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Introduction
This Special Instruction contains procedure to replace drive assembly of starter motor on all Cat products.
Do not perform any procedure in this Special Instruction until you have read the information and you understand the information.
Safety Section
The information, specifications, and illustrations in this publication are based on information that was available at the time that the publication was written. 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 and most current information before you start any job. Cat dealers have the most current information available.
Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools to perform these functions properly.
Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard.
Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. If the tools, the procedure, the work method, or your actions are not recommended by Caterpillar, ensure that the tools and your actions are safe for you and for others.
Ensure that all personnel are safe when using a tool, procedure, work method, or operating technique not recommended by Caterpillar. Ensure that the product will not be damaged or the product made unsafe by the operation, lubrication, maintenance, or the repair procedures that are used.
Note: Always use proper eye protection when performing any mechanical repairs to a vehicle and any installation or repairs to starting motors. Failure to use proper eye protection can lead to serious and permanent eye damage.
Do not operate or work on this product unless you have read and understood the instruction and warnings in the relevant Operation and Maintenance Manuals and relevant service literature. Failure to follow the instructions or heed the warnings could result in injury or death. Proper care is your responsibility. |
Failure to follow all safety guidelines prescribed in this document and by governing authorities and regulatory agencies may result in severe injury or death of personnel or machine damage. |
When removing a major component or attachment, ensure that it is properly blocked or secured before removing mounting hardware. An assembly that is disconnected without proper blocking may shift or fall, resulting in serious injury or death of personnel or machine damage. |
Personal injury or death can result from improper maintenance procedures. To avoid injury or death, follow the procedures exactly as stated below. |
Personal injury can result from improper handling of chemicals. Make sure you use all the necessary protective equipment required to do the job. Make sure that you read and understand all directions and hazards described on the labels and material safety data sheet of any chemical that is used. Observe all safety precautions recommended by the chemical manufacturer for handling, storage, and disposal of chemicals. |
Before servicing/performing maintenance on the machine, electrical power must be physically disconnected; battery plugs must be disconnected from the batteries, or the trailing cable must be unplugged, and warning tags and padlocks shall be applied by a certified electrician. Certified electricians shall perform or direct any electrical work, including any energized testing, repair work in controllers, motors, or other approved compartments, and shall insure that all compartments are properly closed and inspected prior to re-energization. All applicable lock out and tag out procedures must be followed. |
Do not operate the machine if any guards or covers are missing or inadequately secured. Personnel could be seriously injured or machine damage may occur. |
Observe the safe working load limits of all lifting and blocking devices and keep a safe distance from suspended/blocked loads. Personnel may be seriously injured or killed by falling loads. |
Machine Preparation
- Move the machine to a level surface.
- Apply parking brake. Turn engine key switch to OFF position.
Show/hide table
Illustration 1 g00104545 - Perform Lockout Tag Out procedure by attaching a warning tag to the machine controls.
Replacement Procedure
Note: If your starter motor part number is listed in Table 1, refer to Illustration 2 for pinion adjustment.
Note: If your starter motor part number is listed in Table 2, refer to Illustration 2 for pinion adjustment.
Note: If your starter motor part number is listed in Table 1 and Table 2, refer to Illustration 2 for pinion adjustment.
List of Starter Motor Part Numbers Referring to Illustration 2. | |
---|---|
Part Number | Part Name |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp |
List of Starter Motor Part Numbers referring to Illustration 2. | |
---|---|
Part Numbers | Part Name |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp | |
Electric Starting Motor Gp |
Illustration 2 | g06421595 |
(A) Plug hole
(B) Shaft nut (C) Drive (E) Pinion |
Illustration 3 | g06421549 |
(D1) (E) Pinion |
Illustration 4 | g06421554 |
(D2) (E) Pinion |
Illustration 5 | g06421571 |
(D3) (E) Pinion |
Disassembly
Note: Before starting to disassembly the starting motor, disconnect the battery ground before removing or replacing cables at the starter motor. Failure to disconnect the battery ground cable can lead to serious injury.
- Remove vehicle leads connected to the starter, noting their positions for reinstallation of starter, and remove starter.
- Mark the drive and lever housings positions for mounting it again.
- Remove field coil connector strap and solenoid ground lead from the solenoid.
- Remove the access plug and gasket from front of lever housing, ensuring gasket is removed.
- Remove six drive housing mounting bolts and the drive housing.
- Remove five lever housing mounting bolts.
- Remove the lever housing, solenoid and drive assembly as a unit. For starter motors listed in Table 1, it is necessary to remove the pinion stop and retaining ring from the armature shaft in order to release the drive assembly from the armature. NOTE! The armature’s retaining ring must be replaced with a new one in order to avoid a potential premature motor failure.
- Remove the drive assembly from the lever housing.
- If replacing the brake washer, it is available in universal service package. Itis recommended to replace the brake washer depending on usage. It can be stuck on either the drive or lever housing to assemble.
Assembly
- Install the lever housing, solenoid and drive assemblies, noting alignment marks. Insert shift lever yoke into the drive assembly collar during installation. Install five mounting screws and torque to
16.3 to 22.0 N·m (144 to 194 lb in) . For starter motors listed in Table 1, install a new retaining ring into the armature shaft groove and replace the pinion stop. - Apply a small amount of SAE20 oil into the drive housing bushing and install the drive housing assembly, aligning the marks. Install and torque six mounting bolts to
17.63 to 29.8 N·m (156 to 263 lb in) . - Replace ground lead to solenoid ground terminal and torque nut to
1.8 to 4.3 N·m (15 to 38 lb in) .Note: Do not reconnect solenoid motor connector strap to field terminal before adjusting the pinion clearance.
Note: After repair and assembly, it is necessary to check and adjust pinion clearance before installation of engine.
Note: Proper care must be exercised when completing these steps to avoid personal injury or other property damage. Do not apply power in excess of one minute to avoid over heating and possible damage to the solenoid.
- Follow Step 4a through Step 4f carefully to adjust the pinion clearance.
- Ensure the stamped metal connector strap is disconnected from the field terminal to prevent the possibility of motor from rotating.
- Energize solenoid to prevent plunger from rotating and damaging the rubber boot while turning plunger nut to adjust pinion clearance.
- Apply appropriate power (12V or 24V) to solenoid between the switch "S" (+) and “G” ground (-) terminals.
- Seat the plunger by simultaneously pushing on 1/2" plunger nut.
Note: 24 V can be obtained by connecting two 12 V batteries in series.
- Adjust plunger nut to obtain the pinion clearance defined based on the motor series being worked on.
- Remove power immediately after adjustment is completed.
- Reinstall access plug and gasket in front of the lever housing and torque plug to a minimum of
8.1 N·m (72 lb in) . - Reinstall solenoid-to-motor field connector strap.
- Reinstall field terminal and solenoid motor terminal screws finger tight.
- Torque field terminal and solenoid motor terminal screws to
8.5 to 10.7 N·m (75 to 95 lb in) . - For insulated models, remove the nut and washer assembly from solenoid ground terminal and install the flex ground lead.
- Install ground terminal nut and washer assembly and tighten to
1.8 to 4.3 N·m (16 to 38 lb in) . - Reinstall starter and connect cables and other leads, as removed.
- Reconnect the negative (-) terminal to the battery.