Pressure Washer Pump 3700 PSI 2.5 GPM, 19 mm Shaft

Pressure washer replacement pump restores strong, consistent cleaning power without replacing your whole unit. Built for gas pressure washers with horizontal engines, it uses a standard SAE bolt pattern and a 3/4" (19 mm) shaft to simplify swaps. The triplex plunger design targets wear and seal life, while a forged brass, one-piece head supports reliable sealing under high pressure. A built-in sight glass makes oil checks fast and clear.

• Delivers up to 3700 PSI and 2.5 GPM to bring back effective spray performance


• Fits many horizontal-shaft gas pressure washers with a standard SAE bolt pattern


• Resists wear with hardened plungers to help reduce damage from debris and impurities


• Improves sealing with a one-piece forged brass pump head for strength and durability


• Enables quick maintenance via an oil sight glass to spot low or cloudy oil at a glance

Use it for outdoor walls, sidewalks, vehicles, and jobsite cleanup—anywhere you need steady pressure and flow. Before ordering, confirm your washer’s engine orientation, PSI/GPM requirements, shaft diameter, and inlet/outlet connection style to ensure a proper match. This replacement pump kit is designed to be a practical repair that keeps your existing washer working and reduces downtime. Grab yours today and get your pressure washer back in service.

• Max pressure: 3700 PSI


• Max flow: 2.5 GPM


• Shaft diameter: 3/4" (19.05 mm)


• Engine compatibility: horizontal shaft; 5.5–8 HP range


• Size (L x W x H): 9.62" x 7.7" x 6.22" (24.45 x 19.58 x 15.8 cm)


• Weight: 12.1 lb (5.5 kg)