washington D.C. 20210. |
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Note: Personal breathing protection should be worn by the personnel that are welding. Personal breathing protection will prevent fumes from entering the lungs of the person that is welding. Use a 237-5181 Respirator for breathing protection.
Qualifications
Welders must be qualified for the appropriate type of weld that is being performed. Welders must be qualified for the appropriate position of weld that is being performed. Welders must be qualified for the welding process that is being utilized: Shielded Metal Arc Welding (SMAW), Flux Cored Arc Welding (FCAW) and Gas Metal Arc Welding (GMAW). Refer to AWS Specifications D1.1 and D14.3 or comparable standards for information that regards qualification requirements. The welders must have used the process at some time within the last six months. The welders must complete the process of certification if the welders have not used the welding processes for six months.
Area Preparation
The area to be welded shall be clean, dry, and free of the following contaminants:
- Oil
- Grease
- Paint
- Dirt
- Rust
- Any fluids or moisture
All welding shall be conducted on base material heated and maintained at a minimum temperature of 15.6° C (60° F).
Note: Heating instructions (preheat, interpass, and postheat) for any specific repair shall override the minimum 15.6° C (60° F) requirement.
Note: Heat distortion of the base metal is possible when you weld. Avoid excessive heating of the base metal.
Attach the welding ground cable directly to the base metal. Protect machined surfaces from sparks. Protect the machined surfaces from the welding spatter.
Welding Electrodes and Parameters
Flux Cored Welding Electrode for the FCAW Process
Use the Flux Cored Arc Welding (FCAW) with E71T-1 H8 (ANSI/A5.20) welding electrode and the manufacturer's shielding gases that are specified (typically 75% argon and 25% carbon dioxide). The H8 implies that the electrode is designed to provide less than 8 ml/100 g of diffusible hydrogen in the weld deposit. The weld that is deposited by the flux cored welding electrode will have the following minimum mechanical properties:
| Mechanical Properties from Flux Cored Welding Electrode That Is Classified as "ANSI/AWS A5.20 E71T-1 H8" | |
|---|---|
| Tensile Strength | 480 MPa (70000 psi) |
| Yield Strength | 400 MPa (58000 psi) |
| Elongation | 22% |
| Impact Toughness | 27 J @ -18 °C (20 ft lb @ -0 °F) |
The tables that follow show the recommended parameter ranges for out of position welding in the field for two different flux cored welding electrode diameters.
| Welding Current for Flux Cored Welding Electrode that Is 1.2 mm (0.045 inch) |
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| Wire Feed Rate | Voltage | Amperage |
7620 mm (300 inch) Per Minute to 10,160 mm (400 inch) Per Minute |
24 to 28 | 190 to 240 |
| Welding Current for Flux Cored Welding Electrode that Is 1.4 mm (0.052 inch) |
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| Wire Feed Rate | Voltage | Amperage |
5080 mm (200 inch) Per Minute to 6350 mm (250 inch) Per Minute |
23 to 27 | 180 to 220 |
Note: The settings listed above are recommendations-based on our experience for welding in the horizontal, vertical-up, and overhead positions. Slight changes in the voltage and amperage may be necessary due to welding position and various formulations by different electrode manufacturers. It is acceptable to use higher parameters than specified for welding in the flat position.
Use a polarity setting of DC reverse polarity. Remove the slag after each pass of the welding electrode. The fast freezing characteristics of flux cored welding electrode increases the possibility of evolving gas that is trapped in the weld. Control the size of the weld in order to reduce the possibility of evolving gas that is trapped in the weld. The maximum size weld per pass should be equivalent to that of a 8.0 mm (.32 inch) fillet weld.
Low Hydrogen Electrodes for the SMAW Process
As an alternative process or when wind conditions are a factor, use SMAW and low hydrogen electrodes that meet the following requirements.
| Mechanical Properties of Welds from Low Hydrogen Electrodes That Are Classified as "ANSI/AWS A5.1 E7018" | |
|---|---|
| Tensile Strength | 480 MPa (70000 psi) |
| Yield Strength | 400 MPa (58000 psi) |
| Elongation | 22% |
| Impact Toughness | 27 J @ -29 °C (20 ft lb @ -20 °F) |
Low hydrogen electrodes must be stored in an electrode oven at 120 °C (250 °F). If low hydrogen electrodes get damp, scrap the low hydrogen electrodes or recondition the low hydrogen electrodes to the manufacturer's specifications.
The table that follows shows the settings for the welding current based on electrode diameter.
| Welding Current for Low Hydrogen Electrodes | |
|---|---|
| Diameter | Amperage Rating |
| 3.2 mm (1/8 inch) | 105-155 |
| 4.0 mm (5/32 inch) | 130-200 |
| 4.8 mm (3/16 inch) | 200-275 |
Use a polarity setting of DC reverse polarity. Remove the slag after each pass of the welding electrode. The width of the weld should not exceed two times the electrode diameter.
Arc Welding Electrodes for the GMAW Process
The table that follows lists the mechanical properties of welds that are deposited by the GMAW Process.
| Mechanical Properties of Welds from Gas Metal Arc Welding Electrodes That Are Classified as "ANSI/AWS A5.18 ER70S-6" | |
|---|---|
| Tensile Strength | 480MPa (70,000 psi) |
| Yield Strength | 400 MPa (58,000 psi) |
| Elongation | 22% |
| Impact Toughness | 27J @ -30 °C (20 ft lb @ -20 °F) |
Required Parts
| Parts List for 388-4702 Reinforcement Plate Gp Kit | |||
| Item | Qty | Part Number | Description |
| 1 | 1 | 368-9948 | Plate |
| 2 | 1 | 368-9950 | Plate |
| 3 | 3 | 368-9951 | Plate |
| 4 | 10 | 5P-2566 | Bolt |
| 5 | 10 | 8T-7971 | Hard Washer |
Removal Procedure
Remove the Mirror Group
- Remove mirror group (A). Retain mirror group (A) and mounting hardware.
