TOOLCY 4400 PSI Pressure Washer Pump — 1" Shaft Horizontal Triplex, Brass Head & Adjustable Pressure

TOOLCY 4400 PSI Pressure Washer Pump is a horizontal triplex plunger replacement pump with a 1" shaft, adjustable pressure up to 4400 PSI and durable brass head for gas power washers.

This heavy-duty replacement pump is built for use with 10–15 HP (270–420cc) gas engines and fits common models such as Honda GX340/GX390 and many Simpson, AR and CAT units. Designed as an OEM-quality swap, it brings a fully anodized crankcase, brass pump head, stainless quick-connect outlet, and a red pressure adjustment knob. The triplex plunger arrangement reduces pulsation and improves longevity compared with cheaper pumps.

Will this pump fit my pressure washer engine?

Compatibility rests on a few measurable details: engine shaft diameter, engine orientation (horizontal), flange mounting pattern, and the inlet/outlet thread sizes. The TOOLCY pump uses a 1" shaft hole, standard SAE flange dimensions, a 3/4" garden-hose inlet and a 3/8" stainless quick-connect high-pressure outlet.

• 1" shaft hole for horizontal-mounted engines
• Standard SAE flange mounting dimensions
• 3/4" garden hose inlet and 3/8" QC high-pressure outlet
• Compatible with many GX270/340/390 and Simpson/AR/CAT models listed

How do I adjust pressure and what operating range is recommended?

A visible red knob on the pump lets you increase or decrease outlet pressure without extra tools. While the pump is rated to a maximum of 4400 PSI and 4.4 GPM, TOOLCY recommends operating around 3400 PSI at 3400 RPM for balanced performance and longer service life.

• Red adjustment knob for quick pressure tuning
• Maximum spec: 4400 PSI / 4.4 GPM
• Recommended working pressure: ~3400 PSI at 3400 RPM
• Suitable for residential and light-commercial cleaning tasks

What construction and materials improve durability?

The pump pairs a fully anodized aluminum crankcase with a solid brass pump head and stainless steel outlet for corrosion resistance and mechanical strength. Triplex plungers reduce vibration and improve smoothness; modern sight glass and oil-seal design remove the need for a dipstick while simplifying maintenance checks.

• Anodized crankcase to resist wear and corrosion
• Brass pump head for strength and heat resistance
• 3/8" stainless steel quick-connect outlet for longevity
• Sight glass and oil seals for easy oil-level monitoring

What accessories and packaging are included?

The pump ships with five pressure washers nozzles and an adapter plug (3/8" QC to M22-14mm male) so you can connect common high-pressure hoses and spray tips right away. Typical hardware for mounting and detailed instructions may vary; verify what comes in your specific listing before installation.

• Five pressure washer nozzles for varied spray patterns
• 3/8" QC plug to M22-14mm male adapter included
• Standard pump flange compatible with SAE mounting patterns

Who is this for: This TOOLCY pump is aimed at DIY mechanics, landscapers, and small contracting businesses that need a robust replacement pump for horizontal-shaft gas pressure washers (10–15 HP / 270–420cc). Choose it if your current pump shows wear, if you need adjustable output for multiple cleaning jobs, or if you want an OEM-quality upgrade with brass components and stainless fittings. Before purchasing, confirm shaft diameter, engine orientation, PSI/GPM needs, and inlet/outlet connections to ensure a correct fit.