505 L4-2155cc N9te (1986)
ALTERNATOR OUTPUT CHECKING PROCEDURE
PRELIMINARY CONDITIONS
Fully charged battery, minimum 12.2 V, specific gravity above 1225 at 80~F
Correct adjustment of alternator belt
Engine at operating temperature and at 3000 RPM
A)
Turn off all accessories - The voltage should be between 13V and 14.8V (at 3000 RPM)
B)
Turn on heated rear window, heater fan, and low beams only (A/C off). The voltage should remain within the bracket of 13V and 14.8 (at 3000
RPM)
INCORRECT READINGS
THE NO LOAD VOLTAGE IS LESS THAN 13V AT 3000 RPM (TEST A)
-
Disconnect wire 7 or 7A (warning light terminal)
-
Apply battery voltage directly to this terminal (on back of alternator)
If voltage is greater than 13V - The energizing diodes are faulty (open)
If voltage is less than 13V - Try with a new voltage regulator
(If the fault persists, replace the alternator)
THE NO LOAD VOLTAGE IS GREATER THAN 14.8V (TEST A)
Measure difference between the voltage at the warning light terminal and the voltage at the output terminal
If voltage difference is equal to OV - Replace the voltage regulator
If voltage difference is greater than OV - Replace the energizing diode or replace the alternator
THE VOLTAGE UNDER LOAD IS LESS THAN 13V (TEST B)
Replace the alternator
