micronAir AU8000 User manual

AU8000
SPRAYER
Operator's Handbook
and
Parts Catalogue
Micron Sprayers Limited
Bromyard Industrial Estate
Bromyard
Herefordshire HR7 4HS
United Kingdom
Tel: [phone]
[phone]
Fax: [phone]
[phone]
E-mail: [email protected] Iss 15W
Web site: www.micron.co.uk 03/20

TABLE OF CONTENTS
1. INTRODUCTION.............................................................................................1
2. SPECIFICATION.............................................................................................1
3. ASSEMBLY.....................................................................................................2
4. OPERATION ...................................................................................................3
5. HEALTH AND SAFETY...................................................................................5
6. CALIBRATION................................................................................................. 6
6.1 Output Rate of Chemical.......................................................................6
6.2 Adjustment of Droplet Size.................................................................. 10
7. MAINTENANCE ............................................................................................12
7.1 Knapsack Mistblower – Routine Maintenance .................................... 12
7.2 Possible Engine Faults and Remedies................................................ 13
7.3 Maintenance of Sprayhead................................................................. 14
8. PARTS LISTS................................................................................................16
8.1 AU8000 Sprayhead.............................................................................16
8.2 AU8000 Atomiser................................................................................18
9. CONVERSION FACTORS ............................................................................20

MICRONAIR AU8000 SPRAYER
1. INTRODUCTION
The AU8000 Sprayer consists of a Micronair AU8000 sprayhead mounted on a knapsack
mistblower.
The sprayhead provides a narrow, easily controlled spectrum of spray droplets to ensure
an even distribution of product with a minimum of wastage. Air from the mistblower rotates
the atomiser and is then directed into the airstream which carries the spray safely away
from the operator and ensures maximum swath width and penetration of foliage.
The AU8000 sprayer is intended for use in agriculture, public health spraying, migratory
pest control (locust, armyworm etc.) and in any other application where a safe, effective,
portable sprayer is required. It can be used with conventional water-based chemicals
(both solutions and solids in suspension) and with specialised ULV formulations. The unit
is supplied with easily interchangeable restrictors for quick and easy calibration of output
rate for all chemicals and application techniques.
Regardless of chemical type or application rate, the AU8000 sprayhead ensures optimum
coverage of the target with a minimum wastage of chemical due to incorrectly sized
droplets or run-off.
The AU8000 sprayhead is also available separately as a conversion kit for use with an
existing mistblower. For satisfactory operation, the air output from the mistblower must be
as shown in the specification below.
2. SPECIFICATION
AU8000 Sprayhead
Length: 30 cm
Diameter: 15 cm
Weight: 1.5 Kg
Air inlet tube dia: 63 mm
Chemical flow rate: 0.07 – 1.20 litres/min
Spray droplet size: Adjustable 40 – 200 microns VMD subject to formulation used
Tank and Blower
Chemical tank capacity: 12 litres max, 10 litres recommended working capacity
Weight (empty): 10.7 Kg (without sprayhead)
Engine: 72.3 cc 4.1 HP (3.0 kW) 2-stroke
Fuel tank capacity: 1.4 litres
Fuel consumption: 1.8 litres/hour at maximum (spraying) throttle setting
Blower output: 23 m3/min
Air velocity: 125 m/sec at outlet

