Chevrolet CHEVY VAN G10 SERIES Service Manual page 226

Field Relay Checks and Adjustment
To check for a faulty relay proceed as follows:
1. C onnect a voltm eter into the system at the regulator No.
2 term inal to ground (Fig. 7c).
2. O perate th e engine at fast idle (1500 to 2000 rpm ) and
observe voltm eter reading.
3. If voltm eter shows zero voltage at regulator, check circuit
betw een No. 2 term inal on regulator to " R " term inal on
D elcotron.
4. I f voltage at regulator exceeds closing voltage specifica­
tio n and light rem ains oh, regulator field relay is faulty
(R efer to specifications). Check and adjust regulator as
follows:
Closing Voltage Adjustment
1. Make connections as show n in Figure 9c using a 50 ohm
variable resistor.
N O T E : This gives us a variable resistance in series
fro m a hot lead to the relay coil.
2. T urn resistor to " o p en " position.
3. T urn ignition sw itch off.
4. Slowly decrease resistance and n o te closing voltage o f the
relay. A djust b y bending heel iron in the m anner illus­
trated in Figure 9c.
GENERATOR PULLEY REPLACEMENT
Single Groove Pulley
1. Place 1 5 /1 6 " box w rench on retaining n u t and insert
5 /1 6 " alien w rench in to shaft to hold shaft while re­
moving n u t (Fig. 10c).
Fig. 10c—Pulley Removal
COMPONENT PART REPLACEMENT
Fig. 9 c —Adjusting Field Relay Closing Voltage
Other Harness Checks
O ther wires in th e charging system harness need be checked
for co n tin u ity by use o f an ohm m eter or a te st light (12 V olt).
C onnect the te st lam p so th e wire in question is in series in the
test circuit.
2. Remove w asher and slide pulley fan and spacer from
shaft.
3. Reverse Steps 1 and 2 to install, use a to rq u e w rench
w ith a craw -foot adapter (instead o f box w rench) and
torque th e n u t to 50 ft. lbs. (Fig. 11c).
1 5 / 1 6 " SOCKET
Fig. 11c—Torquing Pulley N u t
ENGINE ELEC TR IC A L 6Y-15
C H E V Y V A N SH O P M A N U A L