New-York tribune., 1909-05-02
The Crafts Capabilities are
Measured by Those of
Its Engine.
CHAPTER III.

CHAPTER llI.
However certain a man may be Of the construc-
ton os the hull OF his motor boat II he Is not GER
tain Of the engine which propels it he had better
not venture far In the craft for the strength or
an iron bar is equal only to the strength or It's
weakest part, the capabilities OF motor boat
equal only TO ths capabilities OF its engine IL
there is any one feature Of motor boat construc-
ton upon which purchaser needs Information
above all others 1t is engines. their making their
cement, their strong points and their weak
points. If any purchaser is inclined to doubt this
assertion. few hours adrift. even on the compare
lively quiet surface of inland lake, enforced
through trfing flaw in the working OF his
motor boat engine which little more knowledge
Of the mechanism would have enabled him TO rec
tify in few moments. will probably serve to con-
vince him OF the truth OF this assertion So
keeny DO motor boat men of experience realize the
vital value OF the engine to the all-around ef1-
cheney OF their craft that It has come TO be the
general practice among them when they purchase
new boats, to select their pet make OF engine and
have IT put in hull built to order from special
designs.
One Of the very first things to be learned in re-
searches among gasoene motor boat engines Is
that all such engines depend for their power upon
the explosion OF a compound IN the proper per
centage of air and gasoiene vapor ignited by an
electric spark After examining into the various
| methods OF bringing about this combustion one Is
brought face face with the fact that unless the
compound is mixed in exactly the proper proPor-
tions and the ignition OF the spark occurs at ex-
acfIv the right instant the operation of the engine
he 81 large small, of cylinder more, is
| family Also at the very outset OF his investiga-
| tions the purchaser learns that all gasolene en-
zines stripped Of their various or less useful
sracial attachments. divided into two classes
torcvcIe engines in which there is only one I'M
,Iss at full power for each revolutions OF the
craru shaft and two-cycle engines in which an
| ironuIse occurs at each revolution OF the crank
| sbaf+ Engines of either type usually good
zer1ices BILE machines, but because machinery IS
ohso,utev perfect each has its peculiar short
| comngs
| The dinerent methods by which the fuel supply
| &, 1,-,Jshed through the medium OF carburetors,
| suction or vaporizers constitute study in them
selves and after he has examined into each the
| arrtr. purchaser finds that II he gives IT half
| chance principally by keeping his gasolene free
s 5irt or grit (in clean vessels instead Of in old
,-+ cansl any reliable fuel supply system will do
| ~. pork other duties, such as always testing
| e., rorL,ne device before starting trip, keep
! 80 ~. 1zater Jacket about the cylinder filed with
rTster and the oilcups with oil are forced upon him.
TWO AND FOUR CYCLE ENGINES.
| rrh .rtef point of difference between the two
| -, o,d the four-cycle engine lies in the fact
49, On the former the supply and exhaust valves
| ,ttcb I'm the four-cycie type are usually opened
| and closed by pstons or other mechanical means
| 80 ,rerated by suction set up in an alright case
| =, hitch the main driving crank revolves. thus
! .o,a,,csl,v doing away with two strokes. To
| -. +ba assertion that type Of engine is bet
| - +hor the other Is to revive never falling
! o,,-o. of dispute among motor boat men, Eaoh
.,,a has its advantages and disadvantages IL ls
| 20 o. the tvo-cycle engine that il is lighter in
tio. - "a the power produced that II is steadier
n;as and has fewer parts TO care for, while the
-s.-. of the tour-cycie type point out that
-, . ,here is no possibility of crank chamber eX-
nosions. With their sggraYatng and sometimes dis