Chevrolet CHEVY VAN G10 SERIES Service Manual page 231

ENG INE E LEC TR IC A L 6Y-20
c. T urn th e adjusting screw clockwise (Fig.
th e lam p lights, th en give the w rench
opposite direction (counterclockw ise) to obtain the
proper dwell angle.
DISTRIBUTO R CONDENSER
Performance Diagnosis
The follow ing four factors affect condenser perform ance,
and each factor m ust be considered in making any condenser
test.
1. Breakdow n—A failure o f the insulating m aterial. A direct
short betw een the m etallic elem ents o f the condenser.
This prevents any condenser action.
2. L ow Insulating Resistance (leakage)— Low insulation re­
sistance prevents th e condenser from holding a charge.
All condensers are subject to leakage w hich, up to a
certain lim it, is not objectionable.
3. High Series R esistance—Excessive resistance in the con­
denser circuit due to brok en strands in the condenser
leak or to a defective connection. This will cause burned
points and ignition failure u p o n initial starts and at high
speeds.
4. Capacity— C apacity is determ ined by the area o f the
metallic elem ents and the insulating and im pregnating
materials.
For a com plete check o f the condenser, use a tester w hich
will check fo r all o f the above conditions. Follow th e instruc­
tions given by th e m anufacturer o f the test equipm ent.
Condenser capacity should be .18-.23 m icrofarads.
Replacement
Six Cylinder Engine Distributor (Fig. 1i)
1. Release distributor cap hold-dow n screws, remove cap
and place it o u t o f the w ork area.
2. Remove ro to r and dust shield.
3. D isconnect condenser lead wire from co n tact point
quick-disconnect term inal.
4. Rem ove condenser attaching screw, lift condenser from
breaker plate and w ipe breaker plate clean.
5. Install new condenser using reverse o f procedure outlined
above.
Eight Cylinder Engine Distributor
1. Remove distributor cap and ro to r.
2. D isconnect condenser lead (Fig. 2i) from term inal.
3. Remove screw holding condenser bracket to breaker
plate and slide condenser from bracket.
4. To replace condenser reverse th e above procedure.
N O T E : Make sure that
installed in proper position (Fig. 2i).
Distributor—Removal
1. Release the d istributor cap hold-dow n screws, remove the
cap and place it clear o f the w ork area.
6
i) until
1/2
tu rn in the
new condenser lead is
N O T E : If necessary, remove secondary leads from
the distributor cap after first marking the cap tower
for the lead to No. 1 cylinder. This w ill aid in the
reinstallation o f leads in the cap.
2. Disconnect th e distributor prim ary lead from the coil
term inal.
3. Scribe a realignm ent m ark on the distributor bow l and
engine in line w ith the ro to r segment.
4. Disconnect external connections (vacuum line, drive
cables, etc.) remove the distributor hold-dow n b o lt and
clamp, remove the d istrib u to r from th e engine. N ote
position o f vacuum advance m echanism relative to the
engine.
C A U T IO N : Avoid rotating the engine w ith the
distributor removed as the ignition tim ing w ill be
upset.
Disassembly
It is advisable to place the d istrib u to r in a distributor
testing m achine or synchroscope prior to disassembly. When
m ounting distributors for tests, first secure th e gear in the test
drive m echanism , th e n push the d istrib u to r housing dow nw ard
tow ard th e gear to take up any end play betw een the gear and
the housing.
Test th e d istributor for variation o f spark, correct centrif­
ugal and vacuum advance and condition o f contacts. This test
will give valuable inform ation on distributor condition and
indicate parts replacem ent which m ay be necessary. Check the
area on th e breaker plate ju st b en eath th e co n tact points. A
smudgy line indicates th a t oil or crankcase vapors have been
present betw een the points.
Six Cylinder Engines
Refer to Figure 7i.
1. Remove the ro to r and dust shield.
2. Remove th e vacuum control assembly retaining screws,
detach the u n it from th e distributor housing.
3. D isconnect th e prim ary and condenser leads from the
co n tact p o in t quick disconnect term inal, remove the
co n tact p o int set attaching screw, condenser attaching
screw. Remove the point set and condenser from the
breaker plate.
4. Remove the breaker plate attaching screws, remove the
breaker plate from th e d istributor housing (Fig. 7i).
N O T E : Do not disassemble
further.
5. Remove the roll pin retaining the driven gear to the
m ainshaft, slide the gear from the shaft.
6
. Slide the cam and m ainshaft
housing.
7. Remove the weight cover and stop plate screws, remove
the cover, weight springs, weights and slide cam assembly
from the m ainshaft.
breaker plate any
from the distributor
C H E V Y V A N SH O P M A N U A L