Alternator - Models W/integral Regulator Ford Bronco II I

DESCRIPTION

Rated outputs for integral regulator alternator range from 40 to 65 amps. Alternator field current is supplied from the regulator to the rotating field through brushes contacting slip rings. Alternating current is produced and then rectified to direct current by the use of diodes. The regulator automatically adjusts field current to maintain alternator output.

Charging systems are equipped with a fusible link, used to prevent system damage. Warning light is used to indicate charging system failure.

VOLTAGE REGULATOR

Solid state regulator is used. Regulator is factory calibrated and cannot be adjusted.

TROUBLE SHOOTING

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

Battery

Do not reverse battery connections. Negative terminal must be connected to ground. When charging battery, remove ground cable before connecting charger. If booster battery is used to start engine, negative cable of booster must be connected to vehicle frame. Disconnect negative booster cable first.

Do not ground circuits or attempt to polarize alternator.

CHARGING SYSTEM TESTING

Note. Ensure that battery is fully charged and battery connections are clean and secure. On non-maintenance free batteries specific gravity must be at least 1.200 prior to testing. Check that alternator drive belt is adjusted to proper tension.

1. Ensure that all accessories are turned off. Use voltmeter to measure battery voltage. Attach tachometer and start engine. Operate at 1500 RPM with no electrical load. Voltmeter reading should increase but no more than 2 volts above battery voltage. Reading should be taken when voltmeter needle stabilizes.
2. With engine operating, turn heater or A/C blower motor to "HIGH" position. Turn on headlights to high beam. Increase engine speed to 2000 RPM. Voltmeter should indicate a minimum of .5 volt above battery voltage.

Scheme 10

1. If voltmeter reading indicates more than 2 volts above battery voltage, stop engine. Connect voltmeter negative lead to alternator housing. Connect voltmeter positive lead to alternator output post of stator solenoid.
2. Turn ignition switch to "ON" position. Note voltage reading. Move voltmeter to "A" terminal screw on rear of voltage regulator. (Scheme 10) Note reading at this point.
3. Difference between voltage readings should not exceed.5 volt. If difference exceeds.5 volt, check "A" terminal wiring circuit for high resistance. Repair as necessary.
4. If voltage reading still exceeds.5 volt, check for loose regulator-to-alternator mounting screws. Recheck voltage. If excessive voltage still exists, perform the following procedure.
5. Turn ignition switch to "OFF" position. Connect positive voltmeter lead to regulator "A" terminal screw. Install remaining lead on alternator "F" terminal screw. Voltage should read the same at both test locations.
6. Different voltage readings indicates defective regulator, grounded brush lead or grounded rotor coil. If readings were the same, resistance is normal in the ground circuit. Replace components as necessary.

Scheme 11

1. On voltage readings of less than.5 volt, disconnect wiring plug from regulator. Connect ohmmeter between "A" and "F" regulator terminal screws. (Scheme 10) Reading should exceed 2.4 ohms. Replace alternator if reading is less than 2.4 ohms.
2. If reading exceeds 2.4 ohms, connect wiring plug at regulator. Connect voltmeter negative lead to alternator case. Connect positive lead to regulator "A" terminal screw. Reading should indicate battery voltage. Check "A" terminal wiring circuit if no voltage is present.
3. If reading shows battery voltage, connect voltmeter negative lead to alternator housing. Ensure that ignition switch is in "OFF" position. Connect positive lead to regulator "F" terminal screw.
4. Battery voltage should exist. If battery voltage does not exist, replace alternator due to open circuit.
5. If voltage exists, connect voltmeter negative lead to alternator housing. Turn ignition switch to "ON" position. Connect positive lead to regulator "F" terminal screw.
6. Reading should read 1.5 volts or less. If reading exceeds 1.5 volts, perform test procedure on "I" circuit. See "S" & "I" CIRCUIT under «REGULATOR CIRCUIT TESTS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator).
7. On readings of 1.5 volts or less, disconnect regulator wiring plug. Connect 12 gauge-jumper wire between alternator "BAT" terminal and corresponding terminal on wiring plug. (Scheme 11)
8. Connect voltmeter positive lead to jumper wire. Connect remaining lead to ground. Start engine. Turn heater or A/C blower motor to "HIGH" position.
9. Turn on headlights to high beam. Increase engine speed to 2000 RPM. Repair alternator-to-starter wiring if reading exceeds.5 volt above battery voltage.
10. Connect jumper wire from alternator housing to regulator "F" terminal if voltage is less than.5 volt. Connect voltmeter positive lead to jumper wire. Connect remaining lead to ground.
11. Start engine. Turn heater or A/C blower motor to "HIGH" position. Turn on headlights to high beam. Increase engine speed to 2000 RPM. Replace regulator if voltage exceeds.5 volt. Replace alternator if voltage does not exceed.5 volt.

