Evening star., 1940-03-31


he Gidn't know where his next car
was coming from.
While 1t Is true that automatic
chokes operate in various ways and
involve such factors as exhaust
manifold heat, carburetor air veloci-
ties, electricity and intake manifold
vacuum. all Of them use thermostats
for the basis control. For that rea-
son it is highly important to use
only an accurate thermometer when
servicing this important unit. There
have been instances where a bad
thermostat got by simply because
the thermometer which was used to
check its temperature was not ac-
curate.
When you are riding along you
may have noticed that in spite Of
the insulation between the engine
and driving compartment many en-
gine smells actually get inside the
car. What causes this? How can
1t be corrected?
Engineers I have consulted on
this point say that because there
is high pressure of air on the nose
Of a modern car there is a partial
vacuum in the body. This sucks in
some Of the air that is exhausting
from the vents in the hood sides and
from under the car. Thus you get
cold air and smells sucking in in
winter; hot air and smells in sum-
mer.
BY using very efficient heater
and air-conditioning unit it is posi-
BILE to blow enough fresh air into the
cars body to overcome this vacuum
effect. That's the main reason you
should consider installing such a
system, even If you are perfectly
comfortable in winter with your
present method of reheating stale
air. II fresh air is drawn from the
front of the car in hot weather,
and you keep the windows closed at
least you won't get engine and ex-
haust odors.
OIL Loss From Valves.
In seeking the reasons for high
oil consumption don't forget that
bad valves have a lot to do with
oil loss. Both oil and air are sucked
past worn intake valve stems and
guides. These are drawn into the
cylinders in quantities such as to
increase the rate of carbon deposit
and to cause poor engine operation
through an excessively lean mixture.
When valves do not seat, the situa-
ton Is similar to loose spark plugs
or to leaky plug gaskets, oil then
being drawn from the crankcase
past the piston rings.
Valves also cause the low oil mile
age indirectly through lowering en-
gine efficiency. This occurs chiefly
when the engine runs too hot
through laboring. Heating is quite
likely to follow if the valves do
not seat tightly. This may be due to
hard particles of carbon on the
valve seats, or to weak valve springs,
warpage, misalignment or to tappet
clearances not being sufficient.
Its just as annoying to have the
brakes start to apply too soon as
to have delayed action, because you
then can't count on normal action
and are apt to miss out in timing
your stopping. Here's what to do
when there isn't enough free travel
OF the brake pedal of a car with
hydraulic brakes:
Since the trouble is due to the
compensation port not opening prop
erly, the trick is to have your service
man loosen the lock nut at the mas
ter piston and turn it in or out so
that 1t has proper clearance when
seated in the master piston"
Sideswiping Is Safer.
One of the best rules to follow
when driving car is to remember
to swing into right turn whenever
collision impends at an intersec-
ton. The two cars then swing into
each other at an angle, causing a
sideswipe if they actually touch. I
have seen some bad smash-ups
averted by this plan. Also should
the cars tend to skid the sideswiping
action counteracts the skidding. 1
happened to think of this plan some
years ago and managed to get
through a bad situation without a
scratch Only the running boards
touched. Which is one of a num-
Der of reasons why I still feel that
the automobile industry will not
abandon running boards universally.
If you don't believe that good rear
springs have lot to do with the
way your car steers don't go arguing
with the front end alignment ex-
pert. but wisely make the simple test
of partially debating the rear tires.
Let them well down for a short test
OF a few blocks. The effect of sag