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MICRONAIR AU8000 SPRAYER
3. ASSEMBLY
These instructions apply both to AU8000 sprayheads supplied as part of a complete
sprayer and to sprayheads supplied as conversion kits. The steps with numbers in square
brackets [ ] refer to conversion kits ONLY and should be disregarded when assembling a
sprayer supplied complete. There may be some minor differences when installing
conversion kits on some models of sprayer. Parts are identified by their reference number
in Fig. 5.
[1.] Ensure that the mistblower is empty, clean and in good running order.
[2.] Disconnect the chemical feed hose from any existing on/off valve or flow regulator.
Leave the feed hose connected to the chemical tank.
[3.] Remove the original spray nozzle and outlet, leaving only the flexible air duct and
rigid air tube attached to the blower.
4. Slacken both clamping screws of the handle and valve assembly (13). Slide the
handle over the rigid air tube with the handle angled towards the sprayhead. Position
the handle over the stepped part of the air tube. Leave both clamping screws loose.
5. ONLY if installing a conversion kit, cut the air tube (19) as required to give a
comfortable position for the sprayhead when held by its handle.
6. Insert the end of the rigid air tube (19) into the inlet of the sprayhead so that 40 mm of
tube is inside the casing. Rotate the sprayhead so that the drain hole in the casing is
at the bottom. Secure the sprayhead to the air tube with the pipe clip (20).
7. Put on the knapsack mistblower and hold the sprayhead at the correct angle for the
crop or pest to be sprayed. Rotate the handle to the most convenient position and
tighten the two clamping screws
8. Place a pipe clip (20) over the end of the flexible air duct and tighten the clip to grip
the air tube.
9. Push the feed hose from the chemical tank on to the inlet fitting (17) of the control
valve. Note that this fitting is stepped to accept varying sizes of hose. If necessary,
the hose should be cut to length or replaced if it is too short. Secure the hose with
the pipe clip (12) provided.
10. If using a fixed restrictor tube, select the appropriate flow restrictor tube (8) (see
section 6) and fit this to the outlet of the on/off valve using the cap nut (14). If using
the optional stepped flow restrictor valve, connect the outlet fitting of the control valve
to the inlet of the restrictor valve using the hose provided and connect the inlet tube of
the sprayhead to the outlet of the restrictor valve. Ensure that the filter (16) is in
position.
11. Connect the atomiser feed hose (11) to the outlet of the flow restrictor and secure
with a pipe clip (12).
12. Fill the tank with a non-toxic liquid (e.g. water for conventional application or
kerosene for ULV) and run the sprayer for several minutes (see Operation section 4)
to test for leaks.

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MICRONAIR AU8000 SPRAYER
Fig. 1 – Attachment of AU8000 Sprayhead to Mistblower
4. OPERATION
This section describes the operation of an AU8000 sprayer with the knapsack mistblower
supplied by Micronair. If the sprayhead is used with a different mistblower, some operating
procedures may differ; refer to the mistblower manufacturer's instructions.
1. Make up a mixture of 50 parts regular (NOT high octane) petrol (gasoline) and 1 part
(2%) two-stroke oil. For the first five fills of the fuel tank the oil concentration should
be increased to 25:1 (4%). Standard engine oil should NOT normally be used. If
two-stroke oil is not available, SAE 30 oil may be used for short periods but the
mixing ratio must be 25 parts fuel to 1 part oil (4%). See mistblower instruction book
for full fuel mixing instructions.
2. Close the fuel valve under the fuel tank and pour fuel (as mixed in step 1) into tank.
DO NOT OVERFILL.
3. Ensure that the chemical control valve on the handle is closed with its lever parallel to
the sprayhead.
4. Remove the cap of the chemical tank and check that the flexible air hose inside is
pushed firmly onto the fitting at the bottom and into the filter at the top. Also check
that the cap at the opposite side of the inside of the tank is pushed firmly in place.
5. Pour the required amount of chemical into the tank and replace the cap firmly.
6. Open the fuel valve.

