Specifications

54
100
Red
Green
DIODE
PROBE (+)
Red
Green
GROUND
PROBE (+)
99
2 and 3 Amp DC Alternator System - Diode
in Harness
Models: H30-35, HS40, H50-60, HH50-60, HM70-
80-100, HMSK, HHM80, HSK, HSSK, LH195, LH318,
LH358 Rotary Mower Engines
This system has a diode included in the red wire which
converts the alternating current (A.C.) to direct current.
The direct current (D.C.) is used to provide a trickle
charge for the battery. The leads from the alternator and
the type of connector may vary, but the output readings
will be the same.
CHECKING THE SYSTEM: Remove the fuse (if
equipped) from the fuse holder and check the fuse to
make certain it is good. If faulty, replace with a six (6)
AMP fuse.
To check D.C. output, separate the connectors at
the engine. Place the probe (+) in the red wire lead
connector. Ground the other probe to the engine (diag.
99).
With the engine running the minimum values should
read:
2500 R.P.M. - 8.0 Volts D.C.
3000 R.P.M. - 9.5 Volts D.C.
3300 R.P.M. -10.5 Volts D.C.
3600 R.P.M. -11.5 Volts D.C.
If these minimum readings are noted, the system is
okay. Check for bad battery, ammeter, wiring, etc.
If less than the above readings, proceed in making an
A.C. output check by pulling back the protective coating
from the fuse holder and diode. Using an A.C. voltmeter,
check voltage from a point between the engine and the
diode as shown in the diagram (diag. 100).
With the engine running the minimum values should
read:
2500 R.P.M. - 18.0 Volts A.C.
3000 R.P.M. - 22.0 Volts A.C.
3300 R.P.M. - 24.0 Volts A.C.
3600 R.P.M. - 26.0 Volts A.C.
If low or no voltage is experienced, replace the
alternator. If the alternator puts out the minimum A.C.
voltage, replace the diode.
www.mymowerparts.com
For Discount Tecumseh Engine Parts Call 606-678-9623 or 606-561-4983