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Does Coil Adjustment
affect starting? Answer No. 58
Yes. When the vibrators are not properly adjusted more current is required to
make and break the contact between the points, and, as a result, at cranking
speeds you would not get a spark between the spark plug points. Do not allow
the contact points to become "ragged," otherwise they are apt to stick
and cause unnecessary difficulty in starting, and when running they are apt to
produce an occasional "miss" in the engine.
What is the purpose of the Commutator?
The commutator (or timer) determines the instant at which the spark plugs must
fire. It effects the "make and break" in the primary circuit. The grounded
wire in the magneto allows the current to flow through the metal parts to the
metal roller in the commutator. Therefore, when the commutator roller in revolving
touches the four commutator contact points, to each of which is attached a wire
connected with a coil unit, an electrical circuit is passed through the entire
system of primary wires. This circuit is only momentary, however, as the roller
passes over the contact point very rapidly and sets up the circuit in each unit
as the roller touches the contact point connected with that unit. The commutator
should be kept clean and well oiled at all times.
What about
the Spark Plugs?
One is located at the top of each cylinder and can easily be taken out with the
spark plug wrench included with every car, after the wire connection is removed.
The high voltage current flows out of the secondary coils in the coil box and
on reaching the contact points in each spark plug it is forced to jump a 32" gap,
thereby forming a spark which ignites the gasoline charge in the cylinders.
The spark plugs should be kept clean (i. e., free from carbon) and should be
re-placed if they persist in not working properly. There is nothing to be gained
by experimenting with different makes of plugs. The make of plugs with which
Ford engines are equipped when they leave the factory are best adapted to the
requirements of our motor, notwithstanding the opinion of various garage men
to the contrary. All wire connections to spark plugs, coil box and commutator
should, of course, at all times be kept in perfect contact.
What are the indications of Ignition trouble?
The uneven sputter and bang of the exhaust means that one or more cylinders
are exploding irregularly or not at all, and that the trouble should be promptly
located and overcome. Misfiring, if allowed to continue, will in time injure
the engine and the entire mechanism. If you would be known as a good driver
you will be satisfied only with a soft, steady purr from the exhaust. If
anything goes wrong, stop and fix it if possible —don't wait until you get
home.
How can one tell which Cylinder is missing? Answer No. 62
This is done by manipulating the vibrators on the spark coils. Open the throttle
until the engine is running at a good speed and then hold down the two outside
vibrators, No. 1 and No. 4, with the fingers, so they cannot buzz. This cuts
out the two corresponding cylinders, No. 1 and No. 4, leaving only No. 2
and No. 3 running. If they explode regularly it is obvious the trouble is
in either No. 1 or No. 4. Relieve No. 4 and hold down No. 2 and No. 3 and
also No. 1; if No. 4 cylinder explodes evenly it is evident the misfiring
is in No. 1. In this manner all of the cylinders in turn can be tested until
the trouble is located. Examine both the spark plug and the vibrator of the
missing cylinder.
If the Coil and Plug are right— what?
The trouble is probably due to an improperly seated valve, worn commutator,
or short circuit in the commutator wiring. Weakness in the valves may be
easily determined by lifting the starting crank slowly the length of the
stroke of each cylinder in turn, a strong or weak compression in any particular
valve being easily detected. It sometimes happens that the cylinder head
gasket (packing) becomes leaky — permitting the gas under compression to
escape, a condition that can be detected by running a little lubricating
oil around the edge of the gasket and noticing whether bubbles appear or
not.
Does a worn Commutator
ever cause misfiring? Answer No. 64
Yes. If misfiring occurs when running at high speed, inspect the commutator.
The surface of the circle around which roller (see Cut No. 9) travels should
be clean and smooth, so that the roller makes a perfect contact at all points.
If the roller fails to make a good contact on any one of the four contact points,
its corresponding cylinder will not fire. Clean these surfaces, if dirty. In
case the fibre, con-tact points and roller of the commutator are badly worn
the most satisfactory remedy is to replace them with new parts. The spring
should be strong enough to make a firm contact between the roller points if
they are worn or dirty.
Misfiring may also be caused by short circuited commutator wires.
How is the
Commutator removed? Answer No. 65
Remove cotter pin from spark rod and detach latter from commutator. Loosen
the cap screw which goes through breather pipe on top of time gear cover. This
will release the spring which holds the commutator case in place and this part
can be readily removed. Unscrew lock nut; withdraw steel brush cap and remove
the retaining pin. The brush can then be removed from the cam shaft.
Pull Rod Connection Case
Contact Point Brush
Answer No. 59
Answer No. 60
Answer No. 61
Answer No. 63