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MICRONAIR AU8000 SPRAYER
Fuel Valve Choke Lever Throttle Lever
Fig. 2 – Engine Controls
7. Move the throttle lever on the handle to the central START position.
8. If the engine is cold, move the choke lever down to the CLOSED position.
9. Ensure that the sprayhead is in a safe place away from foliage or obstructions.
10. Put your left foot on the lower part of the sprayer frame and your left hand on the cap
of the chemical tank to stabilise the machine. Pull gently on the recoil starter cord
until you feel maximum resistance (the engine compression is at its maximum). Pull
the cord rapidly and firmly until the engine starts. DO NOT pull the cord hard against
its end-stop. Should the engine fail to start, do not allow the carburettor to become
flooded with fuel. If the carburettor does become flooded, proceed as follows:
i) Open the choke by moving the lever fully upwards.
ii) Close the throttle.
iii) Pull on the starter cord 10 – 20 times.
iv) Wait several minutes and repeat steps 8 – 10.
11. Allow the engine to idle for 15 – 20 seconds and then slowly move the choke lever
fully upwards to the OPEN position.
12. Allow the engine to run at approximately 50% of its maximum speed for one minute
and then set the throttle lever to the IDLE position so that the engine idles smoothly.
13. Lift the knapsack mistblower onto the operator's back. Note that the operator must
hold the sprayhead and NOT let it drag on the ground. This operation is easiest with
two people. However, the operator can put the knapsack on alone if it is first lifted
onto a waist-high surface.
14. When in the spraying area, set the throttle lever to its MAX position. DO NOT run the
engine for a prolonged time at part throttle.
15. Turn the flow of chemical on and off with the valve on the handle. The lever of this
valve may either be pressed down against its spring for intermittent operation or may
be raised to a locked position for continuous spraying.
16. Only open the chemical valve when the mistblower is running at its correct operating
speed (MAX throttle). Opening the valve when there is no airflow can result in a
build-up of chemical inside the sprayhead and the risk of contamination or plant
damage when the airflow is increased.

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MICRONAIR AU8000 SPRAYER
17. The sprayer must always be directed DOWNWIND of the operator and each pass
through the sprayed area must be UPWIND of previous passes. This ensures that
the operator is always walking through an unsprayed area and cannot be
contaminated by any spray blown back by the wind.
18. The sprayer should be held at a distance of at least 1m (3 ft) from the target
whenever possible. This ensures an even distribution of spray droplets and
minimises the risk of damage to vulnerable crops by high velocity air from the
sprayhead.
19. The rotating gauze of the atomiser should not be allowed to come into contact with
foliage or the operator.
20. When using a ULV drift spraying technique to give a wide swath in open terrain (e.g.
locust or armyworm control), the sprayhead should be held at an angle of about 30
degrees above the horizontal. This allows the wind to carry the spray from the
maximum height to achieve the widest swath.
21. Set the throttle lever to the idle position after closing the chemical valve if the sprayer
is not to be used for more than one or two minutes. However, do not allow the engine
to idle for a prolonged period (see point 16 above).
22. To stop the engine, move the throttle lever to the IDLE position and allow the engine
to idle for one minute before moving the throttle lever fully anti-clockwise to the STOP
position.
23. The entire sprayer, including the AU8000 sprayhead, must be thoroughly cleaned
after use. If a ULV chemical has been used, it must be flushed out with a suitable
solvent such as kerosene. Water is only suitable if a water based formulation has
been used. The outside of the sprayer, the tank, hoses and sprayhead must be
cleaned AFTER flushing the tank hoses and atomiser.
5. HEALTH AND SAFETY
The AU8000 sprayer must be used by a qualified operator in accordance with the
recommendations and statutory requirements for the use of sprayers and the chemical
being sprayed.
These requirements will be set out in the applicable local legislation and in the label of the
chemical.
In the United Kingdom, the precautions and regulations concerning the use of pesticides
and sprayers are defined in the Code of Practice for the Use of Pesticides on Farms and
Holdings (Published by HMSO for the Ministry of Agriculture, Fisheries and Food and the
Health and Safety Commission).
The use of pesticides and sprayers are subject to legislation or codes of practice in most
other countries. It is the responsibility of the user to ensure that these are read,
understood and complied with.
The following recommendations are for guidance only and do not exclude any statutory
requirement:

