Arrow Pneumatics BP-123 THROUGH BP-725 Instructions for use

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BLOWER PURGE DESICCANT AIR DRYER
INSTRUCTION & MAINTENANCE MANUAL
MODEL BP-123 THROUGH BP-725
ARROW PNEUMATICS, INC.
2111 WEST 21ST STREET
BROADVIEW, IL,60155
PHONE # [phone]
FAX # [phone]

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BLOWER PURGE DRYER
INSTRUCTION AND MAINTENANCE MANUAL
IMPORTANT
BEFORE INSTALLING OR OPERATING THE DRYER IT IS RECOMMENDED THAT THIS
MANUAL BE STUDIED AND CLEARLY UNDERSTOOD.
SECTION TOPIC DESCRIPTION
1. SAFETY PRECAUTIONS
2. INTRODUCTION
3. INSTALLATION
4. OPERATION
5. MAINTENANCE & SYSTEM CHECK
6. PREVENTIVE MAINTENANCE
7. TROUBLESHOOTING GUIDE
8. PARTS LIST
9. ELECTRICAL SCHEMATIC
10. FLOW DIAGRAM

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1. SAFETY PRECAUTIONS
WARNING
MAINTENANCE OR OPERATING PROCEDURES AND TECHNIQUES
THAT WILL RESULT IN PERSONAL INJURY OR LOSS OF LIFE IF
NOT CAREFULLY FOLLOWED.
CAUTION
MAINTENANCE OR OPERATING PROCEDURES AND TECHNIQUES
THAT WILL RESULT IN DAMAGE TO EQUIPMENT IF NOT
CAREFULLY FOLLOWED.
NOTE
MAINTENANCE OR OPERATING PROCEDURES AND TECHNIQUES
THAT ARE CONSIDERED IMPORTANT ENOUGH TO EMPHASIZE.
Warnings, Cautions, and Notes used in this manual have the following significance:

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2. INTRODUCTION
HOW DOES A BLOWER PURGE DRYER WORK?
The Blower Purge Dryer is a twin tower drying system. It is also called an “absorbent” or
“desiccant” type dryer. In operation, a regenerative dryer has one tower on-line drying the
compressed air stream while the off-line tower is regenerating itself. This process alternates
automatically and consciously on 4 hour intervals. We call on complete cycle an 8 hour
NEMA cycle.
A.Dryer Air Flow Path—Drying/Regenerating
Wet saturated air enters the inlet of the dryer (top) and is routed down through the desiccant
in the on-line tower (left tower is our example). Like a sponge, the desiccants in this tower
soak up the water and dry the air to –40°F pressure dew point (0.0521 gr/cf). At this dew
point, the air is very dry and is sent downstream to your process.
To regenerate the off-line tower (right tower), this type of dryer is supplied with an integrally
mounted centrifugal-type blower. Air (purge air flow) from the blower is delivered to an ex-
ternal heater, to increase its moisture holding capacity, and then routed through the off-line
tower (right tower). The heater raises the temperature of the blower-supplied purge air to
350°F to 425°F.
This heated purge air stream has low vapor pressure which allows it to efficiently dry out
(regenerate) the wet desiccant in the off-line tower.
As the purge air passes through the desiccant bed of the off-line tower, the hot purge air
picks up moisture, drying out the desiccant. The hot purge air gradually “soaks” up all the
water found in the off-line tower’s desiccant bed. Now “wet”, the purge air is discharged
from the drying system through the purge muffler.

