The Washington herald., 1921-12-04
Motor Problems
Solved by Cooley,
Motor Authority

Each week in this department.
questions regarding the automo-
bile and its equipment will be
answered. Questions should be
sent to Mr.. e. H. Cooley. vice
president and director of edu-
cation, American Motor Schools,
1821-18c: U street nprthw
They will he answered in this
column Sunday following their
receipt.
Personal attention will he
sladIy extended to patrons of
this column in the event that ex-
plantations here are not thorough
Iy understood. Call At the Amer
lean Motor Schools.
Q. Is II true that spark plug gaps
should be larger on Ford than on
other cars?
A Yes. Better results are obtained
by using slightly larger gaps. This
is due to the fact that all battery
systems require a larger gap. and
the Ford magnetic, generating a
comparatively high voltage on in
creased. speed. would, therefore, re-
quire a gap in excess Of the usual
battery system.
| ~. IAN you SlNc me pTdCliCdl
method of testing various oils with
view of determining which is the
best grade?
A. A number of the oil companies
publish a table which shows the
grade of oil which should be used
on various cars. This is valuable
data to follow. A fairly satisfactory
test for determining oil efficiency is
ha 81
the crank case and flush thoroughly
with about half gallon of the new
oil. Be sure not to use kerosene
for flushing purposes because 1t will
ruin the new oil as it thins 1t to
such a degree as to render it almost
useless. After flushing. fill with
the new oil and keep record of read
ing on speedometer. Note there
after how much oil is added to
maintain the proper level. Before
adding the new oil a test for WIS.,
costly should be made by taking a
quart tin can, making small hole
with nail in the bottom then fill
ing with q quart of the new oil.
Note the length of time that 1t takes
for the oil to drain from the can.
After about 500 miles draw of a
quart Of the oil under test and again
fill the can, noting the time 1t takes
to drain. The decrease in the
length Of time represents the de-
crease in the viscoscity of the oil,
which means that the thinner it be-
comes the less 1t functions as a lu-
bricating agent. The color will in
dictate the degree of carboniZation
that Is taking place. The darker the
oil the greater the carbon deposit.
Q. While driving a Ford car the
other day suddenly without any ap-
parent reason a noise very much
like that caused by a fiat wheel of
trolley car occurred. Will you kindly
tell me what this trouble might be?
The trouble. no doubt, is due to
defective teeth in either the ring or
pinion gears of the differential,
which can easily be determined by
disassembling the differential.
Q. What would be the results OF
using one cord and one fabric tire
on the rear wheels
Undue wear of the differential
would result. This would be done
only in emergency cases, as the diff
ferential will be functining at All
times as 1t does when rounding cor
ners.
@. I have a Ford car which I
have been trying to start for two
days. I know that the ignition is
all right. and that there is gas in
the cylinders, because I prime 1t
| through the spark plug openings.
There appears to be decreased COM
preston on a cuple OF cylinders. Is
there anything / can do to locate
| hA hnf 20 ipO ~
A The diagnosis you give above
sounds very much as though a cou-
pie Of valves might be stuck open.
Remove the valve plate and examine
for this trouble. If you do not
find it to be valves. suggest you re-
move the head and investigate fur
Their.
| Q. There is always a deposit of
oil around the spark plugs on my
car and while car is running there
is a slight bubbling at the plugs.
Does this Indicate any serious
trouble
A. Your engine is pumping oil as
result of piston wear or defec-
tive rings. The trouble is not seri-
Gus only that it is very liable to
cause continual spark trouble. Sug-
gest that you have the trouble rem
cdied as soon as practicable.
Q. Why is it that No. l spark plug
on a Ford car is usually covered
with oil while the others are per-
fectly dry?
| A. This is due to unequal oil dis
tribution which always occurs in
straight splash system as used on
Ford car when descending grades.
In ascending grades the distribution
is less unequal due to the pocket
which surrounds the >flywheel re-
ceiving the excess.
| Q. The other night l stepped on
the starting button and after a
grating noise in the vicinity of~the
| hywheel there was no further evil
dence of effect except that the lights
would grow very dim when l again
stepped on starting button. Il
couldn't crank the car, and was
finally towed into q garage. where
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