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MICRONAIR AU8000 SPRAYER
1. Always wear adequate protective clothing, eye protection and respiratory protection
when mixing, transferring or spraying pesticides. The minimum level of protection will
be stated on the chemical label or in the Code of Practice in most countries.
2. Protective clothing, respirators etc must be removed as soon as exposure to
pesticides has ceased. All items must be washed or disposed of safely according to
the manufacturers' recommendations.
3. Ensure that the sprayer is correctly calibrated for the chemical, application technique
and crop or pest being sprayed.
4. Take note of the speed and direction of the wind. Ensure that spray droplets do not
drift on adjacent crops, another person's land or an inhabited area. Always spray
downwind to avoid operator contamination. Never walk through a sprayed area.
5. All traces of chemical must be washed from the operator's skin immediately after
spraying and before eating, drinking or smoking.
6. Remove all traces of chemical from the tank, pipework and sprayhead as well as from
external surfaces of the sprayer.
7. All residues of chemical from the sprayer, pesticide containers or mixing vessels etc
must be disposed of safely by an approved means. Do not contaminate an off-target
area or allow pesticides to reach streams, wells or groundwater.
8. Dispose of empty chemical containers safely by an approved means. Do not keep
containers for re-use for other purposes.
6. CALIBRATION
As with any mistblower, an AU8000 sprayer must be calibrated before use. This involves
setting the correct output rate of chemical and adjusting the sprayhead to produce the
appropriate droplet size for the chemical and application technique being used.
The following sections describe the calibration of a standard Micronair AU8000 sprayer.
Some details of the procedures may differ if the sprayhead is used with a different model
of mistblower.
6.1. Output Rate of Chemical
The output rate of chemical from the sprayer will be determined by the required application
rate (in litres/hectare) and the area sprayed per minute (in hectares/minute).
The flow of chemical from the atomiser is controlled by either by the interchangeable
restrictor tube attached to the on/off valve or by an optional stepped variable restrictor
valve. The pressure of the chemical also affects the flow rate. Chemical is pressurised by
air from the blower fan so the sprayer must be calibrated with the engine running at the
maximum throttle setting.
The following steps describe the calibration procedure in detail:

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MICRONAIR AU8000 SPRAYER
1. Establish the average walking speed of the operator. This will depend upon, for
example, the target being sprayed, the evenness or slope of the ground, the amount
of chemical carried and the temperature.
The most accurate means of assessing walking speed is for the operator to spray the
actual crop or target in a 'trial run' with clean water. The speed can then be
calculated from the time to cover a measured distance.
2. Establish the width of the swath of spray on the target. In row crops or orchard
spraying this can often be determined by the number of rows sprayed at a time. In
public health or pest control spraying using a drift technique over open ground the
swath width must be determined by the use of sensitive cards or papers These
should be placed both horizontally and vertically. The cards should be mounted
downwind of the spray line. The sprayer must be used under typical conditions of
wind and temperature.
When spraying field crops or open areas (e.g. for locust control), the distance
between successive passes of the sprayer should be less than the measured
maximum swath width to ensure adequate overlap of the spray and allow for
variations in the wind and terrain.
Fig. 3 – Coverage of Sprayer

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MICRONAIR AU8000 SPRAYER
3. Calculate the area treated by the sprayer per minute. Fig. 3 shows the sprayer being
operated over a field crop.
If the operator is walking at S km/hr this corresponds to 1000 x S metres/hour:
Distance travelled = 1000 x S metres/minute
60
If the width of the swath (distance between passes) is W metres, then the area
treated per minute is:
Area treated = 1000 x S x W sq metres/minute
60
This is converted to hectares by dividing by 10,000:
Area treated = 1000 x S x W = S x W ha/minute
60 x 10,000 600
This gives the standard formula for calculating the coverage of a sprayer:
Area/min = Swath Width (m) x Speed (km/hr) ha/min
600
Example:
Speed: 4 km/Hour
Swath Width: 12 m
Therefore:
Area treated = S x W 4 x 12 = 0.08 ha/min
600 600
Table 1 shows the coverage of the sprayer for various swath widths and spraying
speeds.
4. Calculate the required output from the sprayer in litres/minute to give the correct
application rate for the chemical being used.
The output rate of chemical is given by the area sprayed (in hectares) per minute
multiplied by the required application rate in litres per hectare.
Example:
Coverage: 0.08 ha/min
Application rate: 2 litre/ha
Output = 0.08 x 2 = 0.16 litre/min
SWATH WIDTH (METRES)Speed
Km/hr 2 5 10 15 20 25 30 50
2 0.007 0.017 0.033 0.050 0.067 0.083 0.100 0.167
3 0.010 0.025 0.050 0.075 0.100 0.125 0.150 0.250
4 0.013 0.033 0.067 0.100 0.133 0.167 0.200 0.333
5 0.017 0.047 0.083 0.125 0.167 0.208 0.250 0.416
Table 1 – Coverage of Sprayer in ha/min

