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CRACKED DIAPHRAGM
This is an item, which has been entirely eliminated by the use of more than one diaphragm. In the Naught Six
car only one was used. At the present time each water regulator has four. If the diaphragm should crack, the steam
escaping through would force the water supply back from the pumps causing them, of course, to cease supplying the
generator.
INSUFFICIENT THROTTLE OPENING
If the throttle is so set that it cannot be opened far enough, the car, of course, will appear to have an insuffi-
cient amount of power. To get this effect, however, the short lever on the throttle would stand at a right angle to the
frame of the car, and such a condition would easily be detected.
VARYING HEAT--WITH SPEED CONSTANT
If the temperature varies as much as seventy-five degrees above and below four hundred degrees while the
car is running at a practically constant speed, it is probable that this is due to an irregular action of the thermostat.
Should the thermostat spring which seats the needle valve be weak or the packing in the water valve stuffing box be
tight, either of which may prevent the valve closing at the proper time, the generator will receive too much water.
Then it may happen that when the valve does close it is too late. The temperature has begun to fall.
If the element should be slightly bent it may spring sideways while expanding, instead of pushing through
the stuffing box. When the tension is sufficient to start motion through the stuffing box, the valve is suddenly opened
too wide, and too much water will be pumped to the generator before it again closes, causing the temperature to drop.
Sometimes this may happen running at a steady rate of speed and with apparently no cause. Another thing which may
cause the temperature to vary (rising, however) is that the "Boiler checks" being imperfect or having a loose seat,
might allow the water to flow back into the tank. Of course, after this happens there would be a rise in the temperature
owing to the lack of water in the generator. The water must move downward through the coils (when generator is
being refilled) pretty well towards the bottom of the generator before the temperature of the steam changes enough to
affect the thermostat, which although it closes will do so too late to prevent a drop in temperature.
VARYING SPEED
If the temperature drops when the car is speeded up it may be due to one of three causes.
First. If the flow motor fuel stem is not screwed into the piston far enough or is worn, the temperature at a
slow speed is a false one, and upon speeding the car up the natural thermostat temperature is regained. Under this
condition, if the temperature is set for slow speed or with the engine running idle, the chances are that when the car is
driven at any higher speed it will be too low.
Second. If the generator is dirty, a quick call for rapid production of steam will result in drop of temperature.
Should the coils have a thick deposit of oil on their inside surface, the heat will not pass through the walls of the pipes
and the above mentioned deposit as
rapidly as it should. It will probably pass through fast enough to keep up the
temperature of superheated steam if the steam is not being used too fast. But when the demand of steam increases and
the flow becomes very rapid, the heat cannot pass through the walls fast enough to maintain a superheat, and the
steam temperature drops.
Third. Under the average running conditions, the thermostat needle valve remains more or less off the seat;
when the speed of the car is suddenly increased and the flow of the steam increases correspondingly, its temperature
drops a small amount quickly, causing the thermostat valve to close. This in turn will cause the flow motor to feed the
full amount of fuel, which would tend to raise the temperature enough in a short time to cause the thermostat valve to
begin opening again. But if the valve is leaking and the extra amount of water continues to pass through to the
generator, the temperature will continue to drop instead of regaining the balance.
BACK-FIRING
Backfiring is a term used to denote the ignition of the gas as it leaves the vaporizer nozzle instead of above
the burner grate. There is no danger connected with it, although it makes a roaring noise. The proper thing to do is to
close
the gasoline valve and let the car continue to run until the gas already in the vaporizer is burned out. Then turn
