Aberdeen herald. [volume] (Aberdeen, Chehalis County, W.T.) 1886-1917, 1917-04-06
Will you please explain what ID
meant by back firing?

Will you please explain what 10
meant BY back firine7
Back firing usually implies that igni-
tion takes place In the cylinder before
the piston reaches the dead center Of
the compression stroke, thereby caus-
ing the crank shaft to reverse. II this
occurs when the operator Is holding
the crank 1t produces q back kick
which Is liable to dislocate the shout
der or otherwise injure the arm.
The term back firing is also applied
to an explosion occurring in the cylin-
der during the inlet stroke Of the pis-
ton. This would ignite the gas In the
intake manifold and mixing chamber
Of the carburetor. Should gasoline be
near the carburetor it may cause q Sc
rious fire.
viii you please explain why valves
arc reeround by alternating rotary mo.
ton in view Of the fact that valve tap
pets are arranged to give tho valves
slightly continuous rotary motion in
service? Also, what are the objections
to the continuous rotary motion in re-
grinding?
Valves are ground by an alternating
rotary motion to avoid scoring the
seats or the valves themselves. You
know that If you were sandpapering a
finely finished piece Of wood, such as
an automobile body, preparatory to-
painting 1t you would not draw the
sandpaper around in continuous path,
for that would leave ridges or scratches
The same applies to grinding in valves
Can you tell mo tho best method Of
cleaning leather upholstery
The best thing to apply to the up
hOlstery IL you would preserve its soft
ness and keep 1t from cracking Is q
good leather dressing preparation.
There are a number of good ones on
the market. Water in which there Is q
little ammonia Is also a good leather
cleaner, and after using 1t soft cloth
should be employed to rub the sur.
face of the leather dry.
What causes gasoline to drip from
my carburetor for a few seconds after
stopping tho motor7
Probably the float is not adjusted
properly.
Do evsrsizsd pistons tend to mako .
motor heat7
Yes, If they are so tight that they
are stiff and create too high compress
sion. If they allow the proper clear
ance they do not overhead the motor.
When removing . storaee battery, u
the generator Wires Wero connected,
why would noe that prevent The wind.
inss from burning eut'
Because II the generator Il passing
current through itself without any out
let the voltage builds up rapidly and
ct high speeds 1t can reach the point
where the windings viii be burned.
II change q one and one fourth inch
earburstor 60 q one and ons.haK will
u inerease spssd without making the
intake manifold Iarssr3
This depends entirely on how well
the present size Of carburetor and size
and design Of manifold are adapted to
the engine in question. Ordinarily
when the carburetor for touring Is re-
placed by one Of larger size more speed
results.
Why is the distance between the front
wheels Of a car greater at tho top than
at the bottom?
The reason for this is to make steer
ing easier. The object of tipping the
wheels in this manner is to bring the
point Of contact between the wheels
and the ground in vertical line below
the axis of the steering knuckle. When
the line of the center of the steering
knuckle produced is coincident with
the contact of the tire and the ground
there is no tendency for the wheel to
be thrown out of line when an Obstruc-
ton is met on the road. On the other
hand, were this point to be somewhat
inside of the point of contact of the
wheel and the ground there would be a
tendency for the wheel to be turned
about the steering knuckle whenever
an obstruction was met, with the re-
suit that there would be an interfer-
ence with the steering.
How can tell whether my motor is
timed correctly? When cranking the
motor slowly with the spark advanced
it kicks back. Does this show that it
is properly timed?
Your motor is probably timed cor
rectly. If you wish to check up on
the timing set the spark at fun retard
and the piston of No cylinder at top
dead center. Then examine the break
er box mechanism. If the points for
No. l cylinder are just ready to break
the timing is correct.
| have recently noticed a jump in my
car w en- oPen the throttle with a
load on the engine. Il seems as though
tie clutch sips out and in again, grab
bing suddenly and producing the jump.
Can you advise me regarding thls?
The diagnosis which you have made
of your own case seems to fit the evil
dence you have given regarding the
action of your car. The clutch does
not slip out, however, but remains en-
gagged when occurrences such as you
have noted take place. What actually
happens is that the surface of the
clutch is in such a condition that the
fractional resistance is not sufficient to
hold the load II you have leather
faced cone clutch the chances are that
the leather has become dry and after
q It.lKx 4, lon !,