Starter - Delco-Remy Buick Electra VI

DESCRIPTION

Three types or sizes of 12-volt starting motors are used. All are equipped with an enclosed solenoid, shift lever and overrunning clutch. The starting motor circuits differ depending upon the load and speed requirements.

The 5MT series starting motor differs from the 10MT series in that the 5MT has its field coils permanently mounted in the frame and the 10MT has an optional center bearing.

OPERATION

In the basic starting circuit, the solenoid windings are energized when the switch is closed. This causes the plunger and shift lever to move the drive pinion into the flywheel ring gear. The solenoid main contact closes, causing cranking of the engine.

When the engine starts, the pinion overrunning clutch prevents armature damage caused by excessive speed. When the starting switch is opened, the return spring disengages the pinion from the flywheel.

TROUBLE SHOOTING

Note. See TROUBLE SHOOTING - BASIC PROCEDURES article in the GENERAL TROUBLE SHOOTING section.

SOLENOID WINDINGS TEST

Note. Tests are performed on the solenoid with the motor leads disconnected to prevent overheating. Complete the tests in a minimum of time to prevent further overheating.

Hold-In Winding

1. Connect an ammeter in series with a 12-volt battery and the "S" terminal on the solenoid. (Scheme 1) Connect a voltmeter between the solenoid "S" terminal and ground. Connect a carbon pile rheostat across the battery.
2. Adjust voltage to 10 volts. The ammeter reading should be 14.5-16.5 amps for all starters.

Pull-In Windings

To check both windings, connect test equipment. (Scheme 1) Ground terminal "M" (motor) of the solenoid. Adjust voltage to 10 volts and note ammeter reading. If ammeter reading is 41-47 amps, starter solenoid is good.

Test Results

If current draw readings are above specifications, a short or ground is indicated in the windings of the solenoid. Low current draw readings indicate excessive resistance. If no current is indicated, there is an open circuit. Check connections and replace starter solenoid if necessary.

Solenoid Winding Test Connections Switch must be open when making the connections. Scheme 1

STARTER NO-LOAD TEST

Note. Make all connections and disconnections of equipment with the switch in "OFF" position.

Scheme 2

1. To perform test, connect test equipment to the starter. (Scheme 2) Close switch and compare RPM, amperage, and voltage readings with specifications. See «STARTER NO-LOAD TEST SPECIFICATIONS»(/buick/electra/vi-1985-1990/remont/starter/#starter-delco-remy) table. (Scheme 2): Starter No-Load Connections The switch must be open when making the connections. CAUTION: DO NOT apply voltage greater than specified. Excessive voltage may cause the armature to throw its windings because of the excessive speed.
2. If the current draw and RPM meet specifications, the condition of starter motor is normal. If the test indicates low free speed and high current draw, the problem could be too much friction resulting from tight, dirty or worn bearings, shorted armature, or grounded armature or fields.
3. Failure to operate with high current draw indicates a direct ground in the terminal fields or frozen bearings. Failure to operate with no current draw indicates an open field circuit, open armature coils, or broken brush springs.
4. Low no load RPM and low current draw indicates high internal resistance due to poor connections, defective leads, or a dirty commutator. High free speed and high current draw indicates shorted fields.

DISASSEMBLY

1. Remove the field coil connector and solenoid housing mounting screws from the solenoid. After rotating the solenoid 90 degrees, remove solenoid and plunger return spring.
2. Remove the 2 through bolts. Remove commutator end frame. Remove the plunger/shift lever assembly and armature assembly with the overrunning clutch from the drive end housing. Remove the thrust washer or collar from the armature shaft. Slide a 5/8" deep socket over the shaft against the retainer as a driving tool.
3. Tap the tool to move the retainer off the snap ring. Remove the snap ring from the groove in the shaft. If the snap ring is distorted, it must be replaced upon assembly. Remove the retainer and clutch assembly from the armature shaft.

CLEANING & INSPECTION

1. When cleaning starter parts DO NOT use grease dissolving solvents, solvent will dissolve the grease packed in the clutch and would damage armature and field coil insulation.
2. Inspect armature commutator, shaft and bushings and springs for discoloration, damage or wear.
3. Check fit of armature shaft in bushing in drive housing. Shaft should fit snugly in the bushing. If the bushing is worn, replace bushing.
4. Inspect armature commutator. If commutator is rough, it should be turned down. DO NOT machine out-of-round commutators. Inspect the points where the armature conductors join the commutator bars to make sure they have a good connection. A burned commutator bar is usually evidence of a poor connection.

