The sun. [volume] (New York [N.Y.]) 1916-1920, 1918-08-18
FUSSING CAUSES
ENGINE TROUBLES
Advice on What and What Not
to Do to Help Keep Motor
in Condition.
ny II. CLIFFORD BRoKAw.

~ Y. Il.
mobile school
Don't grind your vaives--not unless
necessary. Don't be forever fussins
around the motors nostrils any more
than you would about your own. Don't
imagine that every little trouble has its
origin In lsaky valves. II may be. but
you should be sure about 1t before spend
Ing an hour or two that way.
There Is certain class Of driver
which. whenever the engine does not
perform UP to standard. adjusts the
oarbureter. Another class Mes a dollars
worth Of metal from the interrvpter
points. SIN another always wants to
grind valves. There Is nothing which Is
q cureall for engine mnladies.
I havo \ friend who, after working
over his balky motor for an hour,
finally took the pencil out OF the mag
neto and wiped of the grease that had
collected on II. The engine then started
without difficulty. He now performs this
operation to cure everything from boil
ing radiator 10 n nat tire. To date
have been unable TO convince him that
clean the pencil" will not make the
engine run u there 10 no gasoiene In the
tank.
The number OF times valves need to be
ground varies on different cars-varies
widely. But onco year Is more than
enough for the inlet valve. This valve
remains closed when tho combustion
takes place in the cylinder and during
the exhaust, and when Il 10 open nothing
but fresh gas passes through II. There
fore It retains q good seat long and It
Ia a mistake TO grind In the inlet valve
every time the exhaust valve lie doctored.
Certainly so on the ides that IL Is going
to give trouble sooner or later and 1t Is
well to forestall trouble. That IN fall
lacious reasoning.
II the cylinder mishres one Of tho
first things to do 10 TO test the COM
preston with the starting crank to de-
termine II lack OF compression might
be the cause Of the trouble. II the
compression is poor the exhaust valve
usually may be suspected. To deter
mine this fault II 10 necessary to re-
move the valve from the engine. eX-
anime tho SCAT, and II there are par
ticles OF carbon or rough places found
II is time to act. Pieces of carbon may
be scrarNd Of with knife. and this
alone oft iii remedy the difficulty.
However. to make sure OF the seat
Il is well to use some very fine grind
ing compound or -four emery mixed
with oil. and just touch up the seat un-
I'll II shows a continuous gray ring on
both valve and seat. To grind further
Is useless and harmful. Coarse grind
ing compound or too much grinding or
improper grinding will cut rings in the
valve and destroy the seat.
have seen cases where valves have
been ground 20 deep in the casting that
the seat was at the bottom Of well"
and when the valve was pushed open
there was very little space for the pass
age Of exhaust gases. little more
grinding would have worn through the
casting. leaving no seat at all.
When the valves have deep grooves
ground in them they must be swung In
a lathe and faced of or new ones pro-
cured. To prevent this condition use
very fne grinding compound. although
Il may be a little slower than coarse.
Rotate the valve back and forth on Its
seat, using little or no pressure. Every
few twists the valve should be lifted
free Of the seat and given about one
quhrter turn.
II the valve sets in the cylinder care
should be taken to plug up all openings
leading to the cylinder so that no grind
ing compound may work inside. and
care should be taken to wipe all OF the
compound out when the grinding is COM
pIeted. Otherwise It will keep on grind
ing and wear out the cylinder walls.
Sometimes the valves are located
under the head of the cylinder block
and Il is necessary to remove the top.
In other cases they are overhead In re-
movable cages. More usually the valve
is under a cap on the side OF the cylin-
der. 90 that the individual valve may be
removed as desired.
1t IL we'll to check UP the push rod
clearance before and after valve grind
ing: before, because there may be net
enough clearance TO allow the valve TO
seat. thus causing the leak which APP
pears to make grinding necessary after
ward because there may be slight
lowering OF the valve. making adjust
ment necessary. However. II the fore
going instructions are followed there
will not be enough grinding to call for
an adjustment
Before grinding make sure that the
valve needs It and do not grind any
more than. is necessary. After you have
ground enough to give a tight seat all
further effort expendee Is waste. More,
1t Ia harmful to the ea~enc.
The conclusion Ia therefore grind
your valves as often as but not more
often than they need IT. but do not
grind them on general principles or
longer than to make a perfect seat.
Adjust valves carefully and test the
adjustment when a leak Is suspected.
These rules will conserve labor and
gas and prevent grinding the valve seat
through into the cylinder or valve
chamber.