BLOCK-CYL 6N7986 - Caterpillar

Disassembly Procedure
Personal injury can result from failure to disconnect the battery.First, disconnect the negative battery cable. Then, disconnect the positive battery cable.A positive power lead can cause sparks if the battery is not disconnected. Sparks can possibly result in battery explosion or fire.
Use the following procedure to disassemble brush plate from the starting motor:
Remove vehicle leads connected to the starter, noting positions for reinstallation of starter, and remove starter.
Remove the solenoid lead from the ground stud in the CE housing, noting position of the ground stud or mark the CE housing & frame for reassembly.
Remove the six CE screws.
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Remove the three plugs from the frame to allow removing the three field leads to positive brushes attaching screws for 12V, 24V & 32V models or two field leads to positive brushes attaching screws for 64V models.
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Remove the CE housing and armature assembly as a unit. It is best to remove them together to keep the brushes contained.
If only replacing the brushes, remove the remaining brush screws and contain in that position with the brush springs to release the armature. Go to step 5 in assembly procedures.
From the insulated/ground terminal, carefully noting orientation for reassembly, remove all remaining hardware. Check the condition of insulators and sealing features and consider replacing. If insulators and sealing are damaged or excessively worn.
Remove the three brush plate to CE housing attaching screws and remove brush plate.Cleaning Procedure
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Use the following procedure to clean electric starting motor brush:
It is recommended that the brush plate assembly and CE frame be separated for a thorough cleaning, being careful not to damage the aramid paper (white) insulator or grommet for the insulated/ground terminal.Note: Do not use air pressure to remove dust from inside the frame.
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Using a low-pressure source of air, blow the brush dust out of CE frame and the brush assembly. It may be necessary to use a screw driver or similar device to remove all the carbon (hardened brush dust).
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It may also be necessary to scrape the hardened dust from the four recessed holes that are on the back side of the brush holder assembly. These recessed holes are for the threaded ends of the ground brush holders.
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Thoroughly examine the brush plate for chunks of hardened brush dust that could become grounded and carefully remove. The fiber insulators at the base of the insulated brush holders are an area that may need some cleaning. Remove the hardened brush dust all around the outside edge of these insulators.
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Any cleaning inside the frame should be done with a nylon brush or cloth.Assembly Procedure
Use the following procedure to assemble brush plate to starting motor:
Place the insulator paper in between brush-plate assembly and the CE housing.
Place the two insulator washers and rubber bushing on the ground stud at the brush-plate.
Attach the brush-plate assembly to the insulator paper on the CE with the three attaching screws. Torque the screws to 1.92 to 3.95