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MICRONAIR AU8000 SPRAYER
5. If using the interchangeable restrictor tubes, select the correct restrictor tube to give
the required flow rate. Table 2 gives the typical flow rate for each restrictor tube.
These figures are based on measurements with water. Actual flow rates will depend
upon the viscosity of the chemical being used. Note that the flow rate will also be
affected by the height of the sprayhead relative to the chemical tank. The rates in
Table 2 are measured with the tank half full and the sprayhead level with the engine.
RESTRICTOR NUMBER FLOW RATE (LITRES/MINUTE)
1 (Brown) 0.075
2 (Red) 0.150
3 (Orange) 0.300
4 (Yellow) 0.600
5 (Green) 1.200
Table 2 – Approximate Flow Rates for Restrictor Tubes
Fit the restrictor tube (8) to the outlet of the valve. Tighten the cap nut (14) firmly by
hand.
6. If using the optional stepped variable restrictor valve, rotate the knob to select the
index number corresponding to the flow closest to that calculated in step (4) above.
Note that the selector knob ‘clicks’ to each setting. The knob should not be set to a
position between the index marks. Table 3 shows the approximate flow rate for each
setting of the restrictor valve with the tank half full and the sprayhead level with the
engine.
RESTRICTOR VALVE SETTING FLOW RATE (LITRES/MINUTE)
1 0.150
2 0.250
3 0.400
4 0.550
5 0.750
Table 3 – Approximate Flow Rates with Optional Restrictor Valve
7. Push a 15 cm (6") length of 6 mm (¼") inside diameter plastic hose over the outlet of
the restrictor tube or disconnect the outlet fitting of the variable restrictor valve.
8. Ensure that the chemical on/off valve is closed.
9. Fill the tank of the mistblower to half its normal working capacity with the chemical to
be used.
10. Start the engine of the mistblower and run it at the correct operating speed (see
section 4.1).
11. Support the sprayhead at its normal operating height.
12. Place a container under the tube fitted in step (7) or the outlet of the restrictor valve
and open the chemical on/off valve until all air has been purged from the hose and
valve. Close the valve.

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MICRONAIR AU8000 SPRAYER
13. Open the chemical valve again and collect chemical for a measured time of one or
two minutes. Use a measuring cylinder or calibrated container to measure the
volume collected and calculate the output rate in litres per minute.
14. Compare the measured output rate with the calculated rate from step (4).
15. If the measured output rate is significantly higher than the required rate fit a smaller
restrictor tube or select a lower number on the restrictor valve. If it is significantly
lower fit a larger restrictor tube or select a higher number on the valve. Repeat steps
10 – 15 until the appropriate restrictor tube or valve setting is found.
16. If there is a small difference between the measured and required output rates the
track spacing and/or operator’s walking speed can be adjusted so that the calculated
rate corresponds to the measured rate. See step (3) above.
The above procedures assume that the operator can walk at a steady speed whilst
spraying. This may not be possible under some circumstances, such as when spraying
large trees. In these cases, the calibration and spraying technique should be modified as
follows:
1. Calculate the number of trees per hectare.
2. Divide the chemical application rate in litres/ha by the number of trees per hectare to
give the dose of chemical per tree.
Example:
Planting: 400 trees/ha
Application rate: 200 litre/ha
Dose = 200 = 0.5 litre/tree
400
3. Measure the time taken to spray one tree from all directions. Note that an adequate
time must be allowed for the airstream to carry spray droplets into the higher foliage.
4. Calculate the flow rate required to deliver the required dose in the measured time.
Example:
Dose: 0.5 L/tree
Time: 1.5 min/tree
Output = 0.5 = 0.33 litre/min
1.5
5. Calibrate the sprayer as described above.
6.2. Adjustment of Droplet Size
The size of the droplets produced by the sprayhead depends upon the rotational speed of
the atomiser and the properties of the chemical. The speed of the atomiser is controlled
by the velocity of air from the blower fan and by the angle of the fan blades.
As the mistblower is designed to run at a fixed blower speed, the speed of the atomiser
must be set by adjusting the angle of the fan blades.

