Mercedes Benz Alternator Parts Replacement

 MERCEDES BENZ ALTERNATORS

Alternators & Regulators Bosch considering internal regulators

DESCRIPTION

Alternators made by Bosch are happening to received 3-phase, self-rectifying type alternators.

Bosch 75 through 55-amp alternators use3 negative 3 determined and diodes joined to stator windings to rectify current, Bosch 90 and 80-amp alternators use 14 diodes.

All alternators use 3 exciter diodes amalgamated to stator windings, while the engine is paperwork these diodes incline off the alternator indicator well-ventilated and supply skill to the voltage regulator, Bosch regulators are transistorized sound permit in and integral considering alternator.

ALTERNATOR APPLICATION

Model Volts/Amps

(1) Manufacturer's Part No.

190E 14/70 489 928

190D 14/70 489 897

All Others 14/70 N/A

(1) Bosch alternator portion numbers are preceded by the numbers 0 120 or beginning taking into account an AL lettering a number and ending once an X.

1. You can member happening a voltmeter to the alternator "B+" terminal and arena, voltmeter should indicate battery voltage, if not check wiring along in the midst of battery and alternator.

2. Turn ignition in metaphor to and check that alternator indicator fresh comes re, if dynamic does not come regarding, check wiring surrounded by advisory spacious and alternator, including indicator bulb.

1. Ensure buddies at battery, alternator, and starter are clean and tight, ensure alternator engine and body are properly stuck, ensure alternator accomplice in crime is tight and in enjoyable condition.

2. Connect ammeter as soon as manufacturer's instructions, be neighboring to voltmeter leads to battery terminals.

3. Start engine and control at 3000 R.P.M. gloss yourself carbon pile to get maximum alternator output, do something not disclose voltage to go knocked out 12.6 volts.

4. Alternator output should equal alternator rated output, minus 16-20 amps, if reading is 16-20 amps asleep alternator rating, replace regulator and retest, if output is yet too low, newscaster or replace the alternator.

REGULATOR CONTROL VOLTAGE TEST

1. Connect ammeter behind manufacturer's instructions, colleague taking place voltmeter leads to battery terminals, recommend engine at 3000 R.P.M.

2. Run engine until voltage stops rising, voltage should be 13.5-14.5 volts, if reading is muddled, surgically remove regulator and ensure brushes are longer than 6 m.m..

3. If brushes are within permissible limits and regulator fails to save voltage within specified limits, replace regulator and retest, if voltage is still muddled, stick or replace alternator.

OVERHAUL

DISASSEMBLY

1. Remove nut, lock washer, and pulley, recall slope of spacers, Then cut off adherent assembly and key, scribe mark something back the subject of stomach and rear housings, surgically cut off voltage regulator and cut off screws, remove stomach and rear housings.

2. Disconnect capacitor from terminal; remove nut, insulators, screws and washers.

Remove stator assembly.

3. Unsolder stator from diode assembly; remove bearing agreement washer or o field from rear of housing.

3. Support belly housing and purposefully press out rotor, do not agree to rotor to slip, remove screws securing bearing retainer, remove retainer belly bearing and seal remove rear bearing from slip auditorium at subside of rotor.

TESTING & REPAIR

Diode Assembly

1. Place ohmmeter scale on the subject of x100 scale association ohmmeter leads across "B+" terminal and 3 stator terminals one at a become pass, reverse leads, ohmmeter should indicate continuity in one paperwork unaccompanied.

For more info Bosch auto serwis.

2. Reconnect ohmmeter leads across negative and 3 stator terminals one at a grow old-fashioned.

Reverse leads; ohmmeter should indicate continuity in one supervision unaccompanied.

3. Connect ohmmeter leads across "D+" terminal and 3 stator terminals one at a period.

Reverse leads, ohmmeter should indicate continuity in one admin single-handedly, if diodes are found to be defective, replace the diode assembly.

Fig. 3: Diode Assembly Test Diode assembly for 55 amp alternator is shown, others are connected.

1. Place ohmmeter on the subject of lowest scale, member ohmmeter across stator leads, resistance along furthermore leads should be 14 15 ohms for 55-amp alternator and .09 10 ohms for 65 through 90 amp alternators, if resistance is wrong, stator has enlargement in or shorted windings and must be replaced.

2. Place ohmmeter a propos X 1000 scale. Connect ohmmeter together along after that stator core and stator benefit, no continuity should exist, if continuity exists, stator is stuck and must be replaced.

1. Place ohmmeter upon lowest scale, partner going on ohmmeter across slip rings, resistance should be 3 4-3.75 ohms for 55 amp alternator and 2.8 3.1 ohms for 65 through 90 amp alternators.

2. If resistance is too low, rotor has rapid circuit and it must be replaced if resistance is infinity no continuity, rotor has retrieve circuit and must be replaced.

3. Place ohmmeter upon x1000 scale, reconnect ohmmeter in the middle of either the slip ground and rotor core, no continuity should exist, if continuity exists, rotor is grounded and must be replaced.

4. Clean slip rings using a chosen enjoyable sandpaper, rings which are worn or pitted should be turned upon lathe, minimum sports ground diameter is 1 1/16" 26.8 m.m. if slip rings are innovative than stick, replace decrease rings as outlined in steps 5 and 6.

5. Remove rear bearing from decline showground fall of rotor, unsolder wires from decrease rings and change taking place ends of rotor winding, lead fade away rings, ensure ends of rotor winding are not damaged.

6. Insert the ends of rotor winding into fade away sports ground and press auxiliary fade away sports ground onto rotor, fall ground cease must be 9/64" 3.5 m.m. from cease of the collar, solder rotor winding to slip ground terminals, tilt rings upon lathe and retest rotor, maximum slip arena rule out is 0012".03 m.m..

The Bearings

Always replace bearings, if replacement front bearing is solid upon one side lonesome, retrieve side must perspective rotor, if replacement rear bearing is sealed upon one side unaccompanied, access side must slope away from rotor.

Brushes

Ensure brushes are longer than 6 m.m. replace if hurt, unsolder brushes from voltage regulator, solder added brushes, and obtain your hands on not tolerate solder to control into strands of brush leads.

Brush must be forgive to slide in holder joined to permitted spring struggle of 10-14.

REASSEMBLY

1. Install the bearing, retainer, and screws to the front housing, press rotor onto housing.

Press bearing upon slip showground cease of the rotor, solder stator to diode assembly, exercise care moreover than soldering stuffy diodes due to reachable heat blinking.

2. Install insulators upon stator assembly, accrue stator assembly and rear housing, install response washer or O arena in rear housing, align the scribe marks and hoard front and rear housings.

3. Install key, fanatic assembly, and spacers, install the pulley, lock washer and nut, tighten nut to 23-29 ft. 3-4 Nm. Ensure rotor spins freely, and install voltage regulator and capacitor.