20
BELT ADJUSTMENT
CHECKING BELT TENSION. Check belt tension
should be occasionally, especially if looseness
is suspected. New belts must also be properly
tensioned upon installation.
TENSIONING BELTS
Belt tensioning can be achieved by loosening
the motor anchor screws, pushing the motor
away from the pump, and retightening the
motor anchor screws. Some units are equipped
with a belt tensioning bolt that, when turned,
pulls the motor away from the pump.
Otherwise, the motor can be easily moved by
placing a prying tool beneath it. A commer-
cially available spreader or other belt tension-
ing device can also be helpful.
Follow the procedures outlined below to cor-
rectly set and measure tension.
1. Measure the span length (t) of the drive.
2. Determine the amount of deflection (in
inches) required to measure deflection force
(in pounds) by multiplying the span length (t)
by 1/64. For example, a 32” span length multi-
plied by 1/64 equals 1/2” of deflection required
to measure deflection force.
3. Lay a straight edge across the top outer sur-
face of the belt drive from pulley to sheave.
4. At the center of the span, perpendicular to
the belt, apply pressure to the outer surface of
the belt with a tension gauge. Force the belt
to the predetermined deflection calculated in
step 2.
Ensure the pulley and sheave are properly
aligned and the motor anchor screws are ad-
equately retightened prior to restarting the
compressor.
CAUTION: Improper pulley/sheave align-
ment and belt tension can result in motor over-
load, excessive vibration, and premature belt
and/or bearing failure.
TANK INSPECTION
The life of an air receiver tank is dependent
upon several factors including, but not limited
to, operating conditions, ambient environ-
ments, and the level of maintenance. The exact
effect of these factors on tank life is difficult
to predict; therefore, URREA recommends that
you schedule a certified tank inspection within
the first five years of compressor service. To ar-
range a tank inspection, contact your closest
service center.
If the tank has not been inspected within the
first 10 years of compressor service, the re-
ceiver must be taken out of service until it has
passed inspection. Tanks that fail to meet re-
quirements must be replaced.
WARNING: Failure to replace a rusted air
receiver tank could result in air receiver tank
rupture or explosion, which could cause sub-
stantial property damage, severe personal
injury, or death. Never modify or repair tank.
Obtain replacement from service center.
TROUBLE SHOOTING:
AIR COMPRESSOR
ABNORMAL PISTON, RING OR CYLINDER
WEAR
Lubricant viscosity too low. Drain existing lu-
bricant and refill with proper lubricant.
Lubricant level too low. Add lubricant to
crankcase to proper level.
Detergent type lubricant being used. Drain ex-
isting lubricant and refill with proper lubricant.
Cylinder(s) or piston(s) scratched, worn or
scored. Repair or replace as required.
Extremely dusty atmosphere. Install remote air
inlet piping and route to source of cleaner air.
Install more effective filtration.
Worn cylinder finish. De glaze cylinder with
180 grit flex-hone.
AIR DELIVERY DROPS OFF
Clogged or dirty inlet and/or discharge line fil-
ter. Clean or replace.
Lubricant viscosity too high. Drain existing lu-
bricant and refill with proper lubricant.
Compressor valves leaky, broken, carbonized
or loose. Inspect valves. Clean or replace as re-
quired. Install Valve/Gasket Step. Saver Kit.
Piston rings damaged or worn (broken, rough
or scratched). Excessive end gap or side clear-
ance. Install Ring/Gasket Step Saver Kit.
Piston rings not seated, are stuck in grooves
or end gaps not staggered. Adjust piston rings.
Cylinder(s) or piston(s) scratched, worn or
scored. Repair or replace as required.
Defective safety/relief valve. Replace.