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MICRONAIR AU8000 SPRAYER
All AU8000 sprayheads are supplied with the fan blades pre-adjusted to angle setting
number 2 (see Fig. 4). This setting should be satisfactory for the majority of applications.
If the droplet size is found to be too small, it can be increased by reducing the speed of the
atomiser by setting the fan blades to a coarser angle. Similarly, the droplet size can be
reduced by setting the fan blades to a finer angle and increasing the speed of the
atomiser.
The atomiser blade angle can be changed as follows. Numbers relate to Fig. 5.
1. Remove the screw securing the V-clamp ring (15) around the outer casing of the
sprayhead. Remove the front casing (2).
2. Remove the atomiser support ring (3) and atomiser from the rear casing whilst
pushing the feed hose through the grommet in the casing.
3. Remove the pipe clip (12) and atomiser feed hose (11). Slide the cone (5) off the
support ring.
4. Slacken the four atomiser clamp ring securing screws (118) just sufficiently to allow
the atomiser fan blades to be adjusted, see Fig. 6.
5. Adjust all four blades of the atomiser to a finer or coarser angle as required. See Fig.
4 for positions of setting marks. The blades should not be set finer than position 1 or
coarser than position 6. NOTE: For accurate alignment, the graduation mark and the
split line, view through the 10 mm hole in the atomiser support ring.
6. Tighten the clamp ring screws just sufficiently to trap the fan blades and prevent them
from moving. A torque of 0.3 nm (1 lb in) is sufficient. Overtightening the screws
could distort the hub or clamp ring.
Fig. 4 – Setting Marks on Blade

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MICRONAIR AU8000 SPRAYER
7. Reassemble the sprayhead by reversing steps (1 – 5).
8. Carry out a test by spraying the actual chemical to be used onto sensitive cards,
paper or slides. Check that the spray deposit is appropriate for the chemical and
application technique. Note that sensitive cards only give a good indication of the
number of droplets larger than about 60 microns. Smaller droplets may not mark
some types of card. The apparent size of droplets on the card will be larger than the
actual size due to spreading on the surface.
9. Note that the end cap of the gauze is provided with a conical recess in the centre.
This is intended to drive a hand-held tachometer to measure the speed of the
atomiser if required.
7. MAINTENANCE
Both the AU8000 sprayhead and the knapsack mistblower are designed for maximum
reliability and for a minimum of simple maintenance.
The following sections cover the sprayhead and general guidance for the mistblower
supplied with complete sprayers. Please refer to the Solo Port 423 maintenance manual
for full details of maintenance of the mistblower and its engine. If an alternative mistblower
is used, refer to the manufacturer’s maintenance instructions. The parts lists for the
sprayhead and atomiser are shown in section 8.
7.1. Knapsack Mistblower – Routine Maintenance
The mistblower will have a long and trouble-free life if it is kept clean and properly
adjusted. Attention must be given to the following points:
1. Chemical must NEVER be left in the tank or pipework. Always flush out the sprayer
with water or a solvent for the chemical used. Drain cleaning liquid from the sprayer
before storage.
2. Do not leave fuel in the tank or carburettor whilst the sprayer is in storage. After use,
close the fuel valve whilst the engine is running. When the engine stops, drain all
remaining fuel from the tank.
3. Check and clean the engine air filter every 50 hours (or less in dusty conditions). To
clean the filter, proceed as follows:
i) Open the filter casing by removing the securing screw and remove the foam filter.
ii) If the filter is not heavily contaminated it can be cleaned by tapping it against a
hard surface. If necessary, it can be washed in warm soapy water and then
rinsed with clean water.
iii) If the filter has been washed, allow it to dry completely and then apply a few
drops of light oil and squeeze the filter to distribute the oil.
v) Re-assemble the filter in its casing and replace the securing screw.
4. Check and clean the fuel filter. To access the filter unscrew the knurled nut securing
the fuel hose to the bottom of the fuel tank..

