Cadillac 10465394 Motor Asm,Start (Remanufacture) Sd200

To remove and install the starter, begin by disconnecting the negative battery cable and raising the car on jackstands. Remove any starter braces or shields in the way, then remove the starter motor-to-engine bolts and allow the starter to drop down. Disconnect the solenoid wires and battery cable before removing the starter. To replace the solenoid, remove the starter from the vehicle and remove the screw and washer from the motor connector strap terminal. Remove the screws retaining the solenoid housing to the end frame assembly and twist the solenoid clockwise to remove the flange key from the keyway slot. Remove the solenoid assembly and install the new one by positioning the solenoid body on the drive housing and turning it counterclockwise to engage the flange key in the keyway slot. Install the screws to retain the solenoid housing to the end frame. For an overhaul, start by removing the starter from the vehicle and disconnecting the field coil straps from the solenoid. Remove the through-bolts to separate the commutator end frame, field frame assembly, drive housing, and armature assembly. On diesel starters, remove the insulator from the end frame and the shift lever pivot bolt. On 25 MT diesel starters, remove the center bearing screws and the drive gear housing from the armature shaft. Slide off the 2-piece thrust collar from the armature shaft and use a piece of pipe or socket to drive the retainer toward the snapring. Remove the snapring with pliers and slide off the retainer and starter drive. To reinstall, lubricate the armature shaft and install the starter drive and retainer. Place the snapring on the shaft and tap it into place. Slide the retainer and thrust collar onto the shaft and squeeze them together with pliers. Lubricate the drive housing bushing and engage the shift lever yoke with the clutch. Install the drive assembly into the drive gear housing and reassemble the remaining components. For brush replacement, disconnect the field coil from the motor solenoid terminal and remove the starter through bolts. Remove the commutator end frame and washer, then remove the field frame and armature assembly from the drive housing. Remove the brush holder pivot pin, brush springs, and brushes. Install the new brushes and reassemble the components in reverse order.

To remove and install the starter, start by disconnecting the ground cable from the battery. Then, raise the vehicle and support it with jack stands. Next, disconnect the leads at the starter solenoid, marking each with coded tape for easy identification later. Temporarily refit the securing nuts to the terminals. Remove the bolts securing the plastic starter shield and slide it back to expose the starter mounting bolts. Take out the starter to engine brace and then remove the two starter motor mounting bolts. Finally, remove the starter. To reinstall, follow the reverse order of removal, tightening the mount bolts first to the specified torque and then tightening the front bracket bolt and nut. Make sure to replace any shims that were removed for proper alignment. Refit the wires to the solenoid terminals using the identification coding.

Please be aware that the disassembly and testing of the starter motor are critical processes, and it might be advisable for the home mechanic to consider purchasing a new or factory-rebuilt unit instead. However, if the decision is made to overhaul the starter, check the availability of singular replacement components before proceeding. To begin, disconnect the starter motor field coil connectors from the solenoid terminals and unscrew and remove the through bolts. Next, remove the commutator end frame, field frame assembly, and the armature from the drive housing, along with the solenoid and shift lever assembly. Slide the two-section thrust collar off the armature shaft and expose the snap-ring by driving the stop/retainer up the armature shaft using a suitable tube. Extract the snap-ring from its shaft groove and slide the stop/retainer and overrunning clutch assembly from the armature shaft. Proceed to dismantle the brush components from the field frame and release the V-shaped springs from the brushholder supports. Remove the brushholder support pin and lift the complete brush assembly upwards. If the brushes are worn down to half their original length and need replacement, disconnect the leads from the brushes. The starter motor is now completely dismantled, except for the field coils. If the field coils are found to be defective during the tests described later, the removal of the pole shoe screws should be done at a service station with the necessary pressure driver. Clean all components and replace any obviously worn ones. Note that roller-type clutches should not be disassembled and are serviced as complete units. Under no circumstances should the insulation between the commutator segments on molded type commutators be undercut. However, on conventional commutators, undercut the insulation by in using an old hacksaw blade, ensuring the groove is square at the bottom. Once undercutting is complete, brush away all dirt and dust. Clean the commutator by spinning it with number '00' sandpaper wrapped around it (do not use any other abrasive material). If the commutator is severely damaged, it may be turned down in a lathe to provide a new surface, but make sure to undercut the insulation after turning. To test the armature for ground, use a lamp-type circuit tester by placing one lead on the armature core or shaft and the other on a commutator segment. If the lamp lights up, the armature is grounded and needs replacement. To test the field coils for an open circuit, place one test probe on the insulated brush and the other on the field connector bar. If the lamp does not light, the coils are open and must be renewed. To test the field coils for ground, place one test probe on the connector bar and the other on the grounded bush. If the lamp lights up, the field coils are grounded. Finally, remember that the overrunning clutch cannot be repaired, and if it is faulty, it must be replaced as a complete assembly.

