DESCRIPTION
Starter is a brush type, series wound electric motor with an overrunning clutch. Field frame is enclosed by commutator end frame and drive bushing and carries pole shoes and field coils. A spline armature shaft drive end carries drive assembly. Armature shaft is supported at both ends by sintered bronze bushings.
STARTER LOAD (LOCK) TEST
With starter on test bench, lock starter drive pinion. Voltmeter and ammeter readings should be within specification.
| Application | Volts | Amps | |
|---|---|---|---|
| 240 Series (1) | 7.0 | 480-560 | |
| 740, 760 & 780 Series | |||
| Bosch GF (1.1 kW) (2) | 7.4 | 480-560 | |
| Bosch DW (1.4 kW) | 4.5 | 625-800 | |
| Bosch JF (2.0 kW) | 4.5 | 700-880 | |
| (1) At 6.0 volts, ammeter reading should be 330-420 amps. (2) At 6.5 volts, ammeter reading should be 410-490 amps. | |||
| (1) | At 6.0 volts, ammeter reading should be 330-420 amps. |
| (2) | At 6.5 volts, ammeter reading should be 410-490 amps. |
STARTER LOAD (LOCK) TEST SPECIFICATIONS
STARTER NO LOAD TEST
With starter on test bench, operate starter and check ammeter, voltage, and RPM. Readings should be within specification.
| Application | Volts | Amps. | RPM | |
|---|---|---|---|---|
| 240 Series | 11.5 | 70 | 7500 | |
| 740, 760 & 780 Series | ||||
| Bosch GF (1.1 kW) | 11.5 | 70 | 7500 | |
| Bosch DW (1.4 kW) | 11.5 | 75 | 900 | |
| Bosch JF (2.0 kW) | 11.5 | 65-95 | 6500 | |
STARTER NO LOAD TEST SPECIFICATIONS
Exploded View of Typical Bosch Starter. Scheme 1
STARTER DOES NOT CRANK ENGINE
- Ensure battery is fully charged. Make sure electrical and ground connections are clean and tight. With ignition switch in crank position, measure voltage at spade terminal of starter solenoid. If reading is at least 8 volts, go to step 3).
- If not, measure voltage at ignition switch. If reading is at least 8 volts, check wiring between ignition switch and starter solenoid. If not, replace ignition switch.
- Measure voltage at field (starter) terminal of starter solenoid. If reading is at least 8 volts, repair or replace starter. If not, replace starter solenoid.
Note. On vehicles with automatic transmissions, also check park/neutral switch.
STARTER TURNS TOO SLOWLY
Ensure engine crankcase is filled with recommended viscosity oil. Check charging system to ensure battery is fully charged. Make sure electrical and ground connections are clean and tight. If starter still turns slowly, repair or replace starter.