Scheme 12

1. Remove wiring plug from regulator. Install jumper wire from regulator "A" terminal to wiring plug "A" terminal. Install jumper wire from regulator "F" terminal to rear of alternator housing.
2. Connect voltmeter negative lead to battery negative terminal. Start engine and connect voltmeter positive lead to regulator "S" terminal and then to the "I" terminal. Note reading at each location. (Scheme 12)
3. Voltage reading of terminal "S" should be approximately 1/2 of the "I" terminal voltage. Replace regulator if readings are correct. Repair wiring if voltage is not present.

BENCH TESTING

STATOR GROUNDED TEST

1. Perform test before alternator disassembly. Adjust ohmmeter to x1 scale. Place ohmmeter lead on alternator "BAT" blade terminal. Place remaining lead on the "STA" terminal and note reading. (Scheme 13) Reverse ohmmeter leads and note reading.
2. Reading should not show needle movement in one direction. This indicates rectifier diodes are being checked in reverse current direction. Low reading of approximately 6.5 ohms with leads reversed indicates that positive diodes are being checked in forward current direction.
3. Readings in both directions indicates defective positive diode or shorted radio suppression capacitor. Radio suppression capacitor is built into the rectifier assembly.
4. Place ohmmeter lead on "STA" blade terminal and remaining lead on alternator housing. Reading in both directions indicates a grounded stator winding, defective negative diode, a grounded stator lead wire or shorted radio suppression capacitor.
5. Check for bad connection in rectifier if no reading is obtained in either direction or excessive resistance is obtained.

Scheme 13

Scheme 14

1. Perform test before alternator disassembly. Adjust ohmmeter to x1 scale. Place ohmmeter leads on regulator "A" blade terminal and regulator "F" screw head. (Scheme 14) Rotate alternator pulley and note reading. Reverse ohmmeter leads and repeat test.
2. Reading should be between 2.2 and 100 ohms in one direction. Fluctuation may occur while pulley is turning. Reading should fluctuate between 2.2 and 9 ohms with leads reversed.
3. Reading with approximately 9 ohms in one direction and no reading in the other indicates open brush lead, defective brushes or loose regulator-to-brush holder attaching screws.
4. Reading of less than 2.2 ohms in both directions indicates a shorted rotor or defective regulator. Reading exceeding 9 ohms in both directions indicates a defective regulator or loose "F" terminal screw.
5. Place one lead on alternator rear housing with remaining lead touching regulator "F" terminal. Note reading. Reverse leads and repeat test. Reading should be infinite in one direction and approximately 9 ohms with leads reversed.
6. Reading less than infinite in both directions indicates a grounded brush lead or defective regulator. Reading exceeding 9 ohms in both directions indicates defective regulator or "A" terminal connection.

Scheme 15

RECTIFIER TEST

1. Remove rectifier from alternator. Adjust ohmmeter to x1 scale. Place one lead on one of rectifier "BAT" blade terminals. Place other lead on each of the 3 stator terminals. (Scheme 16) Reverse leads and repeat test. Note readings in both directions.
2. Reading of approximately 7 ohms in one direction and no reading with leads reversed should be obtained.
3. Place one lead on rectifier base plate and remaining lead on each of the 3 stator terminals. This is done to test negative diodes. Reverse leads and repeat test.
4. Reading of approximately 7 ohms in one direction and no reading with leads reversed should be obtained. If readings are not correct, replace rectifier.

