The evening world., 1917-03-31

sNeomobile Editor; 4
What is the best way to grease the
springs of my car? How often must
1 drain oil from the motor? The
screw Is broken on the crank case and
one half the screw is stll in the case
md 1 am unable to remove II. Would
'ou advise drilling the broken screw
With brace and would that have any
Meet IL the chips should get into the
iston while car is In motion? II. ;.
There are a couple Of appliances
fhioh open the leaves OF the springs
o that oil or grease may bo inserted
etween them. These accessories
ray bo secured at any good supply
tore. Oil should be drained from tho
'otor base at lease every two thou
nd miles. Woud advise drilling
nall hole in the broken screw and
ZEN using a tap which is designed for
lis sort Of work and which has its
Ittinq edges running in the opposite
.reotion. Do not drill the hole
trough the plug entirely,
utomobilo Ditor:
, have driven my car 1000 miles
nd have not as yet fabricated the
brushes from the timer l under
tand that 1t Is advisable to do this,
nd 1 would like to know the best
rade OF oil. JOHN WATSON.
Pure castor oil is said TO be we'll
dapted for this purpose. Before II is
pplied, however, il would bo we'll to
lean out the accessible parts OF the
mer and the brush points with gaso-
ne, and then wipe and dry TO make
ure that no copper dust has accumu-
tied that might form a short circuit.
utomObils Editor:
What is the advantage OF the
-uble spark plug system in which
wo plugs arc used at the same time
A each cylinder? Is not one tat
park in each cylinder sufficient 10
Inlte the charge? Il. G. JOHNS.
Double systems of ignition have
cen used for some years and were
eslgnod to increase the area OF igni-
on. You are correct in assuming
iat a single fat" spark in each
I ylinder will produce satisfactory
ombustion; but tho greater OF the
lumber Of points OF ignition, tho more
apid will be that burning. II must
remembered that what We call an
Explosion" in each cylinder is not an
#xplosion in the strietest sense Of the
.>gtrd, but that IL is a rapid burning
|hat requires an appreciable interval
~ timo-when measured WIN tine
kl,lnutsst Of science. II ignition oe
turs at several points at once, the
sr.ne will not have so far TO travel
40 10 the case when but one spark plug
10 used, and the combustion will be
IproportionateIy rapid in the former
lease. In a large cylinder the effect
Of multiple ignition points is more
notioeable than in a small motor. IN
'prdsr to obtain the advantages OF the
most nearly instantaneous eombus
tion possible, some OF the large cars
In the recent indianapolis Speedway
500 mile race were provided with tour
spark plugs in each cylinder. The
oluus should be set as far apart al
possible, in order that the ignition
area will be properly distributed.
Automoblle Editor;
4 find It rather dificult 20 deter
hine the exact location Of a smal
leak in my radiator. This leak II
probably not larger than pin hole
but the water extends over large
tsurface, due to the capillary action n,
doubt, and I find 1t impossible there
fore, TO determine the exact source
OF the leak. WILLIAM PETERSON
An excellent suggestion has re
Gently been made that what 10 know
as "the plumbers smoke test b
used to settle this difficulty. Thi
consists in pumping smoke into IN
4 radiator and CLOSING all possible exit
except the leak in question IN