Evening star., 1926-05-09
No. 14s. ou,wittius Car Trouble,

IT was only failing stop-light. but
II served. to start Smith asking ques
tions that brought valuable informa
tion. This was the third time within
the year that signal bulbs had gone
bad, and he was beginning to suspec'
the garage hands.
His better judgment prevailed, how
ever, for within a short time he had
figured ont Just why 1t happened anO
why such bulbs would continue &c
wear out at an abnormal rate. Every
time | step on the brakes this sigma
light flashes" he reasoned. Il drive
a great deal in traffic. Besides 1t Is
fla ashing Il bulb that shortens its life
in addition, there is considerable VI
bration and Earring where the signal
device is attached"
That settled that. Smith decided &c
run over a number of other problems
and see If he couldn't reason out the
answers Just as we'll
Tho first thing that came to mind
was the annoying rattle he had heard
for some time. Time and time again
he had jumped out and rearranged the
tools in the trunk on the rear of the
car, thinking that something might be
free to bounce around. The noise was
like a wrench tapping against the in
side Of the trunk, but a short spin
with the tools removed altogether
proved that this could not possibly be
the case.
This Experiment Helps.
In line with good practice, he de-
cided to have the car creased all over.
This would eliminate the possibility
of the noise coming from anything
needing lubricant. And the expert
ment could not be anything but help
full TO the car.
What Smith found was that the rear
universal joint needed grease. 1t was
slightly worn, and without grease TO
act as a shock absorber 1t ratified and
knocked, depending upon road and
driving conditions.
The next thing that attracted his at
tention was the ammeter pointer
which showed about three ampereS dis
charge even with lights and ignition
off. For n time he figured this might
mean a discharge back to the gene
rator, recalling that the relay points
sometimes stick together when they
should be separated as a protection
against battery discharge to generator
when the engine isn't running. He
had worried about 1t all that day, In
tending to consult Il repairer at the
first opportunity.
Now 1t was simple enough. A dis.
charge back to the generator would
have shown up on the ammeter with a
wide swing to the right, just as when
the ignition is turned on. A short cir
cult anywhere would have blown out
q fuse. There was only one other SO
luton: The indicator on the ammeter
was thrown off center, strain result
ing from rough riding.
Studying the Mechanic.
Progressing so nicely Smith gave
some thought to the views of q me.
chanic who proposed to make a quick
Job OF cleaning out the carbon without
touching the valves. The mechanic
had said that he would glance at the
valves and IL they didn't look bad
would not take the time to grind them,
saving this for a later job when car
bon had accumulated again.
How will he be able to tell whether
the valves need attention." Smith
asked himself "All he will see are
the valve seats. Perhaps these ma Y
be in good condition, but what of the
stems, Suppose they are worn? How
could he. Ihake decent ad1ustn1ent
Of the tappetsnnd how could T. expect
to have a quiet running engina2'' 2