BENCH TESTS

Note. The following tests are made following removal or partial disassembly of the starter.

PRELIMINARY TESTS

With the starter motor removed from the engine, the pinion should be checked for freedom of movement by turning it on the screw shaft. The armature should be checked for freedom of rotation by prying the pinion with a screwdriver. If the armature does not turn freely, the motor should be disassembled immediately. However, if the armature does rotate freely, the motor should be given a no-load test before disassembly.

ARMATURE

1. Test the armature for shorted coils with a growler. Check for grounded coils with a test light. Place one test lead on the armature shaft and the other test lead on the commutator. The lamp should not light. If the lamp lights, the armature is grounded and should be replaced.
2. Inspect the commutator. If the commutator is rough, worn, or has protruding insulation, turn the commutator in a lathe. DO NOT turn to less than 1.65" (41.9 mm) diameter. Sand the commutator lightly with 240 grit emery paper and carefully clean out the slots.

SERIES COIL OPEN TEST

Using a test lamp, place one lead on the series coil terminal and other lead on the insulated brush. If the lamp fails to light, the series coil is open and requires repair or replacement. Repeat the test for each insulated brush to check it and its coil continuity.

SHUNT COIL OPEN TEST

Using test lamp, place one lead on shunt coil terminal and other lead to one ground brush holder. Repeat test for other ground terminal. If lamp fails to light on either test, field coil is open and must be repaired or replaced.

SERIES & SHUNT COIL GROUND TEST

Separate series and shunt coil strap terminals. DO NOT let terminals contact case or ground during test. Using test lamp, place one lead on the grounded brush holder and the other lead to either insulated brush holder. If lamp lights, series coil is grounded and must be repaired or replaced.

BRUSHES, SPRINGS & HOLDERS

Replace the brushes if they are worn to 1/2 of the original length or if they are oil-soaked, or pitted. Check the brush spring tension and replace the springs if weak or distorted. Deformed or bent brush holders can be replaced by service units.

OVERRUNNING CLUTCH CHECK

The clutch pinion should turn freely in one direction only. Check the pinion teeth for chips, cracks, or excessive wear. Chipped teeth may indicate a defective ring gear.

PINION CLEARANCE CHECK

1. Disconnect the motor field coil at the solenoid "M" terminal and insulate the field connector. Connect a 12-volt battery positive lead to the solenoid "S" terminal and the other to ground. Touch a jumper lead from the solenoid "M" terminal to the starter frame, shifting the pinion into the cranking position.
2. Push the pinion away from the stop retainer as far as possible. Using a feeler gauge, check for.010-.140" (.25-3.6 mm) clearance between the pinion and retainer. (Scheme 3)

Note. The pinion clearance is not adjustable. If clearance is not within specifications, the motor must be disassembled and checked for worn or defective parts.

Checking Pinion End Play. Scheme 3

Scheme 4

All Models

1. Lubricate the drive end of the armature shaft with silicone lubricant. Install the center bearing (27MT only) with the bearing facing the armature winding. Install the fiber washer on the armature shaft.
2. Slide the clutch assembly onto the armature shaft with the pinion away from the armature. Slide the retainer onto the shaft with the cupped side facing the shaft end. Install the snap ring into the groove on the shaft. Install the thrust washer.
3. Position the retainer and the thrust washer with the snap ring located between them. Using 2 pliers, grip the retainer and thrust washer; then squeeze it until the snap ring is forced into the retainer and is held securely in the armature shaft groove.
4. Lubricate the drive gear housing bushing. Engage the shift lever yoke with the clutch and slide the complete assembly into the drive gear housing.
5. Install the center bearing screws and the shift lever pivot bolt. Install drive housing, tighten though bolts and install the solenoid assembly on the drive gear housing. Test starter and install.
6. Apply sealer to the solenoid flange where the field frame contacts it. Position the field frame against the drive gear housing on the alignment pin, being careful not to damage the brushes. Lubricate the commutator end frame bushing with lubricant.
7. Install the washer on the armature shaft and slide the end frame onto the shaft. Install the through bolts and tighten. Connect the field coil connector to the solenoid "M" terminal. Ensure the through bolts pass through the bolt holes in the insulator. Check the pinion clearance.

STARTER SPECIFICATIONS

STARTER NO-LOAD TEST SPECIFICATIONS

Cranking Circuit (Typical). Scheme 5

See also:
• TROUBLE SHOOTING - BASIC PROCEDURES
• STARTER NO-LOAD TEST SPECIFICATIONS