The Oskaloosa herald., 1916-02-24

Can you give me the advantages
and disadvantages of cylinders cas-
separately, in pairs and in bloek7
The use of separately cast cylinders
in a multicylinder engine increases the
overall length of the motor and calls
for long crank shaft with more bear
8 ing supports than a pair or block cast
motor of the same number of cylin-
dcrs. This type of motor makes mani
/ fold connections more complicated than
in the other types. and the weight is
greater for a given size because of
lack of cOmpactness. Because of the
complications in manifolding there is
greater chance of leakage in the water
connections and inlet manifold sys-
TEN. A motor with cylinders separat-
ed usually is not as clean in appear
anCe as an engine with cylinders cast
otherwise. The main advantage of tho
singly cast motor is that, should any
trouble occur with one cylinder, that
one only need be removed This de-
sign allows of copper water jackets
being used, which are considered by
many better suited for cooling jacket
material than cast iron. Taking a four
cylinder separately cast motor usually
five bearings are used for crank shaft
support. This makes a rigid construc-
ton for the shaft and tends to prevent
bearing injury. A great advantage in
manufacture is that should a defect
occur in the casting it may be junked
with practically little loss.
The block motor which has made
such rapid strides in the past few
years has its main disadvantage in
manufacture and repair work. Should
casting be found defective the entire
block must be junked with Il conse-
quent loss of money and time. From
an owners point of view a disadvan- |
tage presents itself when repair time |
comes around. Should the interior of |
any one cylinder require attention the |
entire block must be removed, except, |
OF course. where detachable cylinder |
head is used, and then only the head |
requires removal. The detachable head |
on block motors is coming into use
very rapidly. A block is more difficult |
10 cast than a single cylinder. How
ever. present foundry work has been
so improved that the casting of block
cylinders no longer results in great
waste or the production of many |
blocks with unnoticeable imperfections /
further disadvantage of the block |
casting is that should the jacket wa
Ter freeze and cause the metal to crack
the entire block may have to be scrap.
ed unless, of course, an effective weld
IAN be made
A block cast motor is more rigid than
any other, the manifOlding is simple,
and in most cases the manifOlds may
be cast with the block. Unity may be
carried very far in this design, and
many are casting the upper portion Of
he crank case with the block. This
-ype is quieter through life than a sep
'ately cast motor because of the brac-
ng effect Of the cylinders. The crank
shaft of a four cylinder block motor
need not have more than three brac-
ngs, the greater number Of small mo-
ors using two. The block motor has a
shorter overall length than any other
ype. hence shorter shafting and less
weight. II
The advantages and disadvantages of
'air cast motors become obvious from
he answers concerning single and
'lock motors. You must not, however,
believe that every singly cast motor
nd every block motor has the qualities
previously mentioned. 1t is possible
or certain design of block motor to
re more complicated. more costly and
ess clean than one with separate CYL
nders. There are many things to con-
tder, such as valve location and mani.
old design.