Service Manual

11
10
CHARGING SYSTEMS
40 AMP CHARGING SYSTEM
Fig. 1 shows wiring diagram for 40 amp charging
system.
The 40 amp charging system consists of a belt driven,
internally regulated alternator, Fig. 19.
The alternator contains a charge light circuit (“L”
terminal). With the keyswitch in the ON position and
the engine not running the charge indicator light should
light. With the engine running the light should go out,
indicating that the battery is being charged.
If the charge indicator light does not light when the
keyswitch is in the ON position (engine not running),
check the bulb and wiring.
Note: A loose V-belt will cause low DC output.
Belt deflection limit is 9.5-11.5 mm/10 kg
(3/8-7/16 in./22 lbs.).
Fig. 19 – 40 Amp Alternator
“IG”
TERMINAL
“L”
TERMINAL
“B”
TERMINAL
TEST EQUIPMENT
The digital multimeter, Tool #19464 and the DC shunt,
Tool #19468, Fig. 20, are required to test the charging
system.
Note: The digital multimeter will withstand DC
input of 10-20 amps for up to 30 seconds.
To avoid blowing fuse in meter, the DC
shunt is required.
Replacement fuse is available from your Briggs &
Stratton source of supply. Order Part No. 19449.
Fig. 20 – Test Equipment
19464
19468
TESTING ALTERNATOR – DC OUTPUT
The DC Shunt must be installed on the negative (-)
terminal of the battery, Fig. 21. All connections must be
clean and tight for correct amperage readings.
Attach meter test leads BEFORE starting engine.
The regulator-rectifier test will be performed with the
meter in the position.
1. Attach RED meter test lead to RED post terminal
on shunt.
2. Attach BLACK meter test lead to BLACK post
terminal on shunt.
3. With the engine running at 2000 RPM, the output
should be:
* 4 – 20 Amps
* Depending upon battery voltage and/or current draw
on system.
4. If no or low output is found, be sure that all
connections are clean and secure.
5. If all connections are OK, replace or repair the
alternator.
Fig. 21 – DC Shunt Installation
BLACK
LEAD
RED
LEAD
NEGATIVE
BATTERY
TERMINAL
ATTACH NEGATIVE
BATTERY CABLE