Great Plains CDS-JohnBlue NGP Series Pumps - Manual (Page 13)

© 2013 CDS-John Blue Co. 13
INTERNAL DISASSEMBLY
Reference to the schematic section is recommended prior to disassembly of the internal crankcase components
to familiarize yourself with components. The wet-end components, inboard, and outboard components should
be removed prior to internal disassembly as outlined in previous sections of this manual.
 Supporting the piston rod with a wood block, locate the
crosshead pin, which connects the piston rod and connecting
rod and carefully drive pin out with a hammer and punch.
 Inspect the connecting rod bushing for damage and replace as
necessary during re-assembly.
 Slide the outer eccentric and eccentric pin out of the crankcase.
 The connecting rod can then be removed by carefully sliding it
out the side of the pump at an angle.
 The shaft can then be removed as shown with the inner
eccentric still in place.
Note: Double piston pumps will require the stroke transfer
sleeve to be removed with the shaft exposing the
second piston eccentric and connecting rod for removal.
 The stroke setting sleeve is then removed.
 The eccentric pins may slide out during any
part of this process and should be
accounted for, single pumps utilize 1,
double pumps utilize 3 [ref schematic].
 Examine all components, giving more
attention to ones showing “galling” than to
ones which are undersize, yet smooth.
CRANKCASE RE-ASSEMBLY
 All components in the gasket kit should be used during re-assembly.
 Reassemble the crankcase in reverse order.
 When assembling the shaft, oil the shaft o-ring and carefully insert into stroke setting sleeve.
 It is extremely important that all eccentric pins engage appropriate mating slots.
 Coat all bolts threads with gasket sealant before installing in crankcase.