The Idaho Republican. [volume] (Blackfoot, Idaho) 1904-1932, 1920-08-11


mote Efficiency-Parts Are Carefully
inspected and Tested In Each Sec
ton Before Motor Gets Final o. X.
When an airplane motor stops some
thing always happensif the motor d
In Q plane flying at any altitude. Many
a witty story has been told by pilots
and ground men In reply to the ques.
ton: "What happens II the motor
stops?"
To follow motor through the nu-
mer0us branches Of the aviation re.
pair depot at Montgomery. Ala. and
attempt to grasp what Is done to 1t In
an actual overhaul is q very interest.
ing process.
The overhaul of an airplane motor
Is described as follows. in statement
authorized by Maj. Gen. Charles T.
Mencher. director of the air service,
himself an expert mechanic:
overhauling a Motor.
"Upon it's arrival on the field the
motor is checked and is Immediately
given work order to guide it on it's
way, and make possible careful rec
ord of its repair and cost. 1t is first
taken to the dismantling room, care
fully taken to pieces and transferred
to the wash rack and washed with
kerosene and gasoline. All carbon is
removed and the pistons are carefully
polished to remove all roughness, that
carbon might not adhere so readily.
From the waShrack it is transferred
to the inspection room, where it Is
given most thorough inspection.
Parts which are worn or damaged to
such an extent that they cannot be re-
placed are Immediately salvaged.
Parts that are repairable are trans
ferred where the necessary repairs are
made, and returned again to the in
spector. A triplicate list of all parts
repaired and condemned is made, one
following the motor. one going to the
engineer officer, and one Is kept on
record in the inspection room. After
the motor is passed by the inspectors
the stock-chaser checks up by the in
spection report the parts which have
been condemned, and draws from
stock new parts to take their places.
He also draws complete set Of gas
kets for every motor, and tries to de-
ho TO Iu
department as nearly complete as pos
sible.
"The motor now becomes the prop
erty of the motor assembly depart
ment. 1t has gone safely through the
inspectors and all parts are supposed
to be in perfect condition, but the me-
chanic has perfect right to reject
from his motor any part which he finds
faulty. There is friendly rivalry be- !,
tween the two departments, the me-
chanic, as rule, loves to hang some
thing on the inspection department
Thus a double inspection Is developed
In this department the bearings are
reamed and scraped, all bearings test
ed by dial indicator tests for clear
ance, valves ground and tested for
leaks. Cylinder blocks which have
been drawn from stock and valves
which have passed the factory inspec.
tors test after assembly are often
found leaky and do not come up to A,
r. D. test. This test consists Of filling
the intake port hole with gasoline, and
from inside the cylinder around the
seat of the valve forcing a 60pound
air pressure. A valve which is, after
testing by gasoline seepage, to all ap-
)earances O. K, will frequently fail
with this air test. After the different
parts are assembled and the motor is
ready for timing. the ignition parts are
lrawn from that department and in
stalled.
Ready for Test.
"The motor is now ready for test
md again becomes the property of
he inspection and test department
This is where they try to hang the
,repe on the motor repair. If the
motor is rejected a report is made by
he test block section, giving reason
or rejection and suggesting the rem.
.dy if possible. A report is made by
he chief of motor repair of what was
ound wrong, and the correction made
'The reports go to the engineer Of.
Ger, who then does the heavy growl-
ng. After second and successful
lock test the motor is tagged o. X =
he tag showing Il. P. NJ, running :
lme, oil pressure and the kind of pro- ,
eller used. Here again it becomes the
roperty of the engine repair. If the
ngine is to be placed at once in a
lane it passes to the final assembly, q
ut If it's destination is unknown the a
ltake and exhaust ports are closed, s
ylinders filled with oil, the entire h
Otor sprayed with protective coat n
lg of cosmoline applied rapidly and h
with an ingenious air gun, h
nd is then ready for shipment, or for n
orage, leaving the aviation repair
epOt In either case a thoroughly re- n
uilt, inspected, tested and, in the O
ase of a rotary, properly russed
otor." +,