Specifications

46
Check for a defective ammeter, wiring, etc. If less
than the above readings, disconnect the plug from
the regulator-rectifier, and insert the A.C. voltmeter
probes in the two outside terminals (diag. 87).
With the engine running the minimum values should
read:
2500 R.P.M. - 12.0 Volts A.C.
3000 R.P.M. - 14.0 Volts A.C.
3600 R.P.M. - 18.0 Volts A.C.
If the minimum readings are noted, the regulator-
rectifier is defective. If less than the above readings,
the alternator is defective.
A.C.
87
In this system, the regulator and rectifier are
combined in one solid state unit mounted under the
blower housing of the engine.
Various types of regulator-rectifiers have been used
on different applications. Test procedures for all
types are the same. However, regulator styles are
not interchangeable (diag. 88).
CHECKING THE SYSTEM: An open circuit D.C.
voltage check cannot be made with this system. If a
known good battery fails to maintain a charge,
proceed in making an A.C. voltage test.
To do this, the blower housing must be removed,
and the regulator-rectifier must be brought outside
of the blower housing.
Keep the A.C. leads attached to the regulator-
rectifier. Install the blower housing with the regulator-
rectifier outside the housing. With an A.C. voltmeter
probe the regulator as shown (diag. 89).
CAUTION: AT NO TIME SHOULD THE ENGINE
BE STARTED WITH THE BLOWER HOUSING
REMOVED.
With engine running, minimum A.C. voltage from
lead to lead should be:
2500 R.P.M. - 16.0 Volts A.C.
3000 R.P.M. - 19.0 Volts A.C.
3300 R.P.M. - 21.0 Volts A.C.
3600 R.P.M. - 23.0 Volts A.C.
If the minimum readings are noted, the alternator is
okay. If the system fails to charge a known good
battery, the regulator-rectifier must be defective.
88
89
D.C. OUTPUT LEAD-RED
MAGNETO GROUND - GREEN
A.C. VOLTMETER
YELLOW
RED
INSERT PROBES INTO
CONNECTOR SLOTS. DO
NOT REMOVE
CONNECTOR WIRES
CAUTION: BLOWER
HOUSING MUST BE
INSTALLED WHEN
RUNNING ENGINE
7 Amp Alternator System Regulator-Rectifier Under Engine Block Housing, Models:
H50-60, HH50-60, HM70-80-100, HHM80, TVM125-140-170-195-220