1916 Cadillac - GM Heritage Center

60 ADJUSTMENTS
ADJUSTMENTS «1
LUBRICATION OF TIRE PUMP.
One filling of the pump will provide sufficient lubrication for inflating
four or five tires, providing they are all inflated within one week. If a week
or more elapses between the time the pump is used until it is used again, it
should be lubricated before it is used.
To lubricate the pump proceed as follows:
First run the pump for several seconds with the cap screwed tightly on
the connection to which the hose is attached when inflating tires. This will
force back into the crank case of the pump any oil which may have collected
in the oil separating chamber "B." Then stop the pump, remove the plug
in the lower right hand side of the crankcase of the pump and fill with oil
until it overflows.
Cadillac Rear Axle and Transmission Lubricant is strongly recommended
for this purpose. In its absence, the use of a good quality of steam cylinder
oil is recommended.
NOTE—You should bear in mind that it is just as essential to lubricate
the air pump as the engine, and that the pump will not stand up and give
good service unless it receives proper lubrication.
ADJUSTMENT OF TIRE PUMP.
A safety valve "A" operating at a predetermined pressure, is located at
the lower end of the oil separating chamber "B." To alter the pressure at
which the safety valve operates, loosen the lock nut "C" and with a screw
driver change the adjustment of the screw "D." To increase the pressure
at which the valve operates, screw it in. To decrease the pressure, screw it
out. Be sure to lock the adjustment with the nut "C" after making the
adjustment.
Four and a half inch tires, which are standard on the Cadillac, should
be inflated to seventy-five pounds pressure.
TO TIME THE ENGINE VALVES.
As all valves are timed before the car leaves the factory, these instructions
will be found adequate for such slight adjustments as may possibly, from time
to time, be advisable.
The adjustments of the intake and exhaust valves are made by means of
screws in the cam slides. Turning an adjusting screw to the left (screwing it
out) decreases the clearance between the end of the valve stem and the adjusting
screw in the cam slide. Turning it to the right (screwing it down)
increases the clearance.
IMPORTANT NOTICE—Due to the shape of the cams in Cadillac Eight-
Cylinder engines, it is necessary to have the cams in certain positions to
properly time the valves.
To place a cam in the proper position to time the valve operated by that
cam proceed as follows:
Open the relief cocks on the cylinders and crank the engine by hand until
the valve that you are timing has just seated. Then turn the engine further by
hand in the same direction 1¾ inches on the fly wheel. The cam is then in
the correct position for timing the valve.
When the cam is in the proper position, the clearance between the end of
the valve stem and adjusting screw in the cam slide should be from .003 to
.003 of an inch when the engine is cold.
Each valve should be timed in this manner.
TO GRIND THE VALVES.
The valves in the Cadillac engine are carefully ground when the engine is
assembled and should not soon require further attention.
When it has been determined that a valve requires regrinding, proceed as
follows:—
Unscrew the cap directly over the valve to be ground, and remove the side
plate from the cylinder block.
Remove the locking collar from the lower end of the valve stem. This may
be done after forcing up the washer at the lower end of the spring. Then
remove the valve, being careful to mark it, in case more than one is taken
out at a time, so that it can be replaced as originally assembled.
Next, stuff a piece of cloth into the port between the valve chamber and
the cylinder. This will tend to prevent the grinding material getting into the
cylinder. It is a good plan to wrap soft string around the stem of the valve
near the head. This will tend to prevent the grinding compound getting into
the valve guide.
In the absence of a good prepared grinding compound, make a paste of
powdered glass or flour of emery, mixed with thin oil.
Place the grinding compound on that portion of the valve which bears on
the valve seat. Then replace the valve, and with a screw driver or other
suitable tool, rotate it back and forth about one third revolution, with only a
slight pressure on the tool. Lift the valve occasionally and turn it to a new
position. Continue the grinding operation until the valve and its seat show
perfect bearing.
Then thoroughly wash the valve, the valve chamber and the valve guide
with gasoline. Be very careful to leave none of the grinding compound in any
part of the cylinder, as it will cause serious damage if it works into the
cylinder bore or other parts of the engine; also remove the cloth from the
port and the string from the valve stem.
Replace the valve and rc-time it. (See under To Time the Engine
Valves.) Re-timing is necessary, as the amount of clearance between the
valve and the adjusting screw in the cam block is necessarily reduced during
the grinding operation.