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6
Chapter I-General Engine Repair
drive. In rare cases, the starter drive may lock up with
the flywheel. This can be corrected by loosening the
starter and releasing the starter drive. If the starter does
not operate, remove it and make the necessary repairs.
(2) ENCINE CRANKS, BUT JJ?ILL NOT START.
The most probable cause of this trouble is a defect in
the ignition system. The next most likely cause is a
malfunction of the fuel system. A simple check will
determine which system is at fault. Remove one wire
from a spark plug, and insert a piece of proper sized
drill rod so that it will protrude from the insulator. With
the ignition on and the starter turning the engine over,
hold the end of the rod approximately o/t 6-inch from the
block.
If
no spark is obtained, check the ignition system.
If a good spark is obtained, check the fuel system.
(a) No SPARK.
If
no spark was obtained, follow the
steps below to determine the cause and make the neces-
sary repairs or replacements.
(1) Pull the coil wire from the top of the distributor.
Hold the wire o/ts-inch from the cylinder head, and with
the ignition on and the engine turning over, see if there
is a spark. If there is a good spark, the trouble lies in
the distributor cap, rotor, or spark plug wires. Make
sure these components are clean, dry, and not defective.
Repair or replace them as necessary.
(2)
If
there was no spark in (1) replace the high
tension wire between the coil and distributor and check
again. If a weak spark exists, the points are probably
arcing. Replace the condenser and adjust the points.
If a weak spark persists, test the coil.
(3) If there was no spark in (2), remove the dis-
tributor cap and see if the points are opening and that
there is an electrical charge to the points. Adjust or
replace as necessary.
If
there is current at the points,
and they open properly, the secondary circuit of the
coil is defective.
If
there is no current at the points,
install a "jumper" between the "Dist" terminal of the
coil and the distributor, and check for current at the
points.
If
there is current replace the wire.
If
there was
no current, install a "jumper" between the two coil
terminals and recheck. Replace the coil if current now
exists at the points.
If
not, install a "jumper" from the
battery to the ignition wire side of the coil, and check
for current at the points.
If
there is current, the ignition
switch or wiring under the instrument panel is defective
and must be repaired or replaced.
(b) WEAK SPARK.
If
the spark test at the spark
plug showed a weak spark, perform the following checks
in the order listed:
( 1) Test, recharge, or replace, the battery.
(2) Remove the distributor cap, and check the con-
dition of the points. Adjust, clean, or replace them as
necessary. Severely pitted points are usually an indica-
tion that the condenser is permitting arcing, and it
should be replaced.
(3) Check the condition of the rotor, distributor
cap, and plug wires. The wires must be clean, dry, and
must be fully seated in the terminals. Replace as neces-
sary.
( 4) If the weak spark persists, the coil should be
tested and replaced if necessary.
(c)
GOOD
SPARK. If a good spark was observed,
check the fuel system as follows:
(1) Check the fuel supply at the fuel tank. Do not
attempt any other fuel system checks before doing
this.
(2) If there is fuel in the tank, check to see if it
is reaching the carburetor. Remove the air cleaner, and
look down the carburetor throat while working the
throttle by hand. Each time the throttle is worked, a
spurt of gasoline should be emitted from the accelerator
pump discharge nozzle.
If
there is fuel at this point,
the engine was probably flooded or there is water in
the fuel system.
(3) If no accelerator pump discharge is observed
in the carburetor throat, loosen the fuel pump to fuel
tank line at the fuel pump. Remove the fuel tank filler
cap.
If
fuel runs out freely, the line is clean.
If
not,
blow the line out by air pressure from the fuel pump
end.
NOTE: Check the flexilJle gas line for a collap&ed
condition.
( 4)
If
the cause of the trouble has not been found,
check the fuel pump pressure, then repair or replace
the fuel pump or carburetor.
(3) ENGINE STARTS, BUT FAILS TO KEEP
RUNNINC. The most probable cause of this malfunc-
tion is the fuel system. The ignition system sometimes
can cause trouble, but it is usually after the engine has
run for some time and is at operating temperature. In
either case, check the fuel system first.
(a) Check the fuel supply at the gas tank.
(b) Try to start the vehicle.
If
it will operate with
constant foot throttle, adjust the idle speed and check
the choke adjustment.
(c) If it will not operate with constant foot throttle,
remove the air cleaner, and check to see if fuel is
getting to the carburetor. This is done by looking down
the carburetor while operating the throttle.
If
gasoline
is observed spurting from the accelerator pump dis-
charge nozzle, the engine was either flooded or the fuel
system has water in it.
( d)
If
no accelerator pump discharge is observed
in the carburetor throat, loosen the fuel pump to fuel
tank line at the fuel pump. Remove the fuel tank filler
cap.
If
fuel runs out freely, the line is clear. If not, blow
the line out with air pressure from the fuel pump end.
NOTE: Check the flexillie gas line for a collapsed
condition.
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