Autopulse Fuel Pump
Put the end of the tubing into the coupling elbow, slip the nut
(L) over the ring (0) and tighten it on the threads on the elbow.
The inside walls of the nut so press upon the wedge ring that it
binds upon the tubing, and thus makes an absolutely liquid and
Make connection (E), from the carburetor to the bottom of the vacuum
tank, and connection (U), between the top of the vacuum tank, marked "fuel
line" on cover and the old fuel line.
As the fuel line in different ears varies in size it may be necessary
to procure a coupling nut of a size at one end to fit the Stewart
five-sixteenth-inch connection and at the other end to fit the
. Replacing Gravity Fuel Feed with the Stewart Vacuum Fuel Feed
When the Stewart vacuum system is to be installed on cars having
the gasoline tank under the front seat, or in a compart-ment at
the rear of the car, the most important point to be remembered
is the location of the air vent. The air vent positively roust
be placed at as high a point as is possible under the hood.
Regular instructions on preceding pages cover all the operations
necessary to install the system.
The vacuum tank should be placed at a point where the top of the
tank at the very least is above the level of the top of the gasoline
tank under the seat. It should be placed higher, if possible. The
best location for the tank is on the engine side of the dash. On
some cars it will not be found possible to place the vacuum tank
on the dash, and in such cases the tank can be fastened to the
intake manifold. It will not be difficult to make a bracket for
this purpose. (Manufacturers are Stewart-Warner Speedometer Corpn.,
See page 752 for the Kingston Autovac Gasoline
Fuel Feed System.
See page 112 for the air-pressure system. The Cadillac (page 1283,
Fig. 1) is a typical example of this type.
AUTOPULSE MAGNETIC FUEL PUMP
Purpose: This electric gasoline pump is manufactured by the
Ireland & Matthews
Mfg. Company, Detroit, Mich., under the Lea patents. It was de-signed
with the object of supplying a fuel system that will furnish a
positive supply of gasoline under any condition of grade, hill,
climate, or speed, and to operate independent of any condition
of vacumn in the manifold or air pressure in the supply tank.
The Autopulse is connected directly to the carburetor
suction line, and a wire terminal from the device is installed
on battery side of ignition switch. Thus contact is made as soon
as the ignition switch is turned on. Gasoline is then sucked from
the main supply tank and delivered to the carburetor.
Principles of operation: The metal bellows (3) is expanded by
the magnetic pull, created by armature (10) and magnet (16). This
forms the suction stroke and fuel is drawn through the gasoline
line from the main supply tank, past the suction valve (6) into
The bellows is then closed by the action of the driving spring
(14) and the gasoline forced through the outlet valve (4) into
the carburetor float bowl.
As soon as the carburetor is filled with fuel to the correct heighth,
the carburetor needle valve seats and a hydraulic pressure is built
up, in the Autopulse bellows, which holds the contact points (11)
apart and the pumping action stops until the carburetor float falls
again—due to lack of gasoline in the bowl.
The hydraulic pressure is then broken and the contact points come
together again, making the electrical circuit, and the Auto-pulse
After the ignition switch is once turned on the Autopulse is automatic
in operation, and when turned off, the gasoline supply is cut off —in
case of fire, for instance, from the engine.
Due to the fact that its suction power is so great, it is not necessary
to prime the Autopulse —as it picks up the fuel itself.
In case of accident, it is generally advisable to replace the
unit with a new one. Do not remove brass screw (4).
Only the upper chamber normally contains fuel as indicated by the
arrows in the illustration. Should a leak occur, possibly due to
defective material, the fuel will drain down and onto the breaker
contacts. These will then, in time, become carbonized or greasy
and will cause the operation to become more or less erratic or
even fail. A leak will develop gradually and this warning is given
while it is still so small that it will cause very little inconvenience.
Operation for considerable traveling can be obtained after this
warning is given, by observing the following instructions: First,
sharply rap the top of the pump with a block of wood while the
current is applied. This will usually produce results and may be
all that is required. If this is not sufficient cut off the ignition-switch,
remove the cap screw (13), the magnetic shell
(15) and allow the fuel to dry off somewhat. Clean the contacts
with a file or linen cloth (no fuzz). Replace shell, driving spring
and screw. Remember the unit will not operate without the magnetic
Fig. 10. Cut-away perspective drawing, actual size, of the Autopulse.
(1) outlet to carburetor; (2) inlet of gasoline.
The device is practically sealed against outside leakage and there
is no danger of fire from an inside leak. It is almost impossible
to fire gasoline under the conditions maintained with-in the Autopulse,
and, even if it were possible, there could be no harm, as there
is very little air to support combustion. A screen is provided
to prevent fuzz and coarse particles of metal or dirt from getting
into the valves.
A restriction in the suction pipe will be indicated by the am-meter
deflections. Normally the ammeter deflection cannot be noticed,
but in case of restriction the current builds up, sup-plying more
power to overcome the resistance and for a serious obstruction
the current may build up to three amperes. Under this condition
the deflection of the ammeter needle will be very apparent. Restrictions
may develop in service due to thescreens clogging or the tube may
get pinched through accident.
Access to the strainer or screen is obtained by the removal of
cap screw (8); however, this should not be removed unless the ammeter
indicates a restriction. In case it is removed, the fiber gasket
(9) Hurst be carefully replaced and preferably shellacked. A leak
in this gasket will allow air to enter. If the suction valve (6)
is removed, attention must be given to properly replacing the cork
gasket and the other parts in order. The spring should be placed
within the pronged cap with the small hole up. The boss at the
center of the valve should be placed in the hole with the polished
seat up. The delivery valve (4) should never be removed.
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Autopulse Fuel Pump