Cooling; Lubrication; Air Induction; Discharge Line Temperature - BENDIX TU-FLO 750 COMPRESSOR Manual

DISCHARGE LINE TEMPERATURE

When the temperature of the compressed air that enters
the air dryer is within the normal range, the air dryer can
remove most of the charging system oil. If the temperature
of the compressed air is above the normal range, oil as oil-
vapor is able to pass through the air dryer and into the air
system. Larger diameter discharge lines and/or longer dis-
charge line lengths can help reduce the temperature.
The air dryer contains a filter that collects oil droplets, and a
desiccant bed that removes almost all of the remaining wa-
ter vapor. The compressed air is then passed to the air brake
service (supply) reservoir. The oil droplets and the water
collected are automatically purged when the governor
reaches its "cut-out" setting.
For vehicles with accessories that are sensitive to small
amounts of oil, we recommend installation of a Bendix
PuraGuard ® QC ™ oil coalescing filter, designed to minimize
the amount of oil present.

LUBRICATION

The vehicle's engine provides a continuous supply of oil to
the compressor. Oil is routed from the engine to the com-
pressor oil inlet. An oil passage in the compressor crankshaft
allows oil to lubricate the connecting rod crankshaft bear-
ings. Connecting rod wrist pin bushings and crankshaft ball
bearings are spray lubricated. An oil return line connected
from the compressor drain outlet to the vehicle engine crank-
case allows for oil return. On flange mounted models, the oil
drains back directly to the engine through the mounting
flange.
FIGURE 7 - LUBRICATION (BASE MOUNT MODEL SHOWN)
®
OIL
INLET
OIL
OUTLET

COOLING

Air flowing through the engine compartment from the action
of the engine's fan and the movement of the vehicle assists
in cooling the compressor. Coolant flowing from the engine's
cooling system through connecting lines enters the head
and passes through internal passages in the cylinder head
and is returned to the engine. Proper cooling is important in
maintaining discharge air temperatures below the maximum
recommended 400 degrees Fahrenheit.
Figure 8 illustrates the various approved coolant flow con-
nections. See the tabulated technical data in the back of
this manual for specific requirements.
WATER
IN
WATER
OUT
FIGURE 8 - COOLING

AIR INDUCTION

There are three methods of providing clean air to the Tu-Flo
750 compressor:
1. Naturally aspirated Local Air Strainer - Compressor
utilizes its own attached air strainer (polyurethane sponge
or pleated paper dry element).
2. Naturally aspirated Engine Air Cleaner - Compressor
inlet is connected to the engine air cleaner or the vacuum
side (engine air cleaner) of the supercharger or
turbocharger.
3. Pressurized induction - Compressor inlet is connected
to the pressure side of the supercharger or turbocharger.
See the tabulated technical data in the back of this manual
for specific requirements for numbers 2 and 3 above.
WATER
OUT
O R
(1 PORT
ONLY)
WATER OUT
WATER
IN
O R
(1 PORT
ONLY)
WATER
IN
®
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