BREAKS AIR
TRUCK SERVICE MANUAL
Install inlet valves and inlet valve springs in
cylinder block. Place new cylinder head gasket on block.
TESTING COMPRESSOR
Carefully align inlet valve springs with inlet valve guides
in cylinder head and secure head to block by tightening
A compressor efficiency or buildup test can be run
cylinder head nuts evenly.
which is not too difficult. Before the test the crankcase of
a self lubricated type compressor should be properly
Assembling and Installing Air Strainer
filled with lubricating oil.
An engine lubricated
compressor must be connected to an oil supply line of at
If compressor assembly includes an air strainer,
least 15 pounds pressure during the test and an oil
assemble air strainer, Fig. 13.
return line must be installed to keep the crankcase
Using a new gasket, position and install strainer on
drained. The compressor (when tested) should be
cylinder block.
tested without a strainer.
To the discharge port of the compressor connect a
reservoir or reservoirs whose volume plus the volume of
the connecting line equals 1300 cubic inches. Run the
compressor between 1700 and 1750 RPM. Elapsed
time that the compressor takes to build up from 0 to 100
psi depends on the type compressor as follows:
Build-Up Time
Type Compressor
0 to 100 PSI
Fig. 13 Exploded View of Air Strainer
Tu Flo 500
30 Seconds Maximum
REINSTALL
During the above test the compressor should be
checked for oil leakage and noisy operation.
Clean oil supply line so that oil will flow freely
through the line.
MAINTENAN CE
Be sure oil return line or passages through
It is good practice to follow a preventive
brackets are clean and unrestricted so that oil can return
maintenance schedule at regular mileage intervals to
to engine. Always use a new mounting gasket and be
extend the service life of the air compressor. These
sure oil hole in gasket and compressor is properly
mileage intervals represent requirements for normal
aligned with oil supply line.
conditions. For severe service or unusual operating
conditions the intervals should be reduced accordingly.
Inspect drive pulley or gear for wear or damage.
They must have a neat fit on crankshaft making sure it
Daily:
properly contacts the shaft and not ride the key. Tighten
nut securely and install cotter pin. Be sure air cleaner is
If the compressor is a self lubricated type, its oil
clean and properly installed. If air intake is connected to
level should be checked at the same time the engine oil
engine air cleaner or supercharger, these connections
level is checked. The oil level should be kept between
must be tight with no leakage.
the bottom of the dip stick threads and the bottom of the
dip stick. The oil should be changed often enough to
Clean or replace any damaged or dirty air or water
keep it nonabrasive and noncorrosive.
lines which may be corroded before connecting them to
the compressor. Use a new discharge fitting gasket.
IMPORTANT: Should it be necessary to drain the
engine cooling system to prevent damage from freezing,
Align compressor drive and adjust to proper belt
water-cooled compressors must be drained, as both
tension. Tighten mounting bolts securely and evenly.
cylinder block and cylinder head are water cooled.
Use drain cock or remove head and/or block pipe plugs.
After compressor is installed, operate it and check
for air, oil or water leaks at connections. Be sure to
check for noisy operation.
134
