1948-1952 Shop Service Manual - - Hudson-Essex-Terraplane Club

FUEL SYSTEM & EXHAUST 4 - 31
AIR CLEANER, DRY
(Oil Wetted Type)
The oil wetted type of air cleaner is used as standard
equipment on all models. In this type cleaner the wire gauze
is oil soaked. As the air passes through it, foreign particles
are removed, permitting only clean air to enter the carburetor.
The air cleaner section should be cleaned at least every
2,000 miles, oftener if local conditions warrant.
This filter can be cleaned by removing the attaching wing
nut and lifting out the unit. Clean off old oil and dirt by
dipping in kerosene and blowing dry. Re-oil by dipping unit
in engine oil (using the same grade as is used in the engine).
Permit excess oil to drain off and reInstall unit in cleaner.
FUEL PUMP
Carter mechanical fuel pump M-729SZ, Figure 103, is used as
standard on all "A" series Hudsons. A combination fuel and
vacuum pump, AC Type AJ, Figure 104, is available as an option.
Operation of the fuel pumps is similar. The pump cam lever (A)
fits under an eccentric on the camshaft. Rotation of the camshaft
forces the cam lever down against the diaphragm spring (B) pressure,
raising the diaphragm (C). Fuel is drawn into the fuel chamber
through the inlet port (D), screen (E), and inlet valve (F).
When the low side of the eccentric is against the cam lever, the
diaphragm spring forces the diaphragm down, expelling fuel
through the outlet valve (G) and outlet port (H) to the carburetor
bowl.
OIL BATH AIR CLEANER
The oil bath air cleaner is available as an option. In this
unit, dirt is precipitated from the air into the oil as the
incoming air strikes the oil in the sump.
The oil bath type air cleaner should be serviced at 2,000
mile intervals, or more, frequently during severe dust conditions,
as follows:
1. Unscrew and remove wing bolt at top of cleaner.
2. Lift out filter element; clean in gasoline and drain.
3. Remove old oil, wash out base, and refill to level indicated
with 50 S.A.E. oil for temperatures above 32° F
and 20 S.A.E. for lower temperatures.
FIGURE 104
Continued pump operation fills the carburetor bowl, and the
float needle valve closes the carburetor inlet. Fuel pressure built up
in the pump fuel chamber opposes the diaphragm spring, resulting
in shorter strokes until the pump stops completely. Normal diaphragm
stroke is about 1/64".
COPYRIGHT 1949 BY CARTER CARBURETOR CORPORATION.
ALL RIGHTS RESERVED.
FIGURE 103
The vacuum section of the combination fuel and vacuum pump
acts as a vacuum booster for the windshield wiper. The same
eccentric and cam lever that operates the fuel pump operates the
vacuum pump. The cam lever forces the