4″ Water Pump


The ES-CP41 4-inch pump by ESI pairs a Cornell Pump and Kubota diesel engine for power, performance, and durability without compromise.

The STX-Series self-priming pump by Cornell is durable, reliable, and easy to maintain with an industry leading efficiency rating. It features ductile iron construction, patented Cycloseal® sealing system, and a uniquely designed volute for best performance. Driven by a Kubota diesel engine with a maximum shaft power of 24.8hp, this 4-inch pump set delivers a 900+ gpm flow rate with 3-inch solids handling and a 90-foot max head.

The ES-CP41 is available in ESI-built skid-mounted and trailer-mounted options. Both Arctic Tough configurations include built-in 25-gallon fuel tanks.


  • Cornell STX-Series premium efficiency, self-priming pump
  • Ductile iron construction
  • Heavy-duty bearings with separate oil reserve
  • External seal leakage monitor for dual-bearing protection
  • Back pull out design for ease of maintenance
  • Self-cleaning adjustable wear plate
  • Easily replaceable suction check valve
  • Shimless impeller


  • Kubota V1505 or V1703 (ES-CP40), variable speed diesel engine
  • DSE control panel for ease of operation and engine speed monitoring
  • Racor fuel and water separator


  • Rugged, Arctic Tough designs by ESI
  • 25-gallon built-in fuel tank


PumpCornell 4STX-EM4
Suction4″ 125# flangeASTM A536 Grade 65-45-12 ductile iron suction
Discharge4″ 125# flange
Max flow900 gpm
Max head (lift)90′ (27.4 m)
Max solids size3″ (76mm)
Max speed2100 rpm
ImpellerSemi-open design, 2 vane3″ Spherical solids handling capabilityASTM A536 Grade 100-70-03 ductile iron
Pump and drive end bearingsRadial bearing single-row ball and thrust bearing double-row ball
Bearing house materialASTM A48 Class 30/35 gray iron
Shaft material1144 Stress-proof steel chromed and gray iron
Volute casingASTM A536 Grade 65-45-12 ductile ironTangential discharge with cleanoutClockwise rotation (viewed from driven end)
Mechanical sealSingle-type sealTungsten carbide vs. silicon carbide seal facesViton elastomers300 Series stainless steel hardware and spring
EngineKubota V1505 or D1703 (ES-CP40), variable speed
Max shaft power24.8 hp
Fuel typeULSD
Fuel capacity25 gal
Fuel consumption1.3 gph @ 2000 rpm
Skid-mounted weightDry: 1523 lb (691 kg)
Wet: 1722 lb (781 kg)
Trailer-mounted weightDry: 1743 lb (791 kg)
Wet: 1941 lb (880 kg)

Model #






Highlight Specs

Engine HP: 35hp
Max GPM: 900
Max Head (ft): 90
Max Solids Handling: 3"
Priming System: Self-Priming
Configuration: Skid or Trailer