13
MICRONAIR AU8000 SPRAYER
5. Check the spark plug every 50 hours. If necessary, clean the spark plug and adjust
the gap setting to 0.5 mm. If the spark plug is damaged, replace with a new plug of
the correct type (Bosch W8AC or equivalent).
7.2. Possible Engine Faults and Remedies
ENGINE WILL NOT START
Fault Remedy
1. Fuel valve closed Open valve
2. Lack of fuel Add fuel
3. Hole in the fuel tank cap obstructed Open hole
4. Engine flooded See starting instructions
5. Filter below fuel tank contaminated Clean filter
6. Carburettor float valve blocked Check that float moves freelt and that
valve is not blocked. Clean as necessary
7. Spark plug contaminated with oil Clean spark plug electrodes
or carbon
8. Spark plug gap wrongly adjusted Adjust to 0.5 mm
UNSTEADY ENGINE RPM OR TENDENCY TO STOP
Fault Remedy
9. Loose spark plug Tighten spark plug
10. See points 5 - 8 above
11. Ignition lead damaged or not making Fasten or replace lead
contact
ENGINE IDLE UNSTEADY
Fault Remedy
12. Idle advance jet obstructed Clean
13. Idle advance screw requires adjustment Adjust
ENGINE DOES NOT DEVELOP MAXIMUM POWER
Fault Remedy
14. Carburettor jet contaminated Clean
15. Spark plug contaminated Clean and check gap setting (0.5 mm)
16. Choke closed. Move lever to position A(see
starting instructions)
17. Filter below fuel tank contaminated Clean filter
18. Air filter contaminated Clean

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MICRONAIR AU8000 SPRAYER
19. Exhaust hole obstructed. Remove exhaust and clean as far as
the exhaust hole in the cylinder
20. Air entering through gaskets of Tighten screws and nuts, replace
carburettor flanges, cylinder base etc gaskets if necessary
21. Wear of engine crankshaft seals Replace seals
EXCESSIVE VIBRATION
Fault Remedy
22. Broken blade on blower rotor Check rotor (this can be done by removing
the rear cushion)
23. Debris inside blower Open casing and clean
7.3. Maintenance of Sprayhead
The AU8000 sprayhead is built from chemical resistant materials and its simple design and
robust construction will ensure many years of trouble-free performance provided that it is
not mistreated and is properly cleaned after use.
The AU8000 atomiser is dynamically balanced to ensure that it will run smoothly without
vibration. Some chemicals, particularly certain ULV formulations, can dry or crystalise on
the gauze, blocking the mesh and causing the atomiser to vibrate. This can easily be
avoided by spraying 1 – 2 litres of liquid from the atomiser at the end of each spray job.
The liquid must be a solvent for the chemical which has been used. Water will normally
only dissolve water-based formulations. Kerosene or diesel fuel is suitable for most ULV
products.
The bearings of the AU8000 are sealed and are lubricated for life. The bearings should be
replaced if they become worn.
If it is necessary to replace the bearings or any other part, the procedure to dismantle the
sprayhead is as follows (see Fig. 5):
NOTE: DO NOT remove bearings unless worn.
1. Remove the inlet hose (11) from the restrictor tube on the chemical valve.
2. Loosen the handle clamping screws and slide the handle and sprayhead off the air
inlet tube (19).
3. Remove the bolt of the V clamp (15) and remove the ring from the outer casing.
4. Pull the two halves of the outer casing apart and remove the atomiser (1) and its
support ring (3). Push the feed hose through the grommet in the housing whilst
withdrawing the atomiser
5. Remove the pipe clip (12), inlet hose (11) and cone (5).
6. Remove the pipe union (7) and atomiser securing nut (112). Slide the atomiser from
the support ring.

