Could somebody load this into MS Word and export it as a pdf
for me. Open Office has problems with it.
-- 

Paul:
Not edumacated in the ways of computers so I dont know how to create a PDF
doc.
here is the text from the word pad you sent. the pictures are the same as
you just sent through. before.
hope this helps:
michael silvius

INTRODUCTION

The gasoline engine industry's universal acceptance of Tillotson's original
diaphragm carburetor has resulted in the development, by Tillotson
engineers, of the "HL" Series carburetor.

Designed with a minimum of parts, this lightweight, compact carburetor
includes an integral fuel pump and filter in one small unit. The all
position mounting feature allows a wide range of possible applications.

Information contained in the following pages is presented as an aid to
understanding construction, operation and servicing of the "HL" series
carburetor.

CONSTRUCTION DATA

The "HL" series carburetor is a lightweight, aluminum die cast carburetor
composed of four basic parts: metering body, main diaphragm cover plate,
fuel pump body and strainer cover. The diaphragm carburetor incorporates
many of the same type components found in float type carburetor: choke,
throttle, idle and main mixture adjustment screws, idle speed screw and
inlet needle and seat.

Two styles of main and idle adjustment screws are available: "O" ring type
and spring loaded packing type. Both types are designed to perform the dual
purpose of sealing the metering chamber and providing adjustment screw
friction.

A special insert, housed in a brass cage, forms a seat for the inlet needle.
An inlet tension spring exerts a pre-determined force on the inlet control
lever, which holds the needle on its seat.

A metering diaphragm is subjected to engine suction on the metering chamber
side and atmospheric pressure on the vented side. Atmospheric pressure on
the vented side pushes the diaphragm toward the inlet control lever, opening
the inlet needle to allow fuel to enter the metering chamber, from which it
is then delivered into the mixing passages.

The vented side of the metering diaphragm may be vented either directly to
the atmosphere, or in the case of the balanced carburetor, may be balanced
(internally vented) to the choke bore. The balanced type can be recognised
by a brass tube in the choke bore which is connected internally to the
vented side of the diaphragm. The purpose of internal balance is to offset
the enriching or choking effect of a partially dirty air cleaner.

Some carburetor metering systems include a ball check type main nozzle.
These can be identified by the brass cage located in the venturi choke band
of the body casting. The ball check valve allows fuel to flow into the
mixing passage and prevents air from flowing into the metering chamber.

The movement of the pump diaphragm draws fuel into the fuel chamber and a
reverse movement of the diaphragm forces fuel out of the fuel chamber
through the inlet needle and seat into the metering chamber. Movement is
caused by pulsation from the engine, acting on the diaphragm.

A plastic turret inlet connection is the cover to the fuel strainer section
of the carburetor and can be rotated 360 degrees for any required fuel
connection location. The strainer consists of a fine mesh screen to insure
clean fuel supply to the metering section of the carburetor.






ADJUSTMENT INSTRUCTIONS

To properly adjust carburetor for best performance the engine must be
thoroughly warm.

INITIAL ADJUSTMENTS:

To start a cold engine, first carefully close, by turning clockwise, both
idle and main adjustment screws. Open main adjustment screw counter
clockwise approximately one an one quarter (1¼) turns. Open idle adjustment
screw three quarters (¾) turn. Back idle speed regulating screw off its
contact with throttle stop lever, then turn it inward about one (1) full
turn so as to slightly open throttle shutter.

Open fuel line shut off valve, close choke shutter, partly open throttle
shutter and pull starting cord. When engine fires, open choke shutter
slightly and idle the engine. Do not race engine. Then as engine warms, open
choke shutter. To start a warm engine it should only be necessary to pull
starting cord, if the carburetor is properly adjusted.

FINAL ADJUSTMENTS:

Completely close throttle shutter and readjust idle speed regulating screw
so engine idle speed is approximately 1200 RPM for lawn mowers - 2000 to
2500 RPM for chain saws - then slowly readjust idle adjustment screw to
obtain smooth and even engine performance. Poor acceleration may result from
setting the idle mixture too lean.

Starting an engine with the "HL" Carburetor involves the same methods that
are used in a conventional float feed carburetor. However, since a diaphragm
carburetor does not have the advantage of a great reservoir of fuel upon
which to operate, the technique changes somewhat.

When starting a cold engine, place the choke shutter in the closed position
and throttle shutter in a cracked or open position. Several pulls on the
starter may be needed to raise the fuel pressure to the required amount. As
the engine is pulled through with the choke in closed position, engine
suction will be transmitted to the diaphragm fuel chamber through both
primary and secondary idle discharge parts as well as the main fuel
discharge part, creating a low pressure area on the fuel side of the main
diaphragm. Atmospheric air pressure on the opposite side will force the main
diaphragm upward causing the diaphragm button to depress the inlet control
lever, overcoming inlet tension spring pressure, permitting fuel to enter
through the inlet seat, by forcing inlet needle off its seat contact, then
into the fuel chamber side of main diaphragm, up through the idle and main
fuel supply orifices and channels, and out the discharge parts to the
engine.

In starting an engine that has been idle and not running for more than an
hour, it will be necessary to operate and manoeuvre the choking mechanism
for approximately three (3) to ten (10) seconds depending on how cold the
engine has become. The length of time spent warming the engine is only
necessary to the extent that the engine can be made to idle, accelerate and
run satisfactorily under wide open throttle conditions.

IDLING OPERATION

When engine is idling, throttle shutter is in a partially cracked position.
Engine suction is transmitted through the primary idle fuel discharge port
to the fuel chamber side of main diaphragm via the idle fuel supply channel.
Again, the main diaphragm is forced upward by atmospheric pressure,
depressing the inlet control lever overcoming inlet tension spring pressure
and permitting fuel to enter through inlet seat, by forcing inlet needle off
its seat contact, and filling the fuel chamber side of main diaphragm. The
fuel is then drawn up through idle fuel adjustment orifice and delivered to
the engine through primary idle discharge port.

INTERMEDIATE OPERATION

Fuel is delivered into and through the carburetor in the same manner as when
the engine is idling. However, as the throttle opens and engine speed
increases, more fuel is demanded from the carburetor and supplied to the
engine by valving in the secondary idle discharge port located immediately
behind the throttle shutter.

As the throttle shutter continues to open and engine speed increases, the
velocity of air through the venturi creates a low-pressure area at the
venturi throat and diminishes the suction on engine side of the throttle
shutter. When the pressure at the venturi throat is less than existing
within main diaphragm fuel chamber, fuel is drawn up through main fuel
adjustment orifice and out main fuel discharge port into air stream entering
engine intake.

HIGH SPEED OPERATION

As the throttle shutter progressively opens from intermediate position to
full open position, the air velocity through the venturi increases and fuel
is metered up through main fuel adjustment orifice and main fuel discharge
port in accordance with the power requirements of the engine. The action of
the main diaphragm is the same as previously described with suction required
to operate the diaphragm being transmitted through the main fuel discharge
port.




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