Richmond times-dispatch. [volume] (Richmond, Va.) 1914-current, 1919-01-26
6|B|PL|F|ED LESSONS IN
CARE OF AUTOMOBILES
Multiple Cylinder Engines interest
ipglN Described by EN-
pert GucrrIich.
HOW 10 FIND FIRING ORDER
Working OF Twin-Sixcs Demonstrated.
s sucstions OF Car Owners Answered
IN Language Clear TO Laymcn.
OF Drivers Explained.

sss..Ail the cylinders OF a tour-cyclc en-
sS.ne tand practically all automobile en-
Ssaes arc four-cyclc ens!nes) no mat
Ter how many cylinders ii may have,
Ore. while No. ] cylinder goes through
It's cycle; that is. suction. compression,
8 hit1ins or power. and exhaust.
AS each OF The above strokes take
& place during c-half revolution. tho
senennpscte cycle requires two revolutions
4 ~ the crank shaft.
There being four cranks in tour
{SaSiinacr engine. these cranks mus. be
tIne 5nalf OF revolution apart. or rhcrc
3 SefnS $50 degrees IN u circle so de-
I sTecs apart.
q In tho six-cyiinder. however six
SnSlinders fire in TWO revolutions or
riJnrec in one revolution, thus the u-anks
a aso be one,,hird OF = revolution OF
Shaft is shown in Fig. ].
r:Note that IN this crank shaft crank
pihS anu e, . and =. aud and 4. are
In llnc' and therefore pistnns and 8,
~ and ), or and 4, must be an to-
Eether Noticing tina; those all ed.i
lS SEVEN VIII hclp YOU 10 rcmemtcr the
Sombinaticn.
~ While there are a great many posi-
afie hrinS orders for a siN. the us,ia!
cnes are either 15-3-6-.-4 or Lee
y rou can check up the firing Order
You bave found. as explained in the
Isst lesson. by seeing il when the fir.,
,nFee arc suhtrscisd from 10. they will
ieaye the last three.
OF THE rwIS-SIA"
g when the ;weive-cyIinder engine
was first brought out the manufacture
;sIs very happily chr!Stened it TIE
-lNtn-SiS, 1t is really two six-cy!inder
snEines, connected together AT the hot
ton, Each OF the two engines mas
Us independent; cylinders. pis;ons,
Sslyes, etc. the Two engines being con.
-attached>'to a single crank shaft. and
Ine Two sets OF cylinders being iastcn-
Gnaa 10 common crank case In
man! engines especially arpiane. these
tIEe Inc only parts common TO the two
seD zines. but many are so designed tina,
single cam -shaft is used for bot h. Or
: a,nSslnE!e carbnre'or is used. while IN
sSonerS me water or oil pump is also
~ INC common crank shaft is practj-
sssiiE inc same as the six.cyiindcr
sScond and fifth and the third and
..LleS9Eth crank pin being in line Thus
Inc hrin. order Of the left and the
L .ha a set OF six-cyiinders will ."
,a9Iher loJ. S2i or 1872. cas-
In some engines No right will fire
3nen NO: j ieti then Il. then ) l.. and
ssTa,,on, !on; the common method is /"
aye No. J right or lcf, hre. .hsu Il
4ett, or right, respectively: ) rIr.ht ."
tnen left or right, and so on.
How TO FIND FIRING ORDER
~ VI I"ELNE-CfLINDER ENGINE
70 Ind the firing order OF a twelve
.sH watching the inle; or exhaust
Islves' md the hring order OF ono Sc,
Of VIZ cylinders. Next set 10. LEFT
10 that Tho exhaust valve has just
xoont closed and see if No right or
No right exhaust waive ix open (urS
~ no , right is open. and the firing
l5S624. then The engine iirInp ordsr
NJ! lie ~. IT. 81. 5R, 81. Gl- CIR. 81,
~, ~. III 4, ~: II No. 6 was. open Cthc
MI be ~. GR, IL, 2I FL. M. GIL. @tc.
the Inlet valves he onei, on the
risht., No o. u. hen the M. right
sEouid he taken as the starter the
hriHG order being | l.. 6l-, OK, ~. etc
In the twelvc-cyiindcr engine The
iTelve cylinders Will all fire, one after
the other, while one cylinder is passing
There being SEQ degrees in 4 cycle. rr
revoiut!on, the twelve cylinders will
hEein go degrees. and il the impulses
they WI! have come every 100 divided
~ - degrees. or every 60 degrees
THIS means that The cylinders will
haHe 20 be set ~ an angle o. co de-
GTccs TO one another.
7r"'Sone OF YOU may have read OF a Ger
tain. twelve-cylinde,, having the cvl-
tAser SET q 10 degree anSll. In this
case mead room and wind resistance
was Il big factor. and the cylinders
were set at the smaller angle TO gain
All advantage in this respect, II being
doaS Al the possible cost of smoothNess
ofrunninr. Many designers claim that
oven In TINS cas- the advantage gained
Nas not WORTH s!ia vibs:ation which APP
& Rafenty resuped~
- = good name FOR the V type of eight
I eyiinGer engine: as used in the auto
twin SIX. is really two engines having
asvornmon crank shaft and crank case
Other parts, such az the camshaft. OF!
also made TO act for both engines