Hudson 63 1936, Руководство по механическим процедурам

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The delivery or upward stroke is obtained by spring
pressure. Three different pumps are used on various models,
however the principle of operation is the same.
Operation
The fuel pump used on all 1934, 35 and 36 Hudson and
Terraplane models shown in Figure 445 is the series "R"
A.C. pump, and will be referred to in describing the princi-
ple of operation.
The rotation of the camshaft eccentric actuates arm A,
which pulls lever C and diaphragm D downward against the
pressure of spring E creating a vacuum in pump chamber F.
During the suction stroke the discharge valve K is held
down against its seat while the inlet valve J is pulled down
from its seat by the vacuum.
The vacuum created causes fuel to flow from the supply
tank, through inlet G, up through screen I and down through
the inlet valve J into the pump chamber F.
As the diaphragm raises due to the pressure of spring E,
the inlet valve raises to its seat while the outlet valve K is
forced upward and the fuel flows through the outlet L to the
carburetor.
When the carburetor bowl is filled, the float in the
carburetor will shut off the needle valve, thus creating a
pressure in the pump chamber F. This pressure will hold
diaphragm D down against the pressure of spring E where it
will remain inoperative until the carburetor requires more
fuel and the needle valve is opened.
It should be noted that the arm A is hinged to lever C so
that lever C can be moved down but cannot be raised by
lever A. Spring M simply causes the arm A to follow the
cam which it does without moving lever C unless lever C is
pulled upward by the diaphragm spring. The pump, there-
fore, delivers fuel
fore, delivers fuel under the pressure of the spring E and only
as required by the carburetor to maintain the proper level in
the float chamber.
Figure 446 shows the Series AK AC fuel pump which is
standard on all 1937 Hudson and Terraplane models. Its
operation can be followed from the above description.
Figure 447 shows the Series AB AC combination fuel and
vacuum booster pump used as optional equipment on all
1937 Hudson and Terraplane models. The fuel (upper) sec-
tion functions similarly to the other pumps.
OPERATION OF VACUUM SECTION
The rotation of camshaft eccentric (A) actuates rocker arm
(B) pivoted at (C) which pushes link (0 ) and in turn dia-
phragm assembly (P) downward expelling the air in chamber
(Q) through exhaust valve (R) and out opening (S) to the
intake manifold. On the return stroke of rocker arm (B)
spring (T moves the diaphragm (P) upward, creating a suc-
tion in chamber (Q) opening intake valve and drawing air
through the inlet passage (W) from the windshield wiper.
When the windshield wiper is not being used, the manifold
vacuum holds diaphragm (P downward against spring pres-
sure (T) so that the diaphragm does not make a complete
stroke for
SECTION 4
Page 24
MECHANICAL PROCEDURE MANUAL
Figure 446—Fuel Pump (1937)
Figure 447—Fuel and Vacuum Pump (1937)