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3. INSTALLATION
Arrow Regenerative Air Dryers are shipped as completely assembly packages, filled with
desiccant ready to install.
Visually check the dryer to make certain that all air lines and electrical connections are
securely fastened and were not damaged in transit. If there is evidence of damage,
immediately enter a claim with the carrier, and notify your Arrow representative.
A. APPLICATION CHECK AND ANALYSIS
To achieve the best dryer performance, you should carefully check that the design and
installation requirements outlined below are satisfied.
1. Operating pressure of your Arrow Dryer can range from 60 min to 150 max PSIG. Check
dryer label and ASME nameplate to verify maximum service pressure. Air available for
your air usage will vary with operating pressure.
2. The dryer should not be installed where compressed air and/or ambient temperature
exceeds 100°F or drops below +50°F. Locate dryer to avoid extremes of heat and cold
from other conditions. Best results occur when dryer is located as close to point of use
as practical. Where applicable, dryer towers should be insulated to reduce heat loss.
Avoid locating dryer outside or where it is exposed to the elements.
B. MOUNTING SPECIFICATIONS AND DRYER LOCATION
1. Refer to Electrical Schematic. Electrical connection must be hard piped with an external
fused disconnect switch with proper overload protection.
2. Frame must be suitably ground.
WARNING
ARROW DRYERS ARE WIRED FOR HIGH VOLTAGE. ONLY QUALIFIED
ELECTRICIANS ARE AUTHORIZED TO SERVICE THIS ELECTRICAL
EQUIPMENT.
3. Generally, locate your dryer downstream from the air receiver. The only exception would
be on applications with a fluctuating demand. Then the dryer should be located
upstream of the receiver to avoid air surges through the dryer’s desiccant beds.
4. Provide adequate space around the dryer for servicing. Bolt dryer skid to foundation,
where possible.

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CAUTION
EXHAST PURGE AIR FROM PURGE VALVE MUST BE PIPED OUT-
SIDE OF BUILDING TO OUTSIDE ATMOSPHERIC AIR.
4. To reduce backpressure in your dryer, exhaust purge air from the purge MUST BE
piped outside to atmospheric air.
5. Disconnect and discard the shipping strap securing the centrifugal blower in place.
C. SUGGESTED PIPING ARRANGEMENT
Wet air inlet is at the dryer’s top 4-way plug valve. Dry outlet air is from the dryer’s bottom 4-
way plug valve. See attached flow diagram.
In situations where air supply is required 24 hours a day (it is undesirable to interrupt the
airflow), a three valve bypass system is recommended to bypass the dryer. Use the fewest
elbows and taper connections necessary to keep pressure drop at a minimum.
D. PREFILTERS / AFTERFILTERS
It is important that a prefilter and an afterfilter be provided in your dryer installation.
Prefilters, located before dryer, protect desiccant beds from contamination by oil, entrained
water, pipe scale, etc., thereby extending dryer desiccant life. Locate prefilters as close to
dryer as possible.
It is recommended that a mechanical separator be installed immediately preceding the
prefilter to remove the bulk liquid oil and entrained water.
CAUTION
LIQUID WATER SHOULD BE REMOVED BEFORE THE AIR ENTERS THE
DRYER. BE SURE SEPARATORS, PREFILTERS AND DRAINS ARE IN GOOD
WORKING ORDER.
After filters, located after the dryer, help eliminate the possibility of desiccant dusting and
carryover into the air system.
Install afterfilters as far downstream as practical to minimize exposure to elevated
compressed air temperatures (160°F to 180°F normally) common at dryer tower switch
over. High temperature filters are recommended to prevent rupture possibility in the event
dryer failure should occur. Consult your Arrow representative for appropriate filter selection
and sizing. Plastic bowl type filters are not recommended.

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4. OPERATION
A.START-UP
After all piping and electrical connections are made, proceed as follows:
1. SLOWLY pressurize the dryer. When the dryer reaches full operating pressure, check
the system for air leaks. Soap test all joints and fittings. To maintain desired dewpoint,
any leaks detected must be fixed, especially those on the outlet side of the dryer.
2. After complete pressurization of system has occurred, fully close throttling valve located
at discharge of blower.
3. Energize electrical circuit by pressing the Power On/Off button located on the front
panel. Check motor rotation.
4. If motor rotation is incorrect, de energize circuit and reverse motor leads. Go back to
Step 3. If correct go on to step 5.
5. Attach high accuracy amp probe or ammeter to single leg of supply power to blower.
6. Open throttle valve until amp draw reads the same as the full load amp as shown on the
motor nameplate. Lock throttling valve into position.
7. The Power On LED will be illuminated when the dryer is in operation. When the electri-
cal circuit has been energized, the control circuit board will start to operate and auto-
matically initiate dryer operation. The timer is factory set, so that no field adjustment is
necessary.
NOTE
AT INITIAL START-UP, CHECK THE DRYER OPERATION FOR ONE OR TWO
CYCLES, ESPECIALLY AT THE TIME OF THE TOWER SHIFT. VERIFY THAT
ALL SYSTEMS ARE OPERATING IN THEIR PROPER ORDER AND
SEQUENCE. IF THE DRYER IS NOT FUNCTIONING PROPERLY, CONTACT
YOU ARROW REPRESENTATIVE.
B. DRYER OPERATION
The dryer is fully automatic in operation and will now operate with a minimum of
maintenance and care. Each sequence of operations is programmed by an automatic timer.
Dryer programs may differ slightly, but all perform similar functions.
Standard dryers operate on an 8 hour NEMA cycle with 4 hours drying and 4 hours
regenerating (3 hours heating and 1 hour cooldown).
WARNING
IF THE DRYER IS DE-ENERGED WHILE DRYING SERVICE AIR THROUGH
THE RIGHT TOWER, IT MUST BE DEPRESSURIZED BEFORE RE-
ENERGIZING THE CIRCUIT BOARD.FAILURE TO DO SO COULD CAUSE
PERSONAL INJURY AND DAMAGE TO DRYER

