Secondary Efficiency Test - Cadillac 54-6219 1954 Shop Manual

11-17
ENGINE ELECTRICAL
7. Adjust the air gap between core andarmature
to .075" with points just touching.
8. Contact point opening with armature down
should be .012" minimum.
9. Turn adjusting screw clockwise to increase
current or counter-clockwise to decrease the cur
rent setting. Make final adjustment by increasing
current setting. Adjust to 30 amperes, andrecheck
with cover in place.
29 Secondary Efficiency Test
This test provides an over-all indication of the
performance of the entire ignition system.
1. Turn coil tester selector switch to secondary
efficiency position.
2. Connect Tachometer leads, as shown in Fig.
11-20.
3. Start engine and set speed at 1000 R.P.M.
4. Ground red positive lead of Coil Tester.
5. Connect the black lead to each spark plug
in turn, and note the reading on the secondary
efficiency scale of the Coil Test Meter.
6. Readings should be in the good band and even
at all plugs.
Secondary efficiency test indications are as
follows:
a. Reverse meter reading off scale to left with
leads connected as in Steps 4 and 5 indicates-coil
of wrong polarity; primary wires reversed at coil;
or battery connected backwards.
b. Uneven reading at plugs indicates defective
spark plug wires or connections, corroded distri
butor cap towers, uneven spark plug gaps, or a
"COCKED" distrihutor nip.
c. Unusually high readings at two or more plugs
indicates a cracked distributor cap or insulation
breakdown between spark plug wires.
d.
Low
reading at all plugs indicates excessive
resistance in either the primary or secondarycir
cuit, or a weak coil.
e. If the reading is unusually low at one or two
plugs, remove the wire from the plug and again
note the reading. If the reading improves with the
wires removed, the plug is shorted out,
30 Cleaning and Setting Spark Plugs
Type 46-5 spark plugs are used on 1954 engines,
and should be cleaned with an AC Model "A" or
"K" spark plug cleaner. The condition of the clean
ing compound is important. Itmustbedry,because,
if moist, the compound may pack in the space be
tween the insulator tip and shell, allowing only the
tip of the plug to be cleaned. Also, the compound
must be sharp to do a good cleaning job. After pro
longed use, the particles of compound lose their
sharp cutting edges and will not clean properly.
With the spark plug in the cleaner and the air
blast turned on, press the cleaner hood down, rock
ing the plug, if the model"A" cleaner is being used.
Raise the cleaner hood to the air blast position for
a few seconds. Rotate the plug in its adapter and
repeat the operations until the entire insulator is
clean white. It should be noted here that some
spark plugs may have fused deposits on the lower
insulator tips that are difficult, if not impossible,
to remove, Make sure that all cleaning compound
is removed from the plug.
The correct spark plug gap for 1954 engines is
Fig. 11-19 Current Regulator Adjustment
Fig. 11-20 Secondary Efficiency Test