6.3.4 Maintenance and repair

Manual knapsack sprayers are typically maintained by farmers themselves, although there have been Government or cooperative support initiatives. 

It can be difficult to convince smallholders that it usually pays in the long-term to choose a good quality, robust sprayer, as they will always ask the question “Will I be able to find spare parts for it?”. 

A few basic extension messages:

Before spraying the farmer should check:

• Is the sprayer working properly? 
  Before each spray operation, check equipment using clean water only
• Are there any faults or blockages? Check pump, valves, filters and nozzle.
• Are there any leakages? 
  If spare parts are not available, joints can be repaired with white (plumber’s PTFE) tape or rubber seals (can be made out of old tyre inner tubes). Replace worn and leaking hoses. 

Leaking sprayers are a problem because of: 
 

• operator exposure to tank mixture
• incorrect application rates [1]
• increased soil contamination