1948-1952 Shop Service Manual - - Hudson-Essex-Terraplane Club

6 - 24 ELECTRICAL SYSTEM
Correct ignition timing is indicated by a slight "ping" at
about 15 MPH when accelerating at full throttle from 10
MPH in high gear. If no ping is heard, timing should be
advanced one quadrant graduation mark at a time until the
ping is heard. Under no circumstances should the pointer at
the flywheel opening be more than one inch (first short
mark) before the UDC mark when the spark occurs, Figure
19.
If too much ping occurs or if the engine pings at higher
speeds, timing should be retarded by rotating the distributor
clockwise one graduation at a time.
NOTE: When a change is made from one grade of gasoline
to another, or when the altitude at which the car is operated
is changed considerably, ignition timing should be adjusted
for efficient operation. With premium grade fuels or for
high altitude operation, a more advanced spark setting may
be used.
SPARK PLUGS
Spark plugs used on 232, 262, and 254 Cu. In. engines are
Hudson Champion H-8, 14 mm plugs. Champion H-11
plugs are used on 308 Cu. In. engines. Gap on plugs should
be set at .032". Check gap with a wire feeler gauge and
adjust by bending the ground (side) electrode, Figure 22.
When replacing spark plugs always use new gaskets to
assure correct seal. Seat the plug with the fingers and use a
torque wrench to tighten. Recommended torque is 25 to 30
foot pounds. If a torque wrench is not available, seat the
plug finger tight (on a new gasket) and tighten 3/4 of a turn
with a wrench.
Spark plug condition often indicates other engine trouble
according to the nature and color of the deposit on the firing
end of the plug as shown in the following table:
DEPOSIT
CONDITION
Brown-Powdery Normal Operation with
Tan-Powdery Normal regular fuel.
White-Powdery Normal Operation with
Yellow-Powdery Normal leaded fuel.
Black-Wet Oil Fouled Oil pumping or
plug too cold.
Black-Fluffy Gas Fouled Air-fuel mixture too
rich or plug too cold
White-Blistered Burned Air-fuel mixture too
Electrodes lean, incorrect ignition
timing, leaking valves, or
plug too hot.
HOT AND COLD PLUGS:
FIGURE 22
Spark plugs specified above are for average operating
conditions. If the car is operated under conditions resulting
in consistently high engine temperatures, a colder plug
should be used. If the car operates under conditions resulting
in consistently low engine temperatures, a hotter plug
may be indicated.