Ensure that the speed selector lever is in 'N' or 'P' for automatic transaxle or that the clutch pedal is depressed for manual transaxle if the starter motor does not rotate when operated. Verify that the battery is charged and all cables, at both the battery and starter solenoid terminals, are secure. If the motor can be heard spinning but the engine isn't cranked, the overrunning clutch in the starter motor is likely slipping, requiring removal and dismantling. If the starter motor doesn't operate, but a loud 'click' is heard from the solenoid plunger, the fault lies in the main solenoid contacts or the starter motor itself. In cases where the solenoid plunger doesn't move, the solenoid may be defective or the solenoid circuit open. You can check the solenoid by connecting a jumper lead between the battery (+) and the 'S' terminal on the solenoid. If the starter motor operates, the fault lies in the ignition or neutral start switches or their interconnecting wiring. If it doesn't, the starter/solenoid assembly should be removed for testing and repair. If the engine cranks at an unusually slow speed, check the battery charge and terminal connections, oil grade, and ensure no mechanical fault within the power unit. Run the engine to normal operating temperature, disconnect the battery feed wire to the distributor cap to prevent engine firing during cranking, then connect a voltmeter positive lead to the starter motor terminal of the solenoid and the negative lead to ground. Ignite the switch, take the voltmeter readings once steady, but don't let the starter motor turn for more than 30 seconds at a time. A reading of 9 volts or more with normal cranking speed indicates a good condition, while the same voltage but slow cranking speed denotes a faulty motor. A reading of less than 9 volts with slow cranking speed suggests the solenoid contacts are likely at fault and should be replaced.

Disconnect the negative battery cable. Raise the rear of the vehicle and support it securely on jackstands. Block the front wheels. Remove the catalytic converter splash shield. From under the vehicle, disconnect the solenoid wire and battery cable from the terminals on the rear of the solenoid. Remove the support bracket, if equipped, and retaining bolts. Remove the starter. Note the location of the spacer shim. Place the starter in position. Install the spacer shim. Install the support bracket, if equipped, and tighten the starter mounting bolts. Attach the solenoid wire and battery cable to the terminals on the rear of the solenoid. Lower the vehicle. Connect the negative battery cable.

Ensure that the battery is fully charged before diagnosing starter problems. In case the switch is operated and the starter does not turn, make sure the shift lever is in Neutral or Park (automatic transmission) or that you depress the clutch pedal (manual transmission). Check that your battery is charged and all cables are secure. This could mean a slipping overrunning clutch in the starter, which can call for removal and disassembly of the starter. It could be with your battery, main solenoid contacts or even the starter itself if solenoid clicks but there is no operation on the starter. It may be defective if you can't hear solenoid plunger when switch is actuated, this could be due to defective solenoid or solenoid circuit. Attach a jumper lead between (+) terminal of battery and S terminal on solenoid to test solenoid condition. If starter works, then there's nothing wrong with it; instead; problem lies either in wiring, neutral start switch or ignition switch. If still no operation take out the starter/solenoid assembly for further testing and repair. Make sure your battery is charged and all terminal connections are tight if Starter cranks engine slowly at low speed. Slow starting may result from partial seizure of engine or presence of oil with wrong viscosity in it. Allow the engine to reach its normal operating temperature before testing the starter, then disconnect coil wire from distributor cap and ground it on engine block after which take voltmeter readings as follows: Connect positive lead of volt meter to S terminal on solenoid and negative one to ground; have someone turn ignition switch on while you keep an eye out for any change in voltage readings on voltmeter; do not forget that 9-volts or more reading means faulty Starter provided normal cranking speed persists while less than 9-volts reading suggests slow cranking speed caused by burned solenoid contacts.

After installing the first set of brushes, repeat the same operations for the second set of brushes.

Detach the cable from the negative terminal of the battery and ensure the lockout feature is turned off if applicable.

Check the shift lever (Neutral or Park for automatic transaxle) or depress the clutch pedal (manual transaxle).

To test the armature for ground, use a lamp-type circuit tester by placing one lead on the armature core or shaft and the other on a segment of the commutator; if the lamp lights, the armature is grounded and must be replaced.

Connect the ground wire to the grounded brush and the field lead wire to the insulated brush. Repeat these operations for the second set of brushes.

Finally, install each of the wires to the solenoid terminals using your identification coding.

If the starter motor still does not operate, remove the starter/solenoid assembly for testing and repair.

The location of any shims used.

To test the starter motor's performance with a voltmeter, run the engine until it reaches normal operating temperature, then disconnect the coil wire from the distributor cap and ground it on the engine. Connect a voltmeter positive lead to the positive battery post and the negative lead to the negative post. Crank the engine and take voltmeter readings as soon as a steady figure is indicated, not exceeding 15 seconds of starter motor turning. A reading of 9 volts or more at normal cranking speed is normal. If the cranking speed is slow and the reading is less than 9 volts, it could indicate various issues like burned solenoid contacts, a bad starter motor, discharged battery, or a bad connection.