Control Valves; System Dynamics - Cushman Spraytek DS175 Safety & Operation Manual

6 SPRAYER OPERATION
6.2

CONTROL VALVES ________________________________________________________

The control valves for determining which accessory to
use are located on the left side of the vehicle directly
behind the operators seat.
The agitator control handle controls an eight jet nozzle
assembly in the lower tank sump area. This handle
controls the amount of liquid passing through the nozzles
allowing complete agitation for mixing loaded chemicals
with carrier (water). It is recommended to leave this valve
fully open at all times even with low tank liquid level.
The hose reel and boom valve allows isolated use of
either the hose reel or the boom. The hose reel position
allows hook-up to a hand-held spray gun or walking type
spray boom. The boom position allows use of all spray
boom accessories.
The boom control valve needs to be open if the hose reel
and boom selector valve is in the boom position, if the
selector valve is in the hose reel position, this control
valve needs to be in the closed position.
The suction valve needs to be in the open position for
normal operation. If the pump and/or the filter need
servicing or repair, this valve can be turned to the closed
position (with liquid in the tank) allowing these items to be
worked on.
6.3

SYSTEM DYNAMICS _______________________________________________________

The sprayer pump is belt driven off the engine. Electrical
power for the sprayer is supplied by the vehicle battery.
The sprayer to truck mounting style makes the two
systems act as one complete machine.
!
WARNING
DO NOT operate sprayer pump with out liquid present in
the system. Mechanical seals must be constantly
lubricated with cool circulating liquid (spray mix).
Running the system dry will heat up the ceramic seat and
the addition of a cool liquid to a hot/dry seal will cause
the ceramic to crack.
Centrifugal Pump Lubrication - lubrication for the
impeller inside the pump housing (volute) is your spray
liquid. This liquid lubricates the mechanical seal (made of
ceramic and graphite rings) that are around the impeller
shaft. The pump rotation creates heat, so the liquid is
also needed for cooling.
24
Agitator Control
The centrifugal pump is lubricated by the spray material
therefore, the use of certain materials may affect
maintenance or operation techniques.
Venturi-Jet Agitator Nozzles - installed with ceramic
metered orifices (ceramic is a longer lasting material in
comparison to plastic). Long lasting ceramic orifices
provide stable agitation flow rates for trouble-free fluid
mixing.
Suction Strainer - provides liquid filtering of particulate
matter in spray material. Screen mesh sizes available
are: 20, 50, 80 and 40 (standard) in SST material. The
suction strainer (filter) should be cleaned daily or more
often as the need arises. Remember to close the suction
ball-valve (if liquid is in the tank) before removing the
strainer.
Non-Corrosive Plumbing - all sprayer plumbing is SST,
nylon or PVC, or polypropylene for all liquid handling
parts.
Handle
Hose Reel and Boom
Selector Valve
Figure 6A
Boom Control
Valve
Suction Valve
Figure 6B