Scheme 16

Note. This is a circuit test only and does not measure capacity value.

RADIO SUPPRESSION CAPACITOR OPEN OR SHORT TEST

1. Adjust ohmmeter to x1000 scale. Place ohmmeter lead on one of rectifier "BAT" blade terminals and remaining lead on rectifier base plate. Reverse leads and repeat test. Note reading in both positions.
2. Infinite reading should be obtained in one direction. This indicates reverse current direction through the diodes. Reading of approximately 1000 ohms should be obtained in the other direction. This indicates the forward current direction.
3. Replace rectifier if same reading is obtained in both directions. Capacitor can be checked for shorts by placing leads to rectifier "BAT" terminal and base plate in the forward (1000 ohms) current direction.
4. Observe ohmmeter indicator needle while reversing leads and again contacting them to rectifier "BAT" terminal and base plate. Indicator should jump slightly.
5. This indicates that ohmmeter batteries are charging the capacitor. Indicator should then return to infinite reading. If indicator does not jump, capacitor is open. Replace rectifier assembly.

STATOR COIL GROUND TEST

1. Stator must be removed from the rectifier. Adjust ohmmeter to x1000 scale. Place ohmmeter lead on the stator lead terminals and remaining lead on the stator laminated core. (Scheme 17)
2. Ensure lead makes good connection with stator core. Ohmmeter should show no reading. Stator winding is grounded to the core if reading is obtained. Replace stator if grounded.

Scheme 17

STATOR OPEN TEST

1. Separate stator from rectifier. Adjust ohmmeter to x1 scale. Place one lead to a stator terminal. Place remaining lead on another stator lead. Note meter reading. Ohmmeter reading should be obtained.
2. Stator winding is open if reading is not obtained. Replace stator coil if open is found. Repeat test procedure on remaining stator leads.

ROTOR OPEN OR SHORT TEST

1. Adjust ohmmeter to x1 scale. Place each ohmmeter lead on rotor slip rings. (Scheme 18) Note ohmmeter reading. Reading should be 2.0-3.9 ohms.
2. Reading exceeding specification indicates a damaged slip ring, welded connection or a broken wire. Low reading indicates a shorted wire or slip ring.
3. Place one ohmmeter lead to a slip ring and remaining lead on rotor shaft. No reading should be obtained. Rotor coil is grounded to shaft if reading is obtained. Repair or replace rotor if defective.

Scheme 18

Scheme 19

1. Remove regulator mounting screws from alternator rear housing. Remove regulator and brush holder. Remove "A" terminal insulator. Remove regulator-to-brush holder retaining screws.
2. Separate regulator, attaching nuts, brushes and brush springs from brush holder. Mark a scribe line across end housings and stator core for reassembly reference. Remove through bolts.
3. Separate front housing with rotor from stator and rear housing. Remove stator lead terminals from rectifier. On soldered connections, unsolder connections using a 100-watt soldering iron. Use care not to apply direct heat to rectifier.
4. Use needle-nose pliers to separate stator leads from rectifier. Some models use a connector block. Leads are not soldered on these models.
5. Fabricate small tool and carefully pry connector block upward. (Scheme 19) Use care not to bend connections. Remove stator from rear housing.
6. Remove rectifier mounting screws. Remove rectifier from housing. Using an arbor press, remove bearing from rear housing. Support housing close to bearing boss to prevent damage.
7. Place rotor in soft-jawed vise. Use care not to damage rotor. Remove pulley retaining nut. Remove flat washer, pulley, fan and fan spacer from rotor shaft. Remove rotor from housing and remove housing from vise.
8. Remove rotor stop from rotor shaft. Do not remove stop ring unless replacement is required. Remove front bearing retainer screws. Remove retainer. Using an arbor press, remove bearing from front housing. Support housing close to bearing boss to prevent damage.

