High Pressure Plunger Pump · Frame size 4SP

4SP21EL

Name: 4SP21EL
Brand: CAT PUMPS
SKU: 4SP21EL

This triplex (three plunger rods) positive displacement, reciprocating plunger pump is constructed with a brass manifold, 304 stainless steel valve assemblies, solid ceramic plungers and standard NBR (Buna-N) seals and O-rings. This pump model does not include a pressure control device, opening possibilities for multiple plumbing configurations.

Data sheet (PDF) Make an enquiry

Technical specifications

Flow rate	7.9 l/min
Operating pressure	138 bar
Speed	1,750 min⁻¹
Inlet port	3/8" NPT(F)
Discharge port	3/8" NPT(F)
Shaft diameter	5/8" (hollow shaft)
Material	Brass

Downloads

CAD files

STEP – 4SP21EL (catpumps.com)

Spare parts

Click an item in the drawing or in the parts list to add it to your request list. We turn it into a quotation – no order is placed.

2 kits bundle wearing parts of this pump ↓

Parts list

Item	Part no.	Description	Qty
5	549360	Screw, HH (M6 x 14)STCP	3
8	547153	Cover, BearingAL	1
10	14041	O-Ring, Bearing Cover - 70DNBR	1
11	55337	Seal, Oil, CrankshaftNBR	1
15	14488	Bearing, Ball, InnerSTL	1
20	547020	Assembly Rod, ConnectingTNM	3
25	132605	Crankshaft, 5/8", (8.1 mm) (Models 4SP21ELR, ELU)CM	1
26	12385	Ring, Retaining, BearingSTL	1
27	15710	Bearing, Ball, OuterSTL	1
32	549726	Cap, Vented with O-Ring (Rain Cap)	1
33	14179	O-Ring, Oil Filler Cap - 70DNBR	1
37	92241	Gauge, Oil, Bubble with Gasket - 80D 1 - 2PC	1
38	44428	Gasket, Flat, Oil Gauge - 80DNBR	1
48	44842	Plug, DrainNY	1
49	14179	O-Ring, Oil Filler Cap - 70DNBR	1
53	547099	CrankcaseAL	1
64	16948	Pin, CrossheadCM	3
65	49982	Rod, PlungerBB	3
69	126259	Washer, Oil SealSTCP	3
70	25301	Seal, Oil - 80DNBR	3
88	132607	WasherS	3
90	132606	Plunger (M16 x 24.6) (Models 4SP21ELR, ELU)CC	3
98	46730	Washer, Seal - 90DNBR	3
99	542405	Retainer, Plunger (M6 x 35)S	3
100	44869	Retainer, SealPVDF	3
106	48222	Seal, Low-Pressure with S-SpringNBR	3
120	132608	Case, Seal (Models 4SP21ELR, ELU)BB	3
121	13977	O-Ring, Seal Case - 70D (Models 4SP21ELR, ELU)NBR	3
125	547157	Seal, High-Pressure (Models 4SP21ELR, ELU)SNG	3
160	17428	O-Ring, Inlet Seat - 80DNBR	3
161	547077	Seat, InletS	3
162	48361	Backup Ring, SeatD	3
163	670085	O-Ring, Discharge Seat - 90DNBR	3
164	547076	Seat, DischargeS	3
166	547098	ValveS	6
167	134579	SpringS	6
168	543988	Retainer, Spring, InletPVDF	3
169	49764	Retainer, Spring, DischargePVDF	3
172	142807	O-Ring, Valve Plug - 90DNBR	3
174	547104	Plug, Valve (M20 x 1.5) with O-RingBB	3
185	132609	Head, ManifoldFBB	1
188	549357	Screw, HSH (M6 x 60)STCP	8
197	941516	Assembly, Garden Hose (3 /8" NPT[M] x 3/4" GH[F])BB	1
255	30516	Assembly, Bolt MountSTZP	1
–	6132	Oil, Crankcase, Bottle 1l	1

in the request listcovered by a requested kit

Seal and valve kits

A kit bundles the wearing parts of one assembly. Selecting it highlights the items it covers in the drawing and the parts list – once requested, they stay marked.

Seal kits

Seal kit
76968
NBRMedium Nitrile (Buna-N)
contains 4 items · one kit per pump
Parts list
- 9846730Washer, Seal - 90D3×
- 10648222Seal, Low-Pressure with S-Spring3×
- 12113977O-Ring, Seal Case - 70D (Models 4SP21ELR, ELU)3×
- 125547157Seal, High-Pressure (Models 4SP21ELR, ELU)3×

Valve kits

Valve kit
76976
NBRMedium Nitrile (Buna-N)
contains 10 items · one kit per pump
Parts list
- 16017428O-Ring, Inlet Seat - 80D3×
- 161547077Seat, Inlet3×
- 16248361Backup Ring, Seat3×
- 163670085O-Ring, Discharge Seat - 90D3×
- 164547076Seat, Discharge3×
- 166547098Valve6×
- 167134579Spring6×
- 168543988Retainer, Spring, Inlet3×
- 16949764Retainer, Spring, Discharge3×
- 172142807O-Ring, Valve Plug - 90D3×