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The purge valve will now open, depressurizing the tower that had been in drying service for
the previous 4 hours. At this point the heater is energized for the three hour heating period.
The purge air flow begins to carry heat into and through the wet desiccant bed. During the
4th hour of the regeneration cycle, the heater is turned off and the purge air is allowed to
continued flowing through the bed.
The now cool purge air cools the desiccant, carrying the heat out of the regenerating tower.
This cool down period is important in reducing both desiccant thermal shock (pulverization
of desiccant caused by excessive temperature differentials) and the exposure of
downstream equipment and processes to excessive temperatures at dryer tower switch
over.
C.TIMER OPERATION
The circuit board timer supplied will provide complete and reliable control for all dryer func-
tions. The timer is completely factory tested and calibrated. No field adjustments of settings
should be necessary. Refer to voltage sequence page for timer operation.
Upon startup the timer will initiate regeneration of the right tower. At the same time the left
tower will begin drying the process gas stream.
Regeneration begins with blower startup. The blower and heater will now remain in opera-
tion for approximately 3 hours.
After approximately 2 hours, the heater will de energize, allowing the regenerating bed to
cool down. The cool down period will last 50 minutes.
At this point the blower will shutoff and a 10 minute stabilization period will be initiated. After
the 10 minute stabilization period, tower shift will occur and regeneration will be initiated as
described above.
D.HEATER OPERATION
For long and efficient heater element life, Arrow externally mounted heaters are operated at
a low watt density. When supplied with proper purge flow, heaters are rated and sized not to
overheat.
CAUTION
HEAT REACTIVATED DRYERS MUST ALWAYS BE PRESSURIZED WHEN
ENERGIZED. HEATERS CAN OVERHEAT AND PREMATURELY AGE IF
PURGE AIRFLOW IS INTERRUPTED OR DISCONTINUED DURING HEATER
OPERATION.
Prior to tower switch over, a 10 minute time interval is allowed to bring both towers to full
line pressure before switch over (right and left tower switch drying/regenerating functions).
This is accomplished by closing both purge valves, and allowing the purge air flow to bring
the off-line tower up to full line pressure. After the pressure in the regenerated tower
reaches line pressure, the 4-way valves shift. This shift should always occur at full line
pressure to prevent rapid pressurization which would agitate, and cause attrition of the
desiccant bed.

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During dryer operation, you will notethat the heater will cycle on and off during the 3 hour
heating period. The heater supplies enough heat that when combined with purge airflow, it
will fully regenerate (dry out) the wet desiccant bed in the off-line tower. The temperature
setting is factory set at 425 deg F and should be maintained at that position
WARNING
DURING THE REGENERATION CYCLE THE OFF-LINE REGENERATION
TOWER GETS HOT. CARE SHOULD BE TAKEN WHENEVER YOU ARE
WORKING ON OR NEAR THE DRYER.
You will note that the tower temperature gauges (located on the panel) will indicate when
desiccant regeneration is nearing completion.
Near the end of the 4 hour regeneration period, a temperature reading of 250°F to 275°F
normally indicates the desiccant bed has been regenerated.
NOTE
AT THE END OF 3 HOUR HEATING PERIOD OBSERVE TEMPERATURE
GAUGE FOR 30 MINUTES. TEMPERATURE GAUGE READINGS WILL VARY
WITH MOISTURE LOADING OF DESICCANT.
SHOULD MOISTURE CONTENT OF INLET COMPRESSED AIR BE LOW (I.E.
DURING DRY WINTER MONTHS) REGENERATION TEMPERATURES MAY
REACH AS HIGH AS 325ºF.
SHOULD MOISTURE CONTENT OF THE COMPRESSED AIR EXCEED
DRYER’S DESIGN CAPACITY, (OVERLOADING, TOO MUCH SCFM,
ELEVATED INLET TEMPERATURE, LOW PRESSURE) TEMPERATURE
READINGS WILL RANGE BELOW 220ºF. SEE TROUBLESHOOTING GUIDE
SHOULD THESE TEMPERATURES BE OBSERVED.
E.MOISTURE INDICATOR OPERATION
Moisture Indicator is provided to warn operating personnel of dryer malfunction. If dryer is
functioning properly, desiccant in Moisture Indicator will be blue. Should blue color fade or
turn pink, consult Troubleshooting Guide.