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MICRONAIR AU8000 SPRAYER
To dismantle the atomiser, proceed as follows (see Fig. 6):
7. Remove the four screws (118) from the blade clamp ring (103), lift off the ring and
remove the blades.
8. Remove the three screws (122) securing the cap and deflector assembly (105). Pull
the cap from the end of the gauze and push the spindle (102) through the atomiser.
9. If it is necessary to remove the gauze, insert a screwdriver through the holes in the
rear of the gauze and take out the three screws (120) securing the gauze to the hub.
10. If it is necessary to remove the bearings, use a pair of circlip pliers to remove the
circlip (117) the wavy washer (121) and the sealing ring (110) from the front of the
hub. Next, push an aluminium or brass drift against the inner part of the rear bearing
and tap both bearings out through the front of the hub. Ensure that the hub (101) and
spacers (106 and 107) are not damaged or lost.
After dismantling the atomiser, the following should be checked:
Gauze (104) – Free of dents or chemical contamination
Bearings (113) – Both in good condition. If one bearing is faulty, both
must be replaced
Tolerance Rings (116) – Not cracked or deformed
Bearing Spacers – Not corroded or worn
(106 and 107)
V-Ring Seal (114) – In good condition and not cut or worn
Nilos Ring (115) – Not worn or bent
Any worn and damaged parts must be replaced with genuine Micronair spares. Any
attempt at local repair or the use of substitute parts could seriously damage the unit and
impair its performance.
The procedure to re-assemble the atomiser and sprayhead is the reverse of the
dismantling procedure. It is important that the following points are observed.
1. Fill the recess of the Nilos ring and the brass sealing (110) ring with grease. The
bearings, spacers and lip of the V-Ring should also be coated with a thin film of
grease before assembly.
NOTE: When new bearings are fitted a new Nilos ring should be fitted.
2. The bearings must be pressed squarely into the hub and must not be allowed to
become mis-aligned. They must NOT be driven in with a hammer.
3. The clamp ring (103) must be assembled in the correct position with the dimples in
the ring and hub body aligned.
NOTE: Item numbers 1 – 20 refer to Fig. 5 and item numbers 101 – 122 refer to Fig. 6.

16
MICRONAIR AU8000 SPRAYER
8. PARTS LISTS
When ordering spare parts, please specify the following information:
Serial number of sprayhead or engine
Approximate date of purchase
Description of part
Part number as shown in this section
Number of parts required
8.1. AU8000 Sprayhead
Item Part No Description Quantity
1 EX3678 AU8000 Atomiser Assy 1
2 EX3682 Front Casing Assy 1
3 EX4032 Support Ring 1
4 EX3681 Rear Casing 1
5 EX4017 Cone 1
6 EX2192 Nut 1
7 EX3673 Nipple 1
8 EX4035-39 Restrictor Tubes 1 set (5)
9 CBP1712 'O' Ring 1
10 CBP1725 Grommet 1
11 CBP1637 Tube 5 mm bore 10 mm O/D 40 cm
12 CBP1634 Pipe Clip (½") 2
13 CBP1713 Handle Assy 1
14 CBP1714 Cap Nut 2
15 CBP1628 'V' Clamp 1
16 CBP1630 Filter 1
17 EX4040 Pipe Nipple 1
18 EX2275 Bush 1
19 CBP1661 Air Inlet Tube – Straight 1
20 CBP1717 Pipe Clip (2 ¾") 2

17
MICRONAIR AU8000 SPRAYER
Fig. 5 – AU8000 Sprayhead

18
MICRONAIR AU8000 SPRAYER
8.2. AU8000 Atomiser
Item Part No Description Quantity
101 EX3666 Hub Drive Tube 1
102 EX3677 Spindle Assy 1
103 EX3669 Clamp Ring 1
104 EX3676 Gauze Assy. 1
105 EX3775 Deflector Cap Moulded type 1
106 EX3685 Inner Spacer 1
107 EX3686 Outer Spacer 1
108 EX3670 Spacer Bush 1
109 EX4404 Blade 4
110 EX5044 Sealing Ring 1
111 CBP1416 Washer 1
112 CBP1721 Stiffnut 1
113 CBP776 Bearing 2
114 CBP777 V-Ring Seal 1
115 CBP774 Nilos Ring 1
116 CBP808 Tolerance Ring 2
117 CBP2107 Circlip 1
118 CBP1720 Screw 4
119 SP127C Washer 4
120 EX2612 Bolt 3
121 EX5062 Wavy Washer 1
122 A206-C10 Screw 3