Great Plains NP4000 40-foot Operator Manual - Manual (Page 80)

76 NP4000 Table of Contents Index Great Plains Manufacturing, Inc.
407-776M Table of Contents Index 2012-03-28
Ground Drive Pump Troubleshooting
The CDS-John Blue NGP Pump Parts and Instructional
manual (12-M-43) has additional troubleshooting
information.
Problem Cause Solution
Low Rate Ground drive on Low Range when
rate requires High Exchange Range sprockets (page 72).
Dial setting incorrect Re-check Range and Dial settings for rate.
Ground drive slipping Check condition of arm and chains. Check operating height
of implement (may be too high). If soil is too wet, try
reconfiguring for a lower manifold pressure, or wait for dryer
conditions.
Pump damaged See CDS-John Blue NGP Pump Parts and Instructional
manual.
High Rate Ground drive on High Range when
rate requires Low Exchange Range sprockets (page 72).
Dial setting incorrect Re-check Range and Dial settings for rate.
Low Manifold
Pressure Relief valve set too low Adjust relief valve (page 71).
Ground drive on Low Range when
rate requires High Exchange Range sprockets (page 72).
Field speed too low Increase speed or reduce orifice plate size.
Ground drive wheel or chains
slipping Check condition of arm and chains. Check operating height
of implement (may be too high). If soil is too wet, try
reconfiguring for a lower manifold pressure, or wait for dryer
conditions.
Product
Dumping at
Relief Valve Rate, speed or material viscosity too
high for orifice plate size Re-check pump rate determination, Range sprocket, pump
dial and console setup (Option). If correct, replace orifice
plates with a larger size (page 69).
Orifice plates clogged Use larger plates (page 69) or finer strainer screen
(page 71).
Relief valve set too low Adjust relief valve (page 71).
Applicators plugged Clean out applicator tubes
Material slushy due to low
temperature, or actual ice in boom Wait for warmer conditions.
High Manifold
Pressure Ground drive on High Range when
rate requires Low Exchange Range sprockets (page 72).
Field speed too high Reduce speed or increase orifice plate size.