JF Series Starting Motor Caterpillar

Visually check the field winding assembly. Check for wear and check for damage. Check all connections for solder joints that are clean and tight.

Field Winding Ground Test

Show/hide table



Illustration 1	g00719285
Field winding ground test (1) Field winding leads (2) Motor terminal lead "Mtr"

1. Put the Digital Multimeter on the "20M" resistance scale. Touch the meter leads between each field winding lead (1) and the starting motor housing.

2. Touch the meter leads between the motor terminal lead "Mtr" (2) and the starting motor housing.

3. Each reading should be greater than 100,000 ohms.

4. If any meter reading is less than 100,000 ohms, the field winding is grounded and the field winding must be rebuilt or replaced.

Field Winding Continuity Test

Illustration 2	g00719330
(1) Field winding leads (2) Motor terminal lead "Mtr"

1. Put the Digital Multimeter on the "200 ohm" resistance scale. Touch the meter leads between the field winding leads (1) .

2. Touch the meter leads between each of the field winding leads (1) and the motor terminal lead "Mtr" (2) .

3. Each reading should be 0.00 to 0.80 ohms.

4. If any of the meter readings is higher than Step 3, there is an open in the field winding and the field winding must be rebuilt or replaced.