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| Illustration 3 | g03194437 |
View of the front right-hand side (A) Mirror group (B) Signal and head lamps | |
- Disconnect the wire harnesses from the signal and head lamps (B) .
Remove the Muffler Group (If Equipped)
- Attach a suitable lifting device to muffler group (C). The approximate weight of muffler group (C) is 90 kg (200 lb).
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| Illustration 4 | g03195716 |
View of the front right-hand side (C) Muffler group | |
- Remove muffler group (C). Retain muffler group (C) and mounting hardware.
Remove the Support Assembly
- Attach a suitable lifting device to support assembly (D). The approximate weight of support assembly (D) is 225 kg (500 lb).
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| Illustration 5 | g03196076 |
Bottom view of the right-hand side support assembly (D) Support assembly | |
- Remove the 20 bolts and hard washers securing the support assembly (D) and remove support assembly (D). Retain bolts and hard washers except for the ten bolts and hard washers from the area highlighted in Illustration 5. The addition of the support plates will require longer bolts for this area.
- Position support assembly (D) so that the areas highlighted in Illustration 6 can be easily accessed and welded.
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| Illustration 6 | g03196164 |
Bottom view of the right-hand side support assembly | |
Rework Procedure
| Weld Specifications | |
| Item | Description |
| W1 | 3 mm (0.12inch) fillet weld 25 mm (1.00 inch) long on 75 mm (3.0 inch) center |
| W2 | 3 mm (0.12inch) fillet weld 25 mm (1.00 inch) long on 75 mm (3.0 inch) center |
| W3 | 3 mm (0.12inch) fillet weld 25 mm (1.00 inch) long on 75 mm (3.0 inch) center |
Remove Cracks
- Apply dye penetrant in order to check the length of the crack.
- Excavate the crack by gouging or grinding to sound metal.
- Ensure that the crack is removed by applying dye penetrant.
Install the Plates onto the Support Assembly
- Clean the area to be welded.
- Position plate (1), plate (2) and plates (3) onto support assembly (D) as shown in Illustration 7.
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| Illustration 7 | g03200176 |
Bottom view of the right-hand side support assembly (1) Plate (2) Plate (3) Plate | |
- Use the welds shown in Illustration 8 in order to secure the plates onto support assembly (D) .
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| Illustration 8 | g03200716 |
Bottom view of the right-hand side support assembly (W1) 3 mm (0.12inch) fillet weld 25 mm (1.00 inch) long on 75 mm (3.0 inch) center (W2) 3 mm (0.12inch) fillet weld 25 mm (1.00 inch) long on 75 mm (3.0 inch) center (W3) 3 mm (0.12inch) fillet weld 25 mm (1.00 inch) long on 75 mm (3.0 inch) center 3 plates | |
- Inspect the welds ensuring that the welds are free from cracks, porosity, undercut, and incomplete fusion.
- Paint support assembly (D) as needed.
Install the Support Assembly
- Attach a suitable lifting device to support assembly (D). The approximate weight of support assembly (D) is 225 kg (500 lb).
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| Illustration 9 | g03201733 |
Bottom view of the right-hand side support assembly (D) Support assembly (4) Bolt (5) Hard washer | |
- Install support assembly (D). Secure support assembly (D) using 10 bolts (4), 10 hard washers (5), and the bolts and hard washers retained in Step 2 of the ""Remove the Support Assembly" ".
Install the Muffler Group (If Equipped)
- Attach a suitable lifting device to muffler group (C). The approximate weight of muffler group (C) is 90 kg (200 lb).
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| Illustration 10 | g03195716 |
View of the front right-hand side (C) Muffler group | |
- Install muffler group (C). Secure muffler group (C) using the hardware retained in Step 2 of the ""Removal Procedure" ".
Install the Mirror Group
- Install mirror group (A). Secure mirror group (A) using the hardware retained in Step 1 of the ""Removal Procedure" ".
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| Illustration 11 | g03194437 |
View of the front right-hand side (A) Mirror group (B) Signal and head lamps | |
- Connect the wire harnesses from the signal and head lamps (B) .
Register the Retrofit
- When performing a retrofit installation, record the vital information in Table 10.
Note: If the procedure is performed by the customer, ask the customer to record the proper information.
Show/hide tableTable 10 Repair Date Product Serial Number Service Hours or Service Meter Units Removed Component Part Number (1) Removed Component Serial Number (1) Installed Component Part Number (2) Installed Component Serial Number (3) Show/hide table( 1 ) Only applies if a component is replaced by a retrofit component. If the product is an engine, and the product retrofit is a kit for upgrading the engine, disregard the "Removed Component" information. Refer to detailed instructions in Step 3 for more information. ( 2 ) Record the highest level retrofit kit, arrangement, or group part number. ( 3 ) Most retrofits will not have a serial number. Exceptions include emissions repower engines and diesel particulate filters.
- Update the product configuration by entering the information from Table 10 into SIMSi and AIMS.
Note: For retrofits that have a Caterpillar serial number, the AIMS application is "JIZ111-08". For retrofits that do not have a Caterpillar serial number, the AIMS application is "JIZ111-07".
- For detailed instructions on updating the product configuration, refer to Special Instruction, REHS5097, "Instructions to Register the Retrofit".