The Brookings register. [volume] (Brookings, Brookings County, S.D.) 1903-1971, 1916-07-06

What clearance 10 allowed aluminium
plstons In relation TO the bore Of the
oylinders7
This Is q quantity which has not as
yet been worked down to standard
practice and varies in the different al
Toys and also varies for different man
u%facturers.
Can you toll me what 10 the trouble
with the two front cylinders on my
oar7 They will run for days and weeks
without any trouble and thsn without
apparent cause will cease firing, the
cylinders flood with gasoline and then
heat up. Tho plugs seem to give good
sparks on every revolution.
Sticking valves would seem to be the
cause for the trouble you mention, as
only the two front cylinders are effect
ed. Probably the motor, becoming
slightly overheated, aus the valves
In these cylinders to stick, resulting In
their failure to admit the charge to the
cylinders at the proper time FOR the
spark to ignite 1t. This also causes the
cylinders to flood with raw gas. You
should look carefully to see that the
valve stems have proper clearance and
that they are not bent In any way.
The immediate cause for the condition,
the ~overheating Of the motor, should
not be ignored. You should 90 over
the cooling system to see that it is
perfectly clean and that all parts are
In good working order. This can be
determined by opening the outlet cock
and running water through the system
by pouring It through the radiator in
let while the motor is running. II the
system Is clogged up in any way so
that the water does not flow through
freely It should be flushed out with a
saturated solution Of common soda.
Although tho diffsrentiai OF my car 10
we'll fabricated, I cannot stop Q singing
noise. What do you suogest7
Probably the pinion on the end OF
the driving shaft Is meshed too deeply
with the crown or master gear Of the
d%ifferential. The noise can be elm
mated by moving the WE gears slight
ly apart. Most cars are equipped with
an adjustment so that the d~ifferential,
as a unit, may be moved from side to
side.
What advantage or disadvantage is
there in having sixteen cams on the
cam shaft Of an eight cylinder motor?
And why do some use sixteen cams
and others eight?
There is no special disadvantage.
Whether there are sixteen or eight
cams In an eight cylinder V engine de-
ponds entirely upon the design Of the
motor. You cannot arbitrarily change
from the use Of eight to sixteen or vice
versa. Where the cylinders are d.
rectly opposite one another and the
valves are in the V, then only n
cam shaft with eight cams can be
used. If the cylinders are offset so
that the side by side method Of con
Meeting rod attachment can be used,
there must be an individual cam for
each valve, or sixteen altogether. AS
compared with the cam shaft with
eight cams, the type with sixteen Is
not quite SO simple. but that Is not
anything for the cal owner to trouble
about one way or the other. It fs a
matter Of manufacture. On the other
hand, the connecting rod lower end
construction is slightly more compli-
Gated where the cam shaft with eight
cams Is used, so that one design about
balances the other In advantages or
disadvantages.
10 there any way Of determining what
gear ratio on final drive would prove
most satisfactorily
The gear ratio which Will prove most
satisfactory depends upon what speed
you wish to get out Of the a with
certain size wheels. Suppose you want
the car to show a maximum speed Of
forty-fve miles per hour when the mo-
tor is operating at its maximum speed
and power. Then, knowing the wheel
size, you al use a gear reduction
which win give this result
have had three now cars burned up
and would like to have the following
question answered., Would the gears
in cars burned nave to be case hard
etS0 OV0F OF COuto tn0y Do 0ooo 10
they are? II they need case hardening,
whore could I get IL done?
The gears in these cars are prob
ably all right. AS they are all inclosed,
the heat would have to go through the
housings before reaching them, and
1t Is not likely that they have lost
their hardness. Any mechanic who is
experienced can determine their con-
dition by filing them slightly. A soft
piece Of metal will reveal itself to a
good file. Case hardening Is done In
many plants, nearly every city Of any
size having factories where such work
Is carried on. 1t would probably be
just as cheap. however. to replace the
gears as to trouble with such rehard-
ening Of damaged ones, and, besides,
there would be considerable expense
attached to It. In any case It would
be advisable to use the gears as they
are, later replacing any Of them that
might prove to have been damaged.
Should valves in exhaust and intake
bo OF the same material?