3
20
21
1
19
2
3
4
5
7
6
18
16
13
12
17
8*
14
15
16
10
11
12
13
9
Components List
Item No. Part Description
Quantity
1
Engine – 3.5 HP
1
Engine – 5.5 HP
2
Locknut –
3
⁄
8
" – 16
4
3
Engine adapter
1
4
Aluminum washer –
5
⁄
16
" 4
5
Bolt –
5
⁄
16
" – 24" x
3
⁄
4
" 4
Seal assembly
6
Shaft sleeve
1
O-ring housing
O-ring volute
Impeller
1
7 Volute
Impeller shim: 010, 020, 030
3
Hose mounting gasket
2
8*
Hose mounting nipple
2
Hose mounting nut
2
Suction strainer
1
9
Suction strainer
1
13
Pump housing
1
14
Bolt –
3
⁄
8
" – 16" x 1
1
⁄
2
" 4
15
O-ring, drain/filler plug
2
16
Drain/fill plug
2
17
Flapper valve
1
18
Suction flange BSP*
1
Suction flange NPT
19
Bolt –
5
⁄
16
" – 18" x
7
⁄
8
" 7
24
Discharge elbow BSP*
1
Discharge elbow NPT
25
Discharge gasket
1
26
Bolt –
5
⁄
16
" – 18" x 1
1
⁄
2
" 4
27
Lock nut –
5
⁄
16
" – 18
4
28
Cradle assembly
1
* Supplied with 2AU, built before September 2005.
See RAU – Model AU Repair Part bulletin for part order numbers.
2.6 Place the pump on level, firm foundation, putting it
as near as possible to the level of the liquid which is
to be pumped, but never higher than 25 feet (7.5 me-
ters). Keep all lines straight and as short as possible.
Avoid sharp bends.
3. Operating Instructions
3.1 STARTING – See Engine Manual
3.2 PRIMING TIME – with a suction lift from 5 to 10
feet (1.5 to 3 meters)*, the pump should discharge
liquid in less than a minute; a suction lift of 25
feet (7.6 meters)*, requires less than 2 minutes. To
further reduce priming time the engine speed may
be increased, after the engine is properly broken in.
If pumping does not start within this time, shut off
engine and check to find the difficulty (see Trouble-
shooting).
3.3 CONTROL – On high suction lifts, a higher engine
speed is necessary. On shallow lifts or when there is
but a little liquid to pump, save fuel and engine life
by reducing the engine speed. (See Engine Manual)
3.4 CHECK VALVE – If discharge line runs vertically
more than 30 feet (9 meters), it is advisable to install
a check valve in the discharge line near the pump to
stop destructive water hammer when pump is shut
down. If this is done, it may be necessary to vent the
top of the pump so that air can be expelled during
automatic re-priming. This air bleed may be accom-
plished by providing a ¼" (.5 cm) line from the top
of the pump back to the liquid source. We will not
assume any responsibility for damage to the pump if
no check valve is used in the discharge line. Properly
fueled and lubricated, your pump will run without
attention.
3.5 If flexible hose must be laid across a roadway, protect
it with planking. Instantaneous shutoff pressure ap-
plied when a vehicle runs over an unprotected hose
will cause “hydraulic shock”, which may damage the
casing or seals.
3.6 Drain the pump body whenever there is danger of
freezing.
3.7 Always flush out the pump at the end of operation if
the liquid being pumped may leave a solid or sticky
residue in the pump. If this is not done, damage to
the pump may result.