The Brookings register. [volume] (Brookings, Brookings County, S.D.) 1903-1971, 1915-10-07

Ny engine seems to backfire or isnit'
the charge as il goes into the cylinder
The spark plugs have been out recently
and are in good condition. The bat
teries are new and the breaker points
are set up as close as necessary in ordeI
to give a good spark at the plugs. Wha'
10 the cause Of the backfirins and tn,
remedy?
1t appears to be a case OF a carbon
lied motor. Mistirlng and o~verheatins
usually are good indications that there
is a carbon deposit on the cylinder heat
and piston. Small %protruding particles
Of this carbon become red hot AM
ignite the charge the moment 1t enters
the combustion chamber. When the
car Is moving rapidly the misirine
may not be so aggravated, but when
operating slowly or possibly idling the
misfiring Will be In evidence. Check
up on the carburetor adjustments. Al.
though carbon will cause heating, a
rich mixture will show the same re,
suits.
Which give the more power, light or
heavy pistons7
Lighter pistons are better than heavy
ones for obtaining more power.
My car has 3Na by 34 bore and
stroke. What effect would it have to
put a one eighth inch plate on tho end
Of the ~pistons2 Would one-fourth inch
be too much? Would putting one
eighth inch plate between the cylinder
and crank case and one-fourth or three
eighths on the end of the piston increase
the power any appreciate amount?
By attaching n plate to the top of the
pistons you would decrease the size OF
the effective combustion space and
thus increase the compression and
power. By shimming up the cylinder
casting you would tend TO do just the
op~posite-that is, you would increase
the size Of the combustion chamber
and thus decrease the compression and
power. A one-fourth inch plate would
be too thick. If you use any at all
take a one-eighth inch plate Of light
material, such as aluminium alloy.
You would put extra strain on the
parts by increasing the compression,
but the motor you have can stand a
little excess.
ls there any harm in shifting gears
over railroad tracks or rough roads7
Gear shifting while crossing railroad
tracks Is poor practice for the reason
that the engine may be stalled and diff
fculty had in starting 1t again. Many
fatal accidents have occurred because
Of the engine stalling on the tracks.
There is no harm done TO the mechan-
ism In shifting either on the tracks or
rough roads any more than there Is In
shifting on good roads.
MY car skips every time the throttle
10 changed, and no mount Of adjusting
will stop IL. had the car torn down
and thoroughly ov~erhsuIed, but the car
buretor 10 still troublesome. What can
| dof
The first test you should make Is to
ascertain whether or not you have any
leaks around the intake manifold
that i, between the engine and the
manifold and also between the mani
fold and the carburetor. When the car
is running idle see that there Is no
gasoline leaking.
Should you find that there are no
le@k e n In dyfgah la fhat yn, rSa n m
exhaust sleeve or drum around the ex-
haust manifold flexible tube running to
the air bend in the carburetor, as by
using this hot air you are able TO keep
the heavy gas from precipitating on
the walls OF the manifold and from
running back to the carburetor when
the car stops. With the extremely
heavy gasoline which we are now get
ting. In order to assist In the vaporiza-
ton and to hold this heavy gasoline In
suspension, 1t is desirable to use hot
air through the low speed air opening.
II these adjustments are followed and
there are no leaks there should be no
further trouble.
How often should the crank case be
drained and cleaned out with gasoline?
With a new car this should be every
300 or 1000 miles. and thereafter ev-
cry 1900 miles will be sufficient.
Does IN overhead valve motor give
power than q T or L head? L.
possible 70 get more miles per gallon
out Of Cas with an overhead valve mo.
tori
II Il claimed that a valve In the head
motor Of q given size. weight and man.
ufacture gives more power than an l.
head or T head of the same size. weight
and manufacture. However, this Is not
always true. It IL difficult to get two
motors In L bead or T head and a
valve In the head which show the same
design with the exception of the valve
arrangement. 1t is possible that a T
head motor Of a certain size has more
power than q valve In the head Of the
same sixN, owing perhaps to the intake
manifold design. the bearing design
and weight Of the various reciprocal
Ing parts, etc. In order to answer your
question definitely It would be neces-