Brushes; Field Coil; Stator Coil; Alternator - Toro Groundsmaster 580-D Service Manual

Alternator

The alternator used on the Groundsmaster 580--D is
belt driven and attaches to the engine. If testing deter-
mines that alternator is not functioning properly, bench
inspection should be performed.
Note: For information on disassembly and assembly
of the alternator used on models 30581, 30582 and
30583, see the Mitsubishi S4S--DT Service Manual that
follows Chapter 3A -- Engine (Model 30581).

Brushes

Replace the alternator brushes if they are worn to the
service limit (Fig. 18).
Brush Length
MODEL
30581
(50 Amp Alternator)
30581 (w/AC Kit)
(75 Amp Alternator)
30582 & 30583 (100
Amp Alternator)

Field Coil

Measure the resistance between the slip rings (Fig. 19).
If the resistance is outside of the assembly standard, re-
place the rotor.
MODEL
30581
30581
(with AC Kit)
30582 & 30583

Stator Coil

Check for continuity between the lead wires (Fig. 20). If
no continuity exists (infinite resistance), the coil has an
open circuit and needs to be replaced.
Check for continuity between the lead wires and the sta-
tor core laminations. If continuity exists (no resistance),
the stator coil is grounded and needs to be replaced.
Rectifier
Test the resistance between each diode lead wire and
heat sink (Fig. 21). To test, connect the positive (+) multi-
meter test lead to the diode and the negative (--) multi-
meter test lead to the heat sink, record resistance and
then switch test lead location.
Electrical System (S/N 30101 & Up) (Rev. E)
Brush Length
(New) (Service Limit)
.728" .280"
(18.5mm) (7 mm)
.716" .280"
(18.2 mm) (7 mm)
.728" .197"
(18.5mm) (5 mm)
Field Coil Resistance
2.4 Ohms
3.0 Ohms
2.8 Ohms
Resistance should be infinite in one direction and nearly
zero in the other. If resistance is infinite in both direc-
tions, the diode is open. If resistance is nearly zero in
both directions, the diode is closed. If the diode is open
or closed, replace the recitifer.
BRUSH
LENGTH
(NEW)
HEAT SINK (--)
HEAT SINK (+)
Page 8 - - 18
Rev. G
SERVICE LIMIT
(WORN)
Figure 18
Figure 19
Figure 20
DIODE
DIODE LEAD WIRE
Figure 21
Groundsmaster 580--D