John Deere 318 - Manual (Page 346)

4a
Alternator Test
For Unregulated
Output
M37209 -UN-25JAN90
NOTE: The specifications listed in the table
below are the approximate maximum VAC output
of unregulated stators used on the “P” series and
“B” series engines.
Disconnect stator leads (A) from regulator.
Start engine and run at full throttle (approx. 3450
rpm).
Connect voltmeter to stator leads (A). Compare
reading with specification (listed in chart) of
engine being tested.
NOTE: If stator AC voltage is at least twice the
specified battery DC voltage, stator is probably
okay. Perform resistance and continuity tests if
stator is still suspect.
The “Spec” letter is the last letter of the engine
model number.
“P” SERIES ENGINE VAC OUTPUT
(P218G and P220G)
Spec “A” . . . . . . . . . . . . . . . . . . . . . . 28—41 VAC
Spec “B” and “C” . . . . . . . . . . . . . . . . 28—57 VAC
“B” SERIES ENGINE VAC OUTPUT
B43E . . . . . . . . . . . . . . . . . . . . . . . . 28—40 VAC
B43G and B48G . . . . . . . . . . . . . . . . . 28—31 VAC
NOTE: A stator shorted
to ground may produce
VAC output that’s within
specification, but
produce below specified
VDC when stator is
connected to regulator. Key switch OFF.
Stator leads
disconnected from
regulator.
Check each stator lead
for continuity to ground. CONTINUITY TO
GROUND: Replace
stator.
NO CONTINUITY TO
GROUND: GO TO
4b
MX,159024030,14-19-17MAY95
Electrical System Component Tests and Adjustments/Alternator and Regulator/Rectifier Tests
TM1590 (17MAY95)
240-25-6
316, 318 & 420 Lawn and Garden Tractors
020895
240
25
6