Starter Inspection. Buick Roadmaster 1996

For 1990-2009 cars

Notice: Do not use grease dissolving solvents for cleaning the overrunning clutch or armature. Solvents dissolve the grease packed in the clutch and damage the armature and the field coil insulation.

1. Clean all starter motor parts. Wipe the parts clean with a clean shop cloth.
2. Test starter drive action. The pinion should run freely in overrunning direction. Check the pinion teeth for chipping, cracking or excessive wear. Replace the starter drive if necessary. Badly chipped pinion teeth may indicate chipped teeth on the flywheel. Replace as necessary.
3. Check the starter drive for slipping by leaving the starter drive attached to the armature. Wrap the armature with a shop towel and clamp it in a vice. Using a 12-point deep socket and a torque wrench, put the socket on the pinion and torque counterclockwise. Drive should not slip with up to 68 N·m (50 ft lb) of applied torque. If it does, replace the starter drive.
4. The starter drive requires no lubrication; however, the starter drive should be wiped clean.
5. Inspect the armature commutator. If the commutator is dirty, clean with a 400 grit polishing cloth. If the commutator is rough, replace the armature. Do not undercut or turn the commutator. Inspect the points where the brushes join the commutator bars to make sure that they have a good connection. A burned commutator bar is usually evidence of a poor connection.
6. Inspect brushes and brush holders. When the brushes appear excessively worn when compared to new brushes they should be replaced. Make sure the brush holders are clean and the brushes are not binding in the brush holders. Full brush surface should ride on commutator to give proper performance.

• | Check to ensure that brush springs are giving firm contact between brushes and commutator. When brush springs are distorted or discolored, they should be replaced.

• | All brush and brush holder parts are part of the frame kit.

7. Check the armature for short circuits by placing on growler and holding the hacksaw blade over the armature core while the armature is rotated. If the saw blade vibrates, the armature is shorted. Replace the armature.
8. Check the field windings by using a self-powered test lamp. Place one lead on the field lead terminal and the other lead on one insulated brush. If the lamp fails to light, the series coil is open and will require repair or replacement. Perform this test for each insulated brush to check brush and lead continuity.
9. Using self-powered test lamp, place one lead on grounded brush holder and the other lead on either insulated brush. If the lamp lights, grounded series coil is indicated and frame kit must be replaced.
10. Check the armature for grounds using a self-powered test lamp. Place one lead on the commutator and the other lead on the armature core or the shaft. If the lamp lights, the armature is grounded and must be replaced.
11. Check the current draw of solenoid windings as follows:

11.1. | If the solenoid switch is not removed from the starter motor, the field lead must be removed from the "M" terminal on the solenoid switch before making these tests. Complete the tests in a minimum of time to prevent overheating of the solenoid switch.

11.2. | To check hold-in winding, connect the ammeter in series with a 12-volt battery and "S" terminal on the solenoid switch. Connect the voltmeter to the "S" terminal and the ground. Connect the carbon pile across the battery. Adjust the voltage to 10 volts and note the ammeter reading. Reading should be 10 to 20 amperes.

11.3. | To check both windings, connect as for previous test. Ground solenoid "M" terminal. Adjust voltage to 10 volts and note the ammeter reading. The reading should be 56 to 80 amperes.

Important:

• | Current will decrease as windings heat up.

• | Current draw readings that are over specifications indicate shorted turns or a ground in the windings of the solenoid switch (56) and the solenoid switch should be replaced. No or low current draw readings that are under specifications indicate excessive resistance. A zero reading indicates an open circuit. Check the connections, then replace the solenoid switch if necessary.

• | The solenoid switch is serviced as an assembly.