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false pressure, and the pumps may be pumping against a much higher generator pressure than is indicated by the
steam gauge. A Car containing a generator in this condition does not possess very much reserve power.
PRESSURE DROPS QUICKLY WHEN CAR SPEED IS CONSTANT.
This is a very rare occurrence. Should it happen accompanied by a peculiar moaning sound, the chances are
that the checks in the hand pump are allowing the water in the generator to escape back to the water tank. In case this
should happen while running on the road, the proper thing to do is to immediately shut off the fuel and let the pumps
renew the supply in the generator. After this has been done, turn on the fire and conditions will be normal again.
Unless this is done, the lower generator coils would become overheated before the water could be pumped in.
EXCESSIVE PRESSURE AFTER STOPPING A FEW MINUTES.
If the coils are too hot, the reserve heat contained by them will cause the steam pressure to rise gradually
after the flow of steam stops. If the coils have a deposit of carbon on their inside surface, their temperature is greater
on the outside than that of the steam contained within (see Dirty Generator under Excessive Fuel Consumption),
especially if the car has been running at a good speed. After stopping a few minutes, this heat will soak through to the
steam inside, thus raising the pressure.
A SLOW GAS LEAK
A slow gas leak sufficient to keep a simmering fire under the coils will cause the steam pressure to rise
steadily if the throttle is closed. Always close hand valve at seat when stopping.
EXCESSIVE LOSS OF PRESSURE AFTER STANDING A FEW MINUTES
If the running temperature is low there is not much reserve heat in the generator, consequently the pressure
will drop very rapidly after stopping.
HAND PUMP OR BOILER CHECK LEAKING
This is the same condition as is given under number two.
SAFETY VALVE LEAKING OR ANY STEAM LEAK
The volume of the steam in the generator being so small, a leaking safety valve or any leak will cause the
pressure to drop in a short time while standing. All conditions being correct and everything tight, the car should stand
twenty-five minutes to an hour and still contain pressure enough to move itself, the time, of course, depending upon
the temperature of the atmosphere.
FIRE BURNS TOO LONG IN ORDER TO MAKE STEAM PRESSURE REACH BYPASS POINT
If, when starting out with a cold car, the fire is on full and the pressure is not rising, the fire should be shut
off for a moment or two, until the pumps can have a chance to force an additional supply of water into the generator.
After a few moments the fire can be turned on, on condition that the pressure starts to rise immediately. Owing to the
fact that the thermostat controls the temperature by means of its feeding an auxiliary supply of water, it can have no
effect on the lower coils until a certain amount of water has entered the generator. This precaution holds good either
for starting up the car when the engine is running idle, or when the car is pulling out on the street. On the other hand,
if after the car has been running idle and under an additional load, such as climbing a grade, the fire burns steadily
without boosting the steam pressure, the chances are that the generator is dirty. Before coming to any conclusion like
this, however, it should be known that there is a full flow of fuel to the burner. Also that the temperature of the steam
is correct.
SLUGGISH CAR
If the car does not seem to have the proper amount of reserve power, if it does not move out at once when the
throttle is open, the possibilities are that the trouble can be traced to one of the five items mentioned on Chart Two
under this head. For more specific details these may be looked up elsewhere.
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