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F.OPTIONAL EQUIPMENT (IF APPLICABLE)
1. Dewpoint Demand System (DDS)
A. The function of DDS is to conserve energy by eliminating unnecessary dryer cycling and
heater power consumption.
B. The DDS works by utilizing a moisture sensitive probe to measure the water vapor
content of the outlet air from the drying instantaneously to a change in the moisture
content of air stream. The moisture content of the sample air stream indicates the
wetness of the drying tower’s desiccant bed.
The purpose of the probe and its associated electronics is to first measure the “wetness” of
the air within the desiccant beds and then regenerate the desiccant beds only when the
moisture loading reaches a pre-set maximum dewpoint.
C. Dewpoint Demand System Startup and Operation
1. Put dryer’s auto/manual selector switch in “manual” position.
2. Close DDS sample valve
3. Pressurize the dryer
4. Energize the dryer. Allow dryer cycle for 8 to 16 hours. Observe that both towers have
completed a full regeneration cycle.
5. Allowing the dryer to operate for two complete cycles ensures that the probe will not
be exposed to high humidity and damaging liquid water. This is especially important
when dryer has been stored or sitting idle for several months.
6. After this period, slowly open the DDS sample valve sothat a small flow of air
passes across the probe (approximately 2 to 3 SCFH). This valve should be open at
all times when dryer is in operation.
7. Now turn the auto/manual selector switch to the “auto” position. The DDS
operational light will come on to provide indication that the Dewpoint Demand
System has been activated.
NOTE
IT IS RECOMMENDED THAT THE DRYER BE OPERATED IN THE MANUAL
MODE FOR A PERIOD OF 4 TO 6 MONTHS WHILE DESICCANT AGING
OCCURS.
2. Failure to Shift Alarm (FTSA)
A. The Failure to Shift Alarm monitors tower shifting and energize an alarm light on the
front panel of the control box should the regenerative dryer fail to cycle.
B. Should dryer fail to cycle because of malfunction of a system component (i.e. cylinder,
4-way valve, and solenoid valve) the FTSA light will be energized for 4 hours of each 8
hour cycle. Should FTSA alarm light be observed, refer to “Troubleshooting Guide”.

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NOTE
FAILURE TO SHIFT ALARM LIGHT WILL BE DE-ENERGIZED EACH TIME
DRYER TIMER CYCLES TO POSITION WHERE CYLINDER IS STUCK
(EITHER EXTENDED OR RETRACTED). OBSERVE DRYER OPERATION TO
DETERMINE WHICH SIDE OF CONTROL CIRCUIT IS MALFUNCTIONING.
3. High Humidity Alarm (HHA)
A. The High Humidity Alarm monitors the outlet moisture condition and energizes an alarm
light on the front panel of the control box should the regenerative dryer fail to provide
proper dewpoint performance.
B. Should dryer dewpoint elevate because of malfunction of a system component, overflow
condition, oil contamination, or desiccant attrition, the HHA light will be energized.
Should alarm light be observed, refer to “Troubleshooting Guide”.

