C0.5 and C0.7 Industrial Engines Caterpillar

Starting Motor

Illustration 1	g00379835
Starting motor and starting motor solenoid

No load conditions at 25°C (77°F)

Rpm with no load ... 4000 to 6000 rpm

Maximum current ... 540 A

Current draw with no load ... 130 A

Voltage ... 11.5 V

Rated voltage ... 12 V

Power rating

C0.5 and C0.7 Standard ... 0.8 kW

Option ... 1.2 kW

Minimum average cranking rpm ... 130

Starting motor solenoid

Pull-in current ... 54.5 A

Hold-in current ... 10.5 A

(1) Tighten the battery terminal nut to the following torque. ... 15 N·m (11 lb ft)

(2) Tighten the two mounting bolts to the following torque. ... 50 N·m (37 lb ft)

(3) Tighten the nut for the switch terminal to the following torque. ... 1.0 to 1.3 N·m (9 to 12 lb in)

Maximum resistance of the starter cable at 20°C (68°F) and at 12 volts ... 0.04 ohms

Start Relays

Illustration 2	g00381753
Schematic of the relays

(4) When the ignition switch is in the OFF position or the RUN position, the relay switch is closed across the contact "30" and the contact "87a".

(5) When the ignition switch is in the START position, the relay switch is closed across the contact "30" and the contact "87". Then, the starting motor is engaged.

Maximum voltage drop in closed position ... 0.150 to 0.250 volts

(6) Connector pins on the start relay

Resistance between contact "85" and contact "86" ... 7.2 ± 0.7 ohms