Generac Power Systems MC - Manual (Page 43)

rotor checks bad in Paragraph A, check Wires No. 1 and 4 for an
open or shorted condition. Inspect brushes - replace if cracked, chipp­
ed or less than 5/16 inch long. Inspect slip rings and clean with fine
sandpaper, if necessary. Make sure brushes are making good contact with
slip rings. Finally, recheck rotor winding resistance at Pins 1 and 4
of white receptacle as outlined in Paragraph A.
RESULT:- Wires, slip rings and brushes
check good but rotor still
checks bad......................................Replace rotor
Wires, slip rings or brushes
check bad............................Repair, clean or replace
TEST 40:-CHECK FIELD BOOST refe?^to^Section^rr)^°'^'^^^ 6897-4
Unplug the Ignition Module to pre­
vent the engine from starting. Al­
so unplug the red connector plug
from its receptacle on the stator
can. Set VOM to ”+DC" and to any
scale that will permit 12 Volts to
be read. Connect the positive (+)
meter test probe to red connector
plug Pin 5, Connect the negative
(-) test probe to frame ground.
Crank the engine - meter needle
should swing upscale and indicate
approximately 9 - 1 2 Volts d-c,
RESULT:- No field boost valtage indicated..... ..... Go to Paragraph B
Field boost voltage checks good.... Continue diagnostic tests
B,)-Unplug connector plugs from
the Printed Circuit Board and from
the red receptacle on stator can.
Set VOM to "+DC” and to "Rxl” sca­
le, then zero the meter. Connect
one meter test probe to Pin No, 2
of the printed circuit board conn­
ector plug. Connect second test
probe to Pin No, 5 of the red con­
nector plug. Meter needle should
swing all the way upscale to zero.
Printed Circuit Board
Connector Plug
Pin No.2
Wire No.4
k -■ Pin No. 5
Red Connector Plug
(On Stator Can)
BOTH CONNECTOR PLUGS VIEWED FROM WIRE END
RESULT:- Meter indicated, zero,... .
Meter did not swing upscale,
.Replace printed circuit board
.Repair/replace Wire No, 4 or
defective connector plug
2.2-21