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5. MAINTENANCE AND SYSTEM CHECK
A. 4-WAY VALVES
All 4-way valve are shipped from stock assembled and filled with proper valve sealant. The
valves are designed with double O-ring seals creating a self lubricating valve. The valve
must be lubricated every 3 months to keep all seals pliable.
To lubricate the 4-way valve, give the lubricant screw (located ontop of the 4-way valve) one
complete clockwise turn once a week. Re-lubricate valve when lubricant screw threads are
no longer visible.
Use steps provided to lubricate the 4-way plug valve:
1. Remove lubricant screw from plug valve. For larger valves, a lubricant gun is
recommended.
2. Insert sealant and add as much as necessary to fill the port completely.
3. Insert lubricant screw back into plug valve. Turn down lubricant screw until increased
resistance is evident. Sealant will ooze out around the valve stem.
NOTE
IF INCREASED RESISTANCE IS NOT FELT AND THE LUBRICANT SCREW
IS 50% OR MORE THREADED INTO VALVE BODY, REPEAT STEPS 1 -3.
CAUTION
A COMBINATION LUBRICANT/SEALANT WITH A SUITABLE
TEMPERATURE RANG MUST BE USED. REFER TO PARTS LIST FOR
RECOMMENDED TYPE. DO NOT USE GREASE!
WARNING
TO AVOID INJURY, DEPRESSURIZE DRYER BEFORE PERFORMING ANY
SERVICE.
WARNING
IF THE DRYER IS DE-ENERGED WHILE DRYING SERVICE AIR THROUGH
THE RIGHT TOWER, IT MUST BE DEPRESSURIZED BEFORE RE-
ENERGIZING THE CIRCUIT BOARD.FAILURE TO DO SO COULD CAUSE
PERSONAL INJURY AND DAMAGE TO DRYER

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NOTE
SHOULD THE DRYING SYSTEM BE OVERLOADED AND/OR
MALFUNCTIONING, CAUSING HIGH PRESSURE DROP, AFTERFILTERS
WILL PREMATURELY PLUG. THIS PROBLEM CAN BE AVOIDED BY
FREQUENT INSPECTION AND CLEANING OF CARTRIDGES.
C. SOLENOID VALVES
Periodically clean all solenoid valves. If the solenoid valves fails to operate, check the
following:
1. Control Circuit -Check the timer micro-switch to verify that the solenoid is receiving
electric current.
2. Burned out solenoid cell.
3. High/low voltage -Voltage should be plus or minus 10% of nameplate readings.
4. Solenoid valve leaking -Disassemble, clean and repack or replace.
D. TIMER
The control circuit board has no maintenance features. Should the sequencing of towers
fail, check voltage sequence to the appropriate solenoid. See attached voltage sequence
schematic.
WARNING
TO AVOID INJURY, DEPRESSURIZE DRYER BEFORE PERFORMING ANY
SERVICE.
NOTE
VALVES SHOULD BE DISASSEMBLED, CLEANED AND RE-LUBRICATED
ONCE EVERY YEAR AS PART OF A REGULAR MAINTENANCE SCHEDULE.
NOTE
THE EXHAUST PURGE DRYER HAS TWO 4-WAY PLUG VALVES. CHECK
AND LUBRICATE EACH VALVE ON A REGULAR SCHEDULE.
B. PREFILTERS AND AFTERFILTERS
1. Prefilters -The cartridges of the prefilters must be changed as often as required to
prevent contamination of the regenerative dryer’s desiccant bed.
The prefilter MUST BE DRAINED DAILY. To prolong filter cartridge life, it is recom
mended that a mechanical air/moisture separator be placed immediately before the prefiter.
If an automatic drain trap is used, check its operation every 48 hours.
2. Afterfilters -The purpose of the afterfilter is to remove residual desiccant dust.

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E. PILOT OPERATED CYLINDER
Should the air cylinder fail toextend or retract, disconnect the pilot line to check if the
cylinder is receiving pilot pressure.
1. If the cylinder is receiving pressure, disassemble, clean and replace cylinder seals as
required.
2. If the cylinder is not receiving pressure, clean or replace solenoid valve or as required.
F. PILOT OPERATED VALVES
Should the pilot operated valves fail to operate, disconnect the pilot line to check if the valve
is receiving pilot pressure.
1. If the pilot operated valve is receiving pressure, disassemble, clean and replace seals
and diaphragm as required.
2. If the pilot operated valve is not receiving pilot pressure, clean or replace solenoid valve
or as required.

