Valeport BFM001, Operating Manual, Page: 6 / 32

Model 001 & 002 Flowmeter Operating Manual
MANUAL-1550859975-1 | issue: 1.1
©
2021
– Valeport Ltd
Page | 3
3 Maintenance Instructions
The BFM001 and 002 flowmeters have been designed to require minimum maintenance under
normal operating conditions. The Control Unit and wading/suspension cables should require no
maintenance other than routine inspection and cleaning. It is recommended that the flowmeter
itself is thoroughly washed and cleaned in fresh water after each deployment. If the unit has been
used in silt
‑
laden water, the impeller should be removed and the impeller bearings and shaft also
washed in clean water. This will significantly extend the life of the impeller and shaft.
On no account should a sharp instrument be used in the cleaning process. For extreme
conditions, particularly where there are metallic particles in suspension, impellers with extended
skirts are available. Before repacking into the carrying cases, all items should be completely dried
to prevent any tarnishing of the equipment whilst in transit or storage. Instructions are detailed
below for routine maintenance procedures:
3.1 To replace an Impeller
Refer to Figure 1 (BFM001) and Figure 3 (BFM002) .
3.1.1 To remove Impeller
i.
Unscrew the nose cone of the impeller anticlockwise to remove.
ii.
With a 3mm spanner, hold the nut nearest to the washer, and with another spanner release the
other nut.
iii.
Remove both nuts, washer and impeller.
iv.
Clean the hub face and the impeller shaft to remove any silt or dirt.
v.
Check the wear condition of the shaft to ensure the bearing areas are clean and smooth.
If there is significant wear on the shaft, it should be replaced.
3.1.2 To replace Impeller
i.
Stand the meter down on its end face with the shaft pointing upwards, and replace impeller with
the nose cone fitted.
ii.
Unscrew the nose cone to allow the impeller to rest against the main body hub face.
iii.
Hold the impeller down against the hub face and slowly screw down the nose cone until it
begins to lift the impeller away from the hub face.
iv.
Check that the clearance between the nose cone and the impeller end face is within tolerance
(0.5 to 0.75 mm, 0.02 to 0.03 in). If the distance is outside this range, then the shaft will need to
be adjusted.
v.
Remove the nose cone and fit the washer and nuts supplied, setting the gap between the
washer and front hub of the impeller to 1.5 mm (0.062 in).
vi.
Replace nose cone, checking gap as in item iv. Finger tight only is sufficient; undue force may
cause damage.
At no time should any lubricant be applied to the shaft or bearings. The only lubrication needed
is given by the water the unit is used in.