The Twin City star. [volume] (Minneapolis, Minn.) 1910-19??, 1915-05-01

How oan one tell when . magnetic
nesds rennagnetixlns7
When the magnets will not lift and
hold about fifteen pounds they are
said to be weak. Missing fire at low
speeds is the result Of weak magnets.
Wlcn this occurs the magnets should
be recharged
! WHIST are tho respective advantage
and disadvantages Of ths T head and
L head typsssof motorsf
The T head motor, because it's valves
are located on opposite sides, allows Of
the use of large valves, and hence more
power is obtainable than In the L head
variety, other things, of course, being
equal It is usually more costly to con-
struct, than the L head type and has
more symmetrical. appearance. The
+ head, however, Is heavier and more
complicated than the l. head design,
the latter using only one cam shaft and
having the valves all on one side.
What arc the advantages and dis.
advantages Of tho valve In the head
motor7
The chief advantage claimed for the
valve In the head motor Ia that, for
given size, It has more power than an
L head or T head, because Of the fact
that larger valves may be used and
the combustion chamber given q more
spherical shape. There are a number
Of manufacturing advantages. one Of
which is that the entire combustion
chamber may be machined and given a
high polish, thus preventing, to great
extent, the accumulation Of carbon.
The loss of heat through the cylin-
der walls Of a motor depends to a great
extent upon the surface Of the walls,
and in properly designed valve In the
head motor this wall area Is small,
compared with that of another type of
motor Of the same size. This reduc-
ton Of wall area IL. obtained because
Of the absence of valve pockets
The main disadvantage of the valve
In the head motor, especially one using
valve cages, Is that the valve seats can
not be cooled as effectively as If the
seat were a part Of the casting. This
is true in the cage construction, BE-
cause the heat, In order to get from
the valve seat to the water jacket,
must overcome the resistance of the
joint between the cage and the cylin-
der casting. This Lack Of cooling would
not materially affect the inlet valves,
as they are kept comparatively cool by
the incoming gas, but it would mean
more valve grinding In the case Of the
exhaust valves
10 Il possible to maintain pressure In
q rear fuel tank when the tank Gap 10
mIssing7
In cases Of this sort take an old in
ner tube, cut out piece about eight or
ten inches long, tie one end tightly, 50
as to be air tight, then insert the tied
end into the tank. Next remove the
valve connection from the pump, In
sert the hose in the open end Of the
tube and pump until the tube COM
pletely fills the hole In the tank. Then
tie the outer end securely. This con-
trivance will hold several pounds pres
sure In the tank and will last for some
time.
L. thres-eisttFIs Of an inch too much
play -ins the wrist pin bushing7
Three-eighths- Of an. inch is entirely
too much play for the wrist pin BUSH
ing, assuming that up and down play
is meant There should be 90 little
play that it cannot be felt by q move
ment Of the wrist pin
Can I sifverize glass rsfieotorsf ~
90, what are the ingredients and In
whats ropertions are they usedf
An amateur can silverize refectors,
but It Is very difficult to make q good
Job Of It. The method by which this
work has been carried out f. an fol-
lows: First fasten to a block Of wood
the finest possible grade Of emery
cloth. With this the reflector is
smoothed down to fine finish. It is
next necessary to have a. melting pot
and q thermometer which Is capable
Of measuring more than 212 degrees.
Two ounces Of lead, two ounces Of tin
and four ounces Of chemically pure
bismuth are melted together. Eight
ounces Of mercury are added at PIP
degrees r. and mixed with the melted
mixture. This Is applied while warm
with smooth camels hair brush.
Which will give the. better results,
90 or "a test sasoIins2
As between 90 and "a test gasoline,
the 60 test fuel has been found to give
the best results as far as mileage Is
concerned. The gasoline which we get
nowadays Is much heavier than that
on the market, say, I've or ten years
ago.
Can an expert gain any advantage
by changing from automatic to hand
control in a battery ignition system3
A skilled driver might get better re-
suits with a hand control Of the
spark than could be obtained with
the automatic type Of ignition control
for the reason that grade climbing can
be accomplished much easier and the
loads Of the motor considered. In 9TH
or words the driver can shift his