CLEANING & INSPECTION

1. Rotor, stator and bearing must not be cleaned with solvent. Clean these components with a clean cloth. Clean remaining components with clean solvent. Inspect bearings for signs of lubricant loss and signs of roughness.
2. Inspect rotor shaft bearing area for signs of bearing movement. Inspect all soldered connections on rotor and stator for looseness. Inspect rotor and stator for signs of burned insulation.
3. Inspect rotor slip rings for nicks or roughness. Rotor slip rings can be turned down to remove nicks or roughness. Rotor slip rings must not be turned smaller than specification. See «ALTERNATOR SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table.
4. Check pulley and fan for excessive looseness or cracks on rotor shaft. Check front and rear housings for cracks in webbed areas at mounting ear.
5. Check brush length. Replace brushes if worn less than .250" (6.35 mm). Replace all damaged components.

Scheme 20

1. Install bearing into front housing. Press on outer race only. Position bearing retainer on front housing. Install attaching screws. Tighten screws to specification. See «TORQUE SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table.
2. Install new stop ring (if removed). Stop ring must be positioned in the groove farthest from rotor pole piece. Use care not to deform rotor stop ring during installation. NOTE: Do not open ring with snap ring pliers, as permanent damage will result.
3. Position rotor stop on rotor shaft. Recessed side must be against stop ring. Place rotor in soft-jawed vise. Install front housing, fan, spacer, drive pulley, washer and nut on rotor shaft.
4. Tighten nut to specification. See «TORQUE SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table. Remove rotor and housing from vise. Check rotor for rotation freedom.
5. Place rear housing in arbor press. Support rear housing close to bearing boss. Install bearing until it is even with outside surface of housing.
6. Clean rectifier base plate with a clean cloth. Apply a 3/32" (2.0 mm) wide by 3/4" (20 mm) long strip of Heat Sink Compound (ESF-M99G138-A) lengthwise across rectifier base plate. CAUTION: Rectifier is cooled by conducting heat directly into rear housing. Failure to apply heat sink compound may cause rectifier overheating.
7. Ensure rear housing rectifier mounting surface is clean. Install rectifier into recessed mounting area. Install rectifier retaining screws. Tighten screws to specification. See «TORQUE SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table.
8. Install stator in rear housing and align scribe marks. Install the 3 stator terminals onto rectifier blade terminals. Solder securely using resin core solder if connections were originally soldered. Use care not to apply direct heat to rectifier.
9. Clean rear bearing surface of rotor shaft with a clean cloth. Install rear housing and stator over rotor. Align scribe marks. Ensure that machined area of stator core seats in both end housings.
10. Install through bolts. Tighten to specification. See «TORQUE SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table. Install springs and brushes in brush holder.
11. Retain brushes in place by inserting a 1 3/8" (35 mm) piece of stiff insulated wire into brush holder pin hole. (Scheme 20) Install nuts and washers in retaining slots of brush holder.
12. Position brush holder backward so that nuts and washers fall toward nut side of slots. This allows clearance for brush terminal installation. Install brush terminals behind washers into slots. Clean brush holder mounting area on regulator assembly.
13. Position brush holder on regulator. Install regulator-to-brush holder attaching screws. Tighten screws to specification. See «TORQUE SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table.
14. Loop brush leads toward brush end of holder. Install adhesive backed insulator on "A" terminal screw head. Clean regulator mounting surface of alternator housing using a clean cloth.
15. Install regulator and brush holder on rear housing. Install regulator attaching screws. Tighten screws to specification. See «TORQUE SPECIFICATIONS»(/ford/bronco-ii/i-1984-1990/remont/charging-system/#alternator-models-wintegral-regulator) table. Remove brush retaining wire. CAUTION: Ensure brush retaining wire is removed. Regulator will be damaged if wire is not removed.
16. Place a small amount of waterproof sealer over brush pin hole. Do not use silicone sealer. Rotate pulley to check for freedom of movement.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

SPECIFICATIONS

ALTERNATOR OUTPUT

ALTERNATOR SPECIFICATIONS

See also:
• TROUBLE SHOOTING - BASIC PROCEDURES
• REGULATOR CIRCUIT TESTS