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Flojet 4000 Series 12V Demand Pump – R4300-504A (Replaced by Q451F-168S-2P)
The Flojet 4000 Series Demand Pump – 12V (R4300-504A) was a high-capacity diaphragm pump widely used for spraying, liquid transfer, circulation, and dispensing. With a maximum flow rate of 19.5 L/min and a 3.1 Bar switch setting, it was a popular choice for agricultural and industrial applications.
⚠️ Important Notice: As of July 2025, this model has been discontinued. Flojet has replaced the 4000 (Quad) Series with the modern Versijet 4-Chamber Series, designed as a direct replacement with the same footprint and port sizes for hassle-free installation.
The Flojet Versijet Q451F-168S-2P is the upgraded replacement for the discontinued R4300-504A. Featuring a 4-chamber diaphragm, this pump provides smoother operation, longer life, and improved reliability. With Quick Connect 3/4" hose barb ports and the same mounting footprint, it can be installed as a direct swap.
The Versijet Series is Flojet’s new generation of industrial pumps, delivering:
Direct-fit replacement for 4000 Series models (same footprint and ports)
Higher efficiency and smoother operation
Stronger construction for extended service life
Quieter performance compared to legacy models
Replace your discontinued Flojet 4000 Series R4300-504A with the new Flojet Versijet Q451F-168S-2P.
3.1 Bar switch setting
19.5 Lpm max flow
12 Volt DC, 13.0 Amps
Santoprene diaphragm
Viton check valve
3/4" hose barb ports
Self-priming, up to 2.4m
54°C max fluid temperature
Integrated pressure/demand switch
Fitted with thermal overload
Polypropylene pump housing
FLJ 4000 PARTS LIST.pdf
FLJ 4000 SERIES TECH DATA.pdf
FLJ 4100 SERIES USER MANUAL.pdf
FLJ 4300 SERIES USER MANUAL.pdf