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6. PREVENTATIVE MAINTENANCE
A. DAILY
1. Check and record inlet pressure, temperature and flow. Verify that it is within
specifications.
2. Check tower pressure gauge readings within operating tolerance.
3. Check tower pressure gauges for proper dryer cycling
4. Check that there is no condense discharged from prefilters.
5. Verify that pressure in purging tower is 5 PSIG or less.
6. Verify that prefilters and afterfilters differential pressure is within operating limits.
CAUTION
DO NOT USE CONVENTIONAL GREASE. THE SPECIAL LUBRICANT/
SEALANT REQUIRED FOR THESE VALVES IS RATED FOR BOTH HIGH
TEMPERATURE AND HIGH PRESSURE SERVICES. THE PROPER
LUBRICANT/SEALANT IS REQUIRED TO AVOID LEAKS AND/OR
DESICCANT FOULING CAUSED BY “GREASE” BREAKDOWN AT ELEVATED
TEMPERATURE.
B.MONTHLY
1. Check your operating conditions: inlet flow, inlet pressure, and inlet temperature.
2. Check prefilters and afterfilters.
3. Check dryer cycle and sequence of operations. (i.e. drying, depressurizing,
regenerating, heating, and cooling)
4. Check tower temperature gauges during third and fourth hour of regeneration cycle.
C.EVERY 3 MONTHS
1. Replace prefilter and afterfilter elements.
2. Check pilot air filter element and clean.
3. Lubricated both top and bottom 4-way plug valves.
D.SEMI-ANNUALLY
1. Check outlet dewpoint.
2. Blow down relief valves.

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E.ANNUALLY
1. Check desiccant and replace if necessary.
2. Inspect and clean pilot operated valves and replace packings as required.
3. Inspect and clean pilot operated valves and replace packings as required.
4. Inspect and clean solenoid valves, check valves, purge lines and lubricated plug valves.
5. Test lights and switches, replace as necessary.
6. Test electrical components, replace as necessary.
F.EVERY 3 YEARS
1. Replace desiccant if necessary.

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6. TROUBLESHOOTING GUIDE
PROBLEM PROBABLE CAUSE CORRECTIVE ACTION
Elevated
Dewpoint Insufficient purge rate 1. Check blower operation.
2. Check purge piping for obstruction.
3. Clean purge piping and muffler.
Inlet air/gas pressure below
design condition 1. Check pressure source.
Flow rate higher than design
condition 1. Check flow rate and caused for increased Demand.
Inlet temperature above design
condition. 1. Check aftercooler, clean and service as necessary
Entrained water entering
desiccant bed. 1. Check air/moisture separator and prefilter.
2. Replace dryer desiccant if
necessary.
Desiccant contaminated by oil 1. Install suitable prefilter
2. Replace dryer desiccant.
Excessive
pressure drop
in dryer.
Excessive flow rate. 1. Check flow rate.
2. Locate cause for increased air
demand.
Inlet pressure below design
condition. 1. Check pressure source.
Failure to shift
towers from
drying to
regenerating
service.
Not input power. 1. Check timer micro switch.
Defective solenoid valve. 1. Check solenoid valve.
1. Replace motorDefective timer motor
No pilot air 1. Check pilot air-line for blockage
2. Check pilot air-line valve and see if
it is open
3. Check to see if pilot air-line filter is
clean. Replace element if needed
No lubricant/sealant in 4-way
plug valves. 1. Clean and repack both valves with lubricant/sealant.

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Dryer fails to
pressurize Faulty purge valve 1. Check purge valve and its solenoid valve.
2. Check timer micro-switch.
3. Check that Repressurization circuit
is sending a control signal.
PROBLEM PROBABLE CAUSE CORRECTIVE ACTION
Dryer
depressurizes
too rapidly
Purge valve does not close; dryer
depressurizing through purge
valve.
1. Check purge valve and its solenoid
valve.
2. Check depressurization timer
circuit.
3. Check that depressurization circuit
is sending control signal.
Dryer fails to
purge Purge valve does not open; Purge valve stuck in closed
position.
1. Check timer micro-switch.
2. Check solenoid valve. Repair and
replace if necessary.
3. Check that repressurization circuit
is sending control signal.
Excessive back
pressure in
regenerating
tower (above
5PSIG)
Purge muffler does not pass air. 1. Purge muffler is dirty; replace
Purge muffler passes to much air.
Are is leaking across valve 1. Check top 4-way plug valve. Check lubricant/sealant in both 4-way plug
valves. Relubricate with approved
lubricant/sealant.