21
Pump Maintenance
The pump diaphragms are wearing
components that need to be replaced during
the life of the pump. Life expectancy depends
upon pump operation and maintenance and
task suitability.
MAINTENANCE GUIDELINES
• Pump diaphragms should be replaced
prior to diaphragm failure.
• Where the sprayer is used extensively,
the pump should be reconditioned once a
season, including replacing diaphragms,
seals and valve springs.
• It is recommended to keep a spare pump
repair kit (including diaphragms, seals,
valve o-rings and springs) on hand in case
of a breakdown.
• A change of oil colour indicates a pump
problem. The oil should be regularly
monitored when spraying so that any
problem is detected as soon as possible.
If the oil goes milky in colour, it is likely the
diaphragm has split and the spray mixture
has come into contact with the oil. If the
oil goes black (or dark grey), it is likely the
pump has overheated.
MAIN CAUSES OF PREMATURE
DIAPHRAGM FAILURE
• Blocked or incorrectly fitted suction filter
restricting flow to the pump.
• Incorrect air damper chamber pressure.
• Running pump at speeds greater than 600
RPM.
• Exceeding the 290 PSI pressure limit of
the pump.
• Failure to wash chemicals from pump after
use.
• Incompatibility of the diaphragm material
and the chemicals used.
DIAPHRAGM REPLACEMENT
When diaphragms require replacement it is
normal practice to replace the air damper
diaphragm at the same time.
1. Flush pump with clean water to remove
chemical residue, then flush with
appropriate decontaminating agent (refer
to chemical label for decontamination
instructions).
2. Run pump dry for 15-20 seconds to
remove water.
3. Remove all air from air damper chamber
by pushing in air valve.
4. Remove pump from sprayer.
5. Remove pump manifolds and pump
heads.
NOTE:
Carefully note the position and
orientation of all heads, manifolds and
valves when disassembling pump. Failure to
reassemble correctly will result in severe pump
damage.
6. Drain oil from pump.
7. Remove diaphragms.
8. Remove cylinder sleeves.
9. Flush inside of pump with diesel.
10. Visually inspect inner workings of pump.
11. Reassemble with correct new diaphragms
only once satisfied with condition of pump.
12. Refill with SAE 15W40 oil. Rotate pump by
hand to remove air locks. Do not overfill.
