The Washington herald., 1921-10-16
NOISES in ENGINES
AWARNING SIGNAL
TO AUTO OWNERS
Wearing of Parts or Con-
slant Trembling Will
Result in Breakage.
DEMAND ATTENTION
Should Not Be Considered
PASSING Annoyances With
out Serious Import.

One et the greatest enemies Of
the modern motor car is vibration.
The effect Of vibration Is to loosen
the various parts of the mechanism
and the immediate effect of this is
Eel: by the ear of the driver, who
realizes that his car is beginning
10 be the seat OF numberless noises,
which are a far from pleasant ac-
compartment to a drive. But the
noises are only the beginning be-
cause the looseness that causes the
noise, will result in breakage at
no distant date II permitted to con-
tlnue. The car owner, therefore,
should take engine and chassis
noses, not as mere passing an
noyances, but as symptoms of some
thing far more serious and should
earnestly hunt them down, just as
soon as they make their presence
Known We shall try to indicate
what these commoner noises are
ana tell how they may be detected
and eradicated.
We shall begin with the engine
because this is the seat of the
greater part of the unnecessary
noises that seem inevitable in the
operation of the car. The COM
mOnest engine noises are valve
clicks and slaps, both of which may
be detected by the rhythmical reg
ulartty Of their occurrence.
The reason for Noisy gear opera
ton Is too great clearance between
the valve and its seat In the case
OF overhead valves too great a
clearance between litter and push
rod will cause the trouble. The
remedy is obviously the reduction
Of the clearance to the correct
distance and this work should be
done while the engine is heated.
because Of the. expansion of metal
when heated. in which condition the
valves necessarily run.
Occasionally noise in the gear
system Is caused by the litter be-
ing lose in its guide. To locate
sembly will have to be removed A
worn litter will have to be replaced,
though IN certain designs the guides
may be spruns-sIIghtly so that they
will grip, the, litter more tightly
and this remedies the trouble.
Another possible location of noisy
operations is at the cam. between
which and the follower there may
be too much clearance. Fitting
new followers usually takes care
of histtroubls. Worn valve stems
or guidesA Also produce noise. Re
mOval of the springs will enable the
operator to locate trouble at this
point. There should be no side play
of the stem in its guide and If this
condition is found to exist, bush
ings should be fitted in the guide.
or else a new valve with an over
When the valve system is of the
overhead type it is natural to look
for more noise than in the conven-
tionaI type. Adequate fabrication
will do. much to remedy this trouble
with the overhead system. Oc-
Casionally side play develops in the
rocker arms with a slap as a re-
suit. A worn arm bearing also
will make trouble, and the cure i'm
this case Is to mt an oversize bush
ing in the rocker arm.
While the valve system Is the
CommOnest seat of noise troubles
in the engine 1t Is not the sole loca-
ton where this trouble may be
looked for. The bearings in most
engines are Of soft metal. which
must be kept copiously fabricated
or they will burn and fiatten out with
a knock as the result. The ordi-
nary remedy for this is to take UP
the bearing by removing the SHIN
between the two halves, or else to
trim the metal on the movable part
Care must be used in performing
this operation to see that the bear
ing touches the shaft all around
without being too tight.
In fitting bearings the utmost care
-
shaft Is not thrown out OF align
1arly likely to result where one
bearing is taken up without refer
ence to the others In unit power
plant designs, when the shaft Is
thrown out of alignment, of the
shafts in the transmission is sure
TO bind and noisy operation is in
evitable.
Another source of bearing knocks
is found in the hanSs OF she
crankshaft bearings which are fiat
tened by crankshaft thrust. In this
case il does not pay to try and TX
the old bearing flanges: II Is better
simply to get a new bearing.
Play often develops in the upper
rod bearing. and often enough the
car owner blames the lower rod or
crankshaft bearing. On many of
the cheaper cars there Is no bearing
at the top Of the rod. while in GER
tain others a bronze bushing is in
stalled to take up the wear. When
there Is no bushing anew piston pin
will have to be fitted, or II the
piston bosses are. worn eccentric II
NAV mean new piston or the in
stalIation of bushing